Pianotech

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

I have researched rib scales for decades as you know. I have analyzed scales of roughly a thousand soundboards. I even have a couple of your scales, LOL So i can confidently say your approach is wrong and your premise is flawed. One can only conclude that you are unsatisfied with the results you have obtained up until now, and wanting to improve your craft, but the idea of  getting a "more balanced sound" by minutely changing rib scales will be fruitless i'm afraid. 

Another flaw is to ask others for their rib scales. Every rib scale i have that i hold of high value, are boards that i listened to before and after i rebuilt them. So when you get a rib scale from others you wont have that necessary input to go with it. So just going by numbers is meaningless. See what i mean? And that is just one example.

-chris

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

Last time you "weighed in" you claimed to have reduced mass by 6 lbs in an average board. Still waiting for you to disclose exactly where that weight comes from. I've asked several times with no response. Six lbs is about the weight of half the ribs in the board btw.  I have my doubts about such claims. 

Your other comments I won't dignify by responding to except to say it's not very in keeping with expected behavior on this list. Nor are your advertisements contained in your signature, btw. You might double check the rules of engagement here before someone else does. 

I too have been collecting data and analyzing soundboards for decades though not without input and discussion from other techs and engineers over these many years. I try and get out of my own bubble once in awhile.  My interest remains and I hope others who may wish to participate are not discouraged by your specious and antagonistic claims. 

The purpose of this is to see how uniform executions are between similar sized pianos with similar string scales, if not the exact same model. Why I'm doing it this way I'd be happy to explain to anyone interested.

The rib scale remains an essential component of the design and one in which we see some variation even when the panel treatment is the same. Rib scales are not the only design element of course, but it is an essential one and one that gets modified routinely for different reasons. 

I have researched rib scales for decades as you know. I have analyzed scales of roughly a thousand soundboards. I even have a couple of your scales, LOL So i can confidently say your approach is wrong and your premise is flawed. One can only conclude that you are unsatisfied with the results you have obtained up until now, and wanting to improve your craft, but the idea of  getting a "more balanced sound" by minutely changing rib scales will be fruitless i'm afraid. 

Another flaw is to ask others for their rib scales. Every rib scale i have that i hold of high value, are boards that i listened to before and after i rebuilt them. So when you get a rib scale from others you wont have that necessary input to go with it. So just going by numbers is meaningless. See what i mean? And that is just one example.

-chris

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

This is a sad recurring comedy. Like Groundhog Day in reverse.  Because i got tired of repeatedly answering your questions without you comprehending the answer, i made a video for you FOUR YEARS AGO on this very topic.

https://youtu.be/IQ5vcmJWfkQ?si=dhGHCkfCaSOp3ZN3

Last time you "weighed in" you claimed to have reduced mass by 6 lbs in an average board. Still waiting for you to disclose exactly where that weight comes from. I've asked several times with no response. Six lbs is about the weight of half the ribs in the board btw.  I have my doubts about such claims. 

Your other comments I won't dignify by responding to except to say it's not very in keeping with expected behavior on this list. Nor are your advertisements contained in your signature, btw. You might double check the rules of engagement here before someone else does. 

I too have been collecting data and analyzing soundboards for decades though not without input and discussion from other techs and engineers over these many years. I try and get out of my own bubble once in awhile.  My interest remains and I hope others who may wish to participate are not discouraged by your specious and antagonistic claims. 

The purpose of this is to see how uniform executions are between similar sized pianos with similar string scales, if not the exact same model. Why I'm doing it this way I'd be happy to explain to anyone interested.

The rib scale remains an essential component of the design and one in which we see some variation even when the panel treatment is the same. Rib scales are not the only design element of course, but it is an essential one and one that gets modified routinely for different reasons. 

I have researched rib scales for decades as you know. I have analyzed scales of roughly a thousand soundboards. I even have a couple of your scales, LOL So i can confidently say your approach is wrong and your premise is flawed. One can only conclude that you are unsatisfied with the results you have obtained up until now, and wanting to improve your craft, but the idea of  getting a "more balanced sound" by minutely changing rib scales will be fruitless i'm afraid. 

Another flaw is to ask others for their rib scales. Every rib scale i have that i hold of high value, are boards that i listened to before and after i rebuilt them. So when you get a rib scale from others you wont have that necessary input to go with it. So just going by numbers is meaningless. See what i mean? And that is just one example.

-chris

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

Oh, I saw that.  Not the most productive 4 minutes of my life.  You don't answer the question btw, you simply say this is "the reason not to copy".  I agree with that, btw, the rib scale research I'm doing is for that very purpose, the reason not to copy, or to be cautious anyway.  But I'm showing one way to apply some type of structural analysis not just start carving off weight for its own sake.  The analysis I'm showing is a proven and legitimate method of analysis and some form of that is used by many very established people in this industry that everyone would recognize, though I will spare them the mentioning of their names given the tenor of this "dialogue".    

In the original discussion we were having, you claimed to remove up to 6 lbs of material and that was in the context of Steinway soundboards which are somewhat uniform in rib scale executions and soundboard thickness (typically about 9 mm).  When you are talking about removing up to 6 lbs of material that's 1/3 of the weight of the heaviest board you showed (18lbs) and 40% of the lighter one (15 lbs).  You still didn't, and haven't, answered the question of where the material comes from. 

In your video, you suggest, among other things, that it might be partly the finish because, hey, "pick up a can of finish, it's heavy".  Well, a can of finish is largely solvent (typically around 75%) and a fraction of a can is used in the finishing of a soundboard.  So by the time the finish dries, it's lost 75% of its weight.  Inconvenient.  So, let's be generous.  When you calculate the thickness of the finish to determine volume and then go through the machinations to figure out the actual weight of that dried finish you come up with something like, I'll be generous, maybe .25 lbs for both sides and since soundboard finishes tend to be pretty thin I doubt it even comes near that.  That's a mid sized board.

So then, where does the other 5.75 lbs come from?  A 5' length of 1" x 1" rib stock weighs about .6 lbs (I was overly generous in my previous off the cuff estimate).  So that means, if each rib was 1" x 1" (which they aren't) and 5' long (which they aren't) you'd be removing 10 complete ribs from the assembly!!!  How's that workin' for ya?     

So then, what about the soundboard panel.  Well let's say on your 18 lb board the scalloped ribs weigh 2 lbs (that's generous) and you reduce the rib widths by 1/4 so as not to compromise stiffness too much (height counts more than width for stiffness). You've saved ~.5 lbs.  That still leaves a panel that weighs 17.5 lbs and we have 5.5 lbs to go.  So, if the panel is 9 mm thick (pretty typical) then you would have to thin the panel down by 5.5/17.5 of its total thickness.  That means reducing that 9 mm panel to about 6 mm in overall thickness and possibly more in the center if the perimeter is diaphragmized already.  That's not something I would do, or recommend.  

So, you still haven't adequately answered the question, or maybe you have, in which case I'd say, kids, don't try this at home.  

I do agree with an implied principle, which you haven't really stated, but as a guiding principle--and which still requires the application of numbers.  That is: light but not too light, stiff but not too stiff.  We might have something in common there, but I'm not holding out hope.

But I'm not really posting this to argue soundboard building philosophy.  If you want to reduce your boards by 6 lbs, have at it.  I'm doing comparative research on rib scales.  So, I would appreciate it if you could exercise the tiniest bit of class, stop being antagonistic and take your commentary to FB or X where I'm sure you'll find a welcome home and spare me the indignity of reporting your posts as lacking in professional conduct.  IOW, stop harassing me.

Those who wish to participate in my data collection you are welcome to share data privately.  I wouldn't blame you. 

This is a sad recurring comedy. Like Groundhog Day in reverse.  Because i got tired of repeatedly answering your questions without you comprehending the answer, i made a video for you FOUR YEARS AGO on this very topic.

https://youtu.be/IQ5vcmJWfkQ?si=dhGHCkfCaSOp3ZN3

Last time you "weighed in" you claimed to have reduced mass by 6 lbs in an average board. Still waiting for you to disclose exactly where that weight comes from. I've asked several times with no response. Six lbs is about the weight of half the ribs in the board btw.  I have my doubts about such claims. 

Your other comments I won't dignify by responding to except to say it's not very in keeping with expected behavior on this list. Nor are your advertisements contained in your signature, btw. You might double check the rules of engagement here before someone else does. 

I too have been collecting data and analyzing soundboards for decades though not without input and discussion from other techs and engineers over these many years. I try and get out of my own bubble once in awhile.  My interest remains and I hope others who may wish to participate are not discouraged by your specious and antagonistic claims. 

The purpose of this is to see how uniform executions are between similar sized pianos with similar string scales, if not the exact same model. Why I'm doing it this way I'd be happy to explain to anyone interested.

The rib scale remains an essential component of the design and one in which we see some variation even when the panel treatment is the same. Rib scales are not the only design element of course, but it is an essential one and one that gets modified routinely for different reasons. 

I have researched rib scales for decades as you know. I have analyzed scales of roughly a thousand soundboards. I even have a couple of your scales, LOL So i can confidently say your approach is wrong and your premise is flawed. One can only conclude that you are unsatisfied with the results you have obtained up until now, and wanting to improve your craft, but the idea of  getting a "more balanced sound" by minutely changing rib scales will be fruitless i'm afraid. 

Another flaw is to ask others for their rib scales. Every rib scale i have that i hold of high value, are boards that i listened to before and after i rebuilt them. So when you get a rib scale from others you wont have that necessary input to go with it. So just going by numbers is meaningless. See what i mean? And that is just one example.

-chris

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

Last time you "weighed in" you claimed to have reduced mass by 6 lbs in an average board. Still waiting for you to disclose exactly where that weight comes from. I've asked several times with no response. Six lbs is about the weight of half the ribs in the board btw.  I have my doubts about such claims. 

Your other comments I won't dignify by responding to except to say it's not very in keeping with expected behavior on this list. Nor are your advertisements contained in your signature, btw. You might double check the rules of engagement here before someone else does. 

I too have been collecting data and analyzing soundboards for decades though not without input and discussion from other techs and engineers over these many years. I try and get out of my own bubble once in awhile.  My interest remains and I hope others who may wish to participate are not discouraged by your specious and antagonistic claims. 

The purpose of this is to see how uniform executions are between similar sized pianos with similar string scales, if not the exact same model. Why I'm doing it this way I'd be happy to explain to anyone interested.

The rib scale remains an essential component of the design and one in which we see some variation even when the panel treatment is the same. Rib scales are not the only design element of course, but it is an essential one and one that gets modified routinely for different reasons. 

I have researched rib scales for decades as you know. I have analyzed scales of roughly a thousand soundboards. I even have a couple of your scales, LOL So i can confidently say your approach is wrong and your premise is flawed. One can only conclude that you are unsatisfied with the results you have obtained up until now, and wanting to improve your craft, but the idea of  getting a "more balanced sound" by minutely changing rib scales will be fruitless i'm afraid. 

Another flaw is to ask others for their rib scales. Every rib scale i have that i hold of high value, are boards that i listened to before and after i rebuilt them. So when you get a rib scale from others you wont have that necessary input to go with it. So just going by numbers is meaningless. See what i mean? And that is just one example.

-chris

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

David,

I bit off topic, but your comment, "I too have been collecting data and analyzing soundboards for decades though not without input and discussion from other techs and engineers over these many years" triggered my understanding of the importance of working out problems without the input of past or established norms. When I researched the False Beat phenomenon, I mostly ignored past theories and framed my own platform utilizing my general knowledge of physics. This approach was bolstered when, after completing my research, I searched on ChatGPT, an AI search engine, to read what others had to say about the subject. Pushing aside outright errors I believe my research may have been greatly strangled had my mind been cluttered with, specious statements by so-called authorities.

Not to discount input from others, but I believe new ideas come first from within and then compared with others.

Last time you "weighed in" you claimed to have reduced mass by 6 lbs in an average board. Still waiting for you to disclose exactly where that weight comes from. I've asked several times with no response. Six lbs is about the weight of half the ribs in the board btw.  I have my doubts about such claims. 

Your other comments I won't dignify by responding to except to say it's not very in keeping with expected behavior on this list. Nor are your advertisements contained in your signature, btw. You might double check the rules of engagement here before someone else does. 

I too have been collecting data and analyzing soundboards for decades though not without input and discussion from other techs and engineers over these many years. I try and get out of my own bubble once in awhile.  My interest remains and I hope others who may wish to participate are not discouraged by your specious and antagonistic claims. 

The purpose of this is to see how uniform executions are between similar sized pianos with similar string scales, if not the exact same model. Why I'm doing it this way I'd be happy to explain to anyone interested.

The rib scale remains an essential component of the design and one in which we see some variation even when the panel treatment is the same. Rib scales are not the only design element of course, but it is an essential one and one that gets modified routinely for different reasons. 

I have researched rib scales for decades as you know. I have analyzed scales of roughly a thousand soundboards. I even have a couple of your scales, LOL So i can confidently say your approach is wrong and your premise is flawed. One can only conclude that you are unsatisfied with the results you have obtained up until now, and wanting to improve your craft, but the idea of  getting a "more balanced sound" by minutely changing rib scales will be fruitless i'm afraid. 

Another flaw is to ask others for their rib scales. Every rib scale i have that i hold of high value, are boards that i listened to before and after i rebuilt them. So when you get a rib scale from others you wont have that necessary input to go with it. So just going by numbers is meaningless. See what i mean? And that is just one example.

-chris

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

David,

I bit off topic, but your comment, "I too have been collecting data and analyzing soundboards for decades though not without input and discussion from other techs and engineers over these many years" triggered my understanding of the importance of working out problems without the input of past or established norms. When I researched the False Beat phenomenon, I mostly ignored past theories and framed my own platform utilizing my general knowledge of physics. This approach was bolstered when, after completing my research, I searched on ChatGPT, an AI search engine, to read what others had to say about the subject. Pushing aside outright errors I believe my research may have been greatly strangled had my mind been cluttered with, specious statements by so-called authorities.

Not to discount input from others, but I believe new ideas come first from within and then compared with others.

Last time you "weighed in" you claimed to have reduced mass by 6 lbs in an average board. Still waiting for you to disclose exactly where that weight comes from. I've asked several times with no response. Six lbs is about the weight of half the ribs in the board btw.  I have my doubts about such claims. 

Your other comments I won't dignify by responding to except to say it's not very in keeping with expected behavior on this list. Nor are your advertisements contained in your signature, btw. You might double check the rules of engagement here before someone else does. 

I too have been collecting data and analyzing soundboards for decades though not without input and discussion from other techs and engineers over these many years. I try and get out of my own bubble once in awhile.  My interest remains and I hope others who may wish to participate are not discouraged by your specious and antagonistic claims. 

The purpose of this is to see how uniform executions are between similar sized pianos with similar string scales, if not the exact same model. Why I'm doing it this way I'd be happy to explain to anyone interested.

The rib scale remains an essential component of the design and one in which we see some variation even when the panel treatment is the same. Rib scales are not the only design element of course, but it is an essential one and one that gets modified routinely for different reasons. 

I have researched rib scales for decades as you know. I have analyzed scales of roughly a thousand soundboards. I even have a couple of your scales, LOL So i can confidently say your approach is wrong and your premise is flawed. One can only conclude that you are unsatisfied with the results you have obtained up until now, and wanting to improve your craft, but the idea of  getting a "more balanced sound" by minutely changing rib scales will be fruitless i'm afraid. 

Another flaw is to ask others for their rib scales. Every rib scale i have that i hold of high value, are boards that i listened to before and after i rebuilt them. So when you get a rib scale from others you wont have that necessary input to go with it. So just going by numbers is meaningless. See what i mean? And that is just one example.

-chris

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

David,

I bit off topic, but your comment, "I too have been collecting data and analyzing soundboards for decades though not without input and discussion from other techs and engineers over these many years" triggered my understanding of the importance of working out problems without the input of past or established norms. When I researched the False Beat phenomenon, I mostly ignored past theories and framed my own platform utilizing my general knowledge of physics. This approach was bolstered when, after completing my research, I searched on ChatGPT, an AI search engine, to read what others had to say about the subject. Pushing aside outright errors I believe my research may have been greatly strangled had my mind been cluttered with, specious statements by so-called authorities.

Not to discount input from others, but I believe new ideas come first from within and then compared with others.

Last time you "weighed in" you claimed to have reduced mass by 6 lbs in an average board. Still waiting for you to disclose exactly where that weight comes from. I've asked several times with no response. Six lbs is about the weight of half the ribs in the board btw.  I have my doubts about such claims. 

Your other comments I won't dignify by responding to except to say it's not very in keeping with expected behavior on this list. Nor are your advertisements contained in your signature, btw. You might double check the rules of engagement here before someone else does. 

I too have been collecting data and analyzing soundboards for decades though not without input and discussion from other techs and engineers over these many years. I try and get out of my own bubble once in awhile.  My interest remains and I hope others who may wish to participate are not discouraged by your specious and antagonistic claims. 

The purpose of this is to see how uniform executions are between similar sized pianos with similar string scales, if not the exact same model. Why I'm doing it this way I'd be happy to explain to anyone interested.

The rib scale remains an essential component of the design and one in which we see some variation even when the panel treatment is the same. Rib scales are not the only design element of course, but it is an essential one and one that gets modified routinely for different reasons. 

I have researched rib scales for decades as you know. I have analyzed scales of roughly a thousand soundboards. I even have a couple of your scales, LOL So i can confidently say your approach is wrong and your premise is flawed. One can only conclude that you are unsatisfied with the results you have obtained up until now, and wanting to improve your craft, but the idea of  getting a "more balanced sound" by minutely changing rib scales will be fruitless i'm afraid. 

Another flaw is to ask others for their rib scales. Every rib scale i have that i hold of high value, are boards that i listened to before and after i rebuilt them. So when you get a rib scale from others you wont have that necessary input to go with it. So just going by numbers is meaningless. See what i mean? And that is just one example.

-chris

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

The PDF with the comparison charts that I posted accounts for the difference in species from Pine to White spruce. The difference between those two species is mostly in the modulus.  That explanation is included in the PDF.  Some people are using laminated ribs, or were, and I don't know how those respond compared to non-Laminated. I've never seen a study. Different sawing patterns I have not taken into account as I am unaware of any differences in approach. 

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

The way lumber is cut has a great effect on performance under stress such as downbearing pressure.

The PDF with the comparison charts that I posted accounts for the difference in species from Pine to White spruce. The difference between those two species is mostly in the modulus.  That explanation is included in the PDF.  Some people are using laminated ribs, or were, and I don't know how those respond compared to non-Laminated. I've never seen a study. Different sawing patterns I have not taken into account as I am unaware of any differences in approach. 

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

I don't know if it has a "great effect".  The modulus doesn't change with different sawing techniques as far as I know.   However, quarter sawn, versus flat sawn, is more stable across the grain.  Because of that, soundboard flitches tend to be quarter sawn which will result in more stability during humidity changes (which isn't to say they don't still change).  Rib stock comes both ways but it should be noted that rib strength is more a function of what happens along the grain.  In that sense I don't think it has much effect on deflection under load. 

I know that Del Fandrich has encouraged the use of laminated ribs to take some of the variability out of any particular piece of wood.  As far as I can tell laminated ribs have the same modulus as non-laminated ribs but there can be factors that contribute to differences.  Those would include any irregularities in a single piece of wood that might contribute to weaker areas, how the grain is oriented in the laminae, and the adhesive, depending on what it is, might also create some additional stiffness.    

The way lumber is cut has a great effect on performance under stress such as downbearing pressure.

The PDF with the comparison charts that I posted accounts for the difference in species from Pine to White spruce. The difference between those two species is mostly in the modulus.  That explanation is included in the PDF.  Some people are using laminated ribs, or were, and I don't know how those respond compared to non-Laminated. I've never seen a study. Different sawing patterns I have not taken into account as I am unaware of any differences in approach. 

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

David et al,

I don't rebuild and I am not the best person to evaluate different pianos for sound quality, "singing", loudness or any other measure.  I mostly try to make the piano in front of me sound as good as possible within my customer's budget.  But I would like to insert my 2 cents.

When anyone of us makes a change to a piano, whether by voicing, regulating or rebuilding we are making a change to only a single instrument. This tends to be an anecdote.  A proper "scientific" study needs tightly controlled external factors (controls) and repetitions, something that only manufacturer can do.  I do realize that some of us have rebuilt vast numbers of instruments, however, unless we are only working on a specific model of a specific brand, ideally pianos that have undergone the same environmental conditions we are not really doing repetitions, only more anecdotes.

A statistical eye opener I stumbled across was a target shooter who analyzed the common practice of shooting 5 shots at a target to evaluate a particular load of cartridge (bullet weight, powder amount, etc.)  When many such 5 shot groups were actually compared it was found that 5 shots were far from conclusive, in fact, the number of shots necessary to properly evaluate a cartridge would probably wear out the barrel of the gun before a conclusion. (https://www.youtube.com/watch?v=JSxr9AHER_s&t=647s).

I am not suggesting that any rebuilder does not know what they are doing or that their inventions or improvements aren't wonderful, only that, aside from a manufacturer, who can control most of the many variables that go into a piano, the changes that we as individual rebuilders are still anecdotes.  If our newly rebuilt Bosenchickway sounds great then we and our customer are happy. If it falls short of our goal then we either make further modifications or work on the hammers.

We have a vast history of instruments behind us. Items such as hammer weight, action spread, key weighting, soundboard thickness... all the long list of variables that we face as techs have long been done and we can pick among the glorious instruments of the past for their successes and failures.  And we can study the modern manufacturer's techniques and chose which to emulate or avoid.  Our most wonderful computer programs only produce suggestions, we would need to carefully replicate any one change over many pianos to get an accurate idea of if our improvements are really improvements.

I don't know if it has a "great effect".  The modulus doesn't change with different sawing techniques as far as I know.   However, quarter sawn, versus flat sawn, is more stable across the grain.  Because of that, soundboard flitches tend to be quarter sawn which will result in more stability during humidity changes (which isn't to say they don't still change).  Rib stock comes both ways but it should be noted that rib strength is more a function of what happens along the grain.  In that sense I don't think it has much effect on deflection under load. 

I know that Del Fandrich has encouraged the use of laminated ribs to take some of the variability out of any particular piece of wood.  As far as I can tell laminated ribs have the same modulus as non-laminated ribs but there can be factors that contribute to differences.  Those would include any irregularities in a single piece of wood that might contribute to weaker areas, how the grain is oriented in the laminae, and the adhesive, depending on what it is, might also create some additional stiffness.    

The way lumber is cut has a great effect on performance under stress such as downbearing pressure.

The PDF with the comparison charts that I posted accounts for the difference in species from Pine to White spruce. The difference between those two species is mostly in the modulus.  That explanation is included in the PDF.  Some people are using laminated ribs, or were, and I don't know how those respond compared to non-Laminated. I've never seen a study. Different sawing patterns I have not taken into account as I am unaware of any differences in approach. 

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

Blaine

I'm not exactly sure what your point is.  I'm collecting data on rib scales to see how consistent they are and how they might vary between pianos. I'm also showing how rib scales might undergo small tweaks to get them to comport with some basic engineering principles. (Spoiler alert, I'm not the only one who does this).  

How you get from there to "Bosenchickway", which seems a pretty derogatory reference, I'm not sure.

I would not say that what I'm doing is "anecdotal". I would say it's hard to extrapolate the effect of a single change even using scientific methodology in a piano because it's impossible to really make only a single change. That's especially true in the case of a rib scale because it requires other changes, like installing that new rib scale in a brand new soundboard panel--at least. 

but it sounds like you're operating under fear of making any changes at all because of that. Yet you don't hesitate to change the consistency of a hammer when you find it to be a problem, voicing. You don't hesitate to change the touch weight if you find it to be a problem by some objective measure, you don't hesitate to put on a new hammer that's different from the original.  So I'm not really sure what you're getting at.  

But speaking of anecdotes, I recall being asked to come and assess a piano for someone who was concerned because the piano sounded really bad. It turned out the soundboard was toast, ribs were coming unglued, the board had no crown, gaping cracks throughout, a Steinway by the way. I told the customer that it needed a new soundboard, that this one had deteriorated to the point where it couldn't be salvaged and was responsible for the way the piano sounded. She's looked at me and said, "but will putting in a new soundboard change the sound of the piano?".  My response was, "you better hope so"!

David et al,

I don't rebuild and I am not the best person to evaluate different pianos for sound quality, "singing", loudness or any other measure.  I mostly try to make the piano in front of me sound as good as possible within my customer's budget.  But I would like to insert my 2 cents.

When anyone of us makes a change to a piano, whether by voicing, regulating or rebuilding we are making a change to only a single instrument. This tends to be an anecdote.  A proper "scientific" study needs tightly controlled external factors (controls) and repetitions, something that only manufacturer can do.  I do realize that some of us have rebuilt vast numbers of instruments, however, unless we are only working on a specific model of a specific brand, ideally pianos that have undergone the same environmental conditions we are not really doing repetitions, only more anecdotes.

A statistical eye opener I stumbled across was a target shooter who analyzed the common practice of shooting 5 shots at a target to evaluate a particular load of cartridge (bullet weight, powder amount, etc.)  When many such 5 shot groups were actually compared it was found that 5 shots were far from conclusive, in fact, the number of shots necessary to properly evaluate a cartridge would probably wear out the barrel of the gun before a conclusion. (https://www.youtube.com/watch?v=JSxr9AHER_s&t=647s).

I am not suggesting that any rebuilder does not know what they are doing or that their inventions or improvements aren't wonderful, only that, aside from a manufacturer, who can control most of the many variables that go into a piano, the changes that we as individual rebuilders are still anecdotes.  If our newly rebuilt Bosenchickway sounds great then we and our customer are happy. If it falls short of our goal then we either make further modifications or work on the hammers.

We have a vast history of instruments behind us. Items such as hammer weight, action spread, key weighting, soundboard thickness... all the long list of variables that we face as techs have long been done and we can pick among the glorious instruments of the past for their successes and failures.  And we can study the modern manufacturer's techniques and chose which to emulate or avoid.  Our most wonderful computer programs only produce suggestions, we would need to carefully replicate any one change over many pianos to get an accurate idea of if our improvements are really improvements.

I don't know if it has a "great effect".  The modulus doesn't change with different sawing techniques as far as I know.   However, quarter sawn, versus flat sawn, is more stable across the grain.  Because of that, soundboard flitches tend to be quarter sawn which will result in more stability during humidity changes (which isn't to say they don't still change).  Rib stock comes both ways but it should be noted that rib strength is more a function of what happens along the grain.  In that sense I don't think it has much effect on deflection under load. 

I know that Del Fandrich has encouraged the use of laminated ribs to take some of the variability out of any particular piece of wood.  As far as I can tell laminated ribs have the same modulus as non-laminated ribs but there can be factors that contribute to differences.  Those would include any irregularities in a single piece of wood that might contribute to weaker areas, how the grain is oriented in the laminae, and the adhesive, depending on what it is, might also create some additional stiffness.    

The way lumber is cut has a great effect on performance under stress such as downbearing pressure.

The PDF with the comparison charts that I posted accounts for the difference in species from Pine to White spruce. The difference between those two species is mostly in the modulus.  That explanation is included in the PDF.  Some people are using laminated ribs, or were, and I don't know how those respond compared to non-Laminated. I've never seen a study. Different sawing patterns I have not taken into account as I am unaware of any differences in approach. 

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

Read any good book on wood engineering and you will find that in the case of a solid wood beam suspended between two points with pressure applied

at midpoint that the quartersawn or vertical grain beam will be vastly more resistive to downward force that flat or rift sawn.

Blaine

I'm not exactly sure what your point is.  I'm collecting data on rib scales to see how consistent they are and how they might vary between pianos. I'm also showing how rib scales might undergo small tweaks to get them to comport with some basic engineering principles. (Spoiler alert, I'm not the only one who does this).  

How you get from there to "Bosenchickway", which seems a pretty derogatory reference, I'm not sure.

I would not say that what I'm doing is "anecdotal". I would say it's hard to extrapolate the effect of a single change even using scientific methodology in a piano because it's impossible to really make only a single change. That's especially true in the case of a rib scale because it requires other changes, like installing that new rib scale in a brand new soundboard panel--at least. 

but it sounds like you're operating under fear of making any changes at all because of that. Yet you don't hesitate to change the consistency of a hammer when you find it to be a problem, voicing. You don't hesitate to change the touch weight if you find it to be a problem by some objective measure, you don't hesitate to put on a new hammer that's different from the original.  So I'm not really sure what you're getting at.  

But speaking of anecdotes, I recall being asked to come and assess a piano for someone who was concerned because the piano sounded really bad. It turned out the soundboard was toast, ribs were coming unglued, the board had no crown, gaping cracks throughout, a Steinway by the way. I told the customer that it needed a new soundboard, that this one had deteriorated to the point where it couldn't be salvaged and was responsible for the way the piano sounded. She's looked at me and said, "but will putting in a new soundboard change the sound of the piano?".  My response was, "you better hope so"!

David et al,

I don't rebuild and I am not the best person to evaluate different pianos for sound quality, "singing", loudness or any other measure.  I mostly try to make the piano in front of me sound as good as possible within my customer's budget.  But I would like to insert my 2 cents.

When anyone of us makes a change to a piano, whether by voicing, regulating or rebuilding we are making a change to only a single instrument. This tends to be an anecdote.  A proper "scientific" study needs tightly controlled external factors (controls) and repetitions, something that only manufacturer can do.  I do realize that some of us have rebuilt vast numbers of instruments, however, unless we are only working on a specific model of a specific brand, ideally pianos that have undergone the same environmental conditions we are not really doing repetitions, only more anecdotes.

A statistical eye opener I stumbled across was a target shooter who analyzed the common practice of shooting 5 shots at a target to evaluate a particular load of cartridge (bullet weight, powder amount, etc.)  When many such 5 shot groups were actually compared it was found that 5 shots were far from conclusive, in fact, the number of shots necessary to properly evaluate a cartridge would probably wear out the barrel of the gun before a conclusion. (https://www.youtube.com/watch?v=JSxr9AHER_s&t=647s).

I am not suggesting that any rebuilder does not know what they are doing or that their inventions or improvements aren't wonderful, only that, aside from a manufacturer, who can control most of the many variables that go into a piano, the changes that we as individual rebuilders are still anecdotes.  If our newly rebuilt Bosenchickway sounds great then we and our customer are happy. If it falls short of our goal then we either make further modifications or work on the hammers.

We have a vast history of instruments behind us. Items such as hammer weight, action spread, key weighting, soundboard thickness... all the long list of variables that we face as techs have long been done and we can pick among the glorious instruments of the past for their successes and failures.  And we can study the modern manufacturer's techniques and chose which to emulate or avoid.  Our most wonderful computer programs only produce suggestions, we would need to carefully replicate any one change over many pianos to get an accurate idea of if our improvements are really improvements.

I don't know if it has a "great effect".  The modulus doesn't change with different sawing techniques as far as I know.   However, quarter sawn, versus flat sawn, is more stable across the grain.  Because of that, soundboard flitches tend to be quarter sawn which will result in more stability during humidity changes (which isn't to say they don't still change).  Rib stock comes both ways but it should be noted that rib strength is more a function of what happens along the grain.  In that sense I don't think it has much effect on deflection under load. 

I know that Del Fandrich has encouraged the use of laminated ribs to take some of the variability out of any particular piece of wood.  As far as I can tell laminated ribs have the same modulus as non-laminated ribs but there can be factors that contribute to differences.  Those would include any irregularities in a single piece of wood that might contribute to weaker areas, how the grain is oriented in the laminae, and the adhesive, depending on what it is, might also create some additional stiffness.    

The way lumber is cut has a great effect on performance under stress such as downbearing pressure.

The PDF with the comparison charts that I posted accounts for the difference in species from Pine to White spruce. The difference between those two species is mostly in the modulus.  That explanation is included in the PDF.  Some people are using laminated ribs, or were, and I don't know how those respond compared to non-Laminated. I've never seen a study. Different sawing patterns I have not taken into account as I am unaware of any differences in approach. 

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

I find no reference in Hoadley and a quick internet search turned up this. Csn you show me your citations?

https://www.liutaiomottola.com/myth/quartersawn.htm

Read any good book on wood engineering and you will find that in the case of a solid wood beam suspended between two points with pressure applied

at midpoint that the quartersawn or vertical grain beam will be vastly more resistive to downward force that flat or rift sawn.

Blaine

I'm not exactly sure what your point is.  I'm collecting data on rib scales to see how consistent they are and how they might vary between pianos. I'm also showing how rib scales might undergo small tweaks to get them to comport with some basic engineering principles. (Spoiler alert, I'm not the only one who does this).  

How you get from there to "Bosenchickway", which seems a pretty derogatory reference, I'm not sure.

I would not say that what I'm doing is "anecdotal". I would say it's hard to extrapolate the effect of a single change even using scientific methodology in a piano because it's impossible to really make only a single change. That's especially true in the case of a rib scale because it requires other changes, like installing that new rib scale in a brand new soundboard panel--at least. 

but it sounds like you're operating under fear of making any changes at all because of that. Yet you don't hesitate to change the consistency of a hammer when you find it to be a problem, voicing. You don't hesitate to change the touch weight if you find it to be a problem by some objective measure, you don't hesitate to put on a new hammer that's different from the original.  So I'm not really sure what you're getting at.  

But speaking of anecdotes, I recall being asked to come and assess a piano for someone who was concerned because the piano sounded really bad. It turned out the soundboard was toast, ribs were coming unglued, the board had no crown, gaping cracks throughout, a Steinway by the way. I told the customer that it needed a new soundboard, that this one had deteriorated to the point where it couldn't be salvaged and was responsible for the way the piano sounded. She's looked at me and said, "but will putting in a new soundboard change the sound of the piano?".  My response was, "you better hope so"!

David et al,

I don't rebuild and I am not the best person to evaluate different pianos for sound quality, "singing", loudness or any other measure.  I mostly try to make the piano in front of me sound as good as possible within my customer's budget.  But I would like to insert my 2 cents.

When anyone of us makes a change to a piano, whether by voicing, regulating or rebuilding we are making a change to only a single instrument. This tends to be an anecdote.  A proper "scientific" study needs tightly controlled external factors (controls) and repetitions, something that only manufacturer can do.  I do realize that some of us have rebuilt vast numbers of instruments, however, unless we are only working on a specific model of a specific brand, ideally pianos that have undergone the same environmental conditions we are not really doing repetitions, only more anecdotes.

A statistical eye opener I stumbled across was a target shooter who analyzed the common practice of shooting 5 shots at a target to evaluate a particular load of cartridge (bullet weight, powder amount, etc.)  When many such 5 shot groups were actually compared it was found that 5 shots were far from conclusive, in fact, the number of shots necessary to properly evaluate a cartridge would probably wear out the barrel of the gun before a conclusion. (https://www.youtube.com/watch?v=JSxr9AHER_s&t=647s).

I am not suggesting that any rebuilder does not know what they are doing or that their inventions or improvements aren't wonderful, only that, aside from a manufacturer, who can control most of the many variables that go into a piano, the changes that we as individual rebuilders are still anecdotes.  If our newly rebuilt Bosenchickway sounds great then we and our customer are happy. If it falls short of our goal then we either make further modifications or work on the hammers.

We have a vast history of instruments behind us. Items such as hammer weight, action spread, key weighting, soundboard thickness... all the long list of variables that we face as techs have long been done and we can pick among the glorious instruments of the past for their successes and failures.  And we can study the modern manufacturer's techniques and chose which to emulate or avoid.  Our most wonderful computer programs only produce suggestions, we would need to carefully replicate any one change over many pianos to get an accurate idea of if our improvements are really improvements.

I don't know if it has a "great effect".  The modulus doesn't change with different sawing techniques as far as I know.   However, quarter sawn, versus flat sawn, is more stable across the grain.  Because of that, soundboard flitches tend to be quarter sawn which will result in more stability during humidity changes (which isn't to say they don't still change).  Rib stock comes both ways but it should be noted that rib strength is more a function of what happens along the grain.  In that sense I don't think it has much effect on deflection under load. 

I know that Del Fandrich has encouraged the use of laminated ribs to take some of the variability out of any particular piece of wood.  As far as I can tell laminated ribs have the same modulus as non-laminated ribs but there can be factors that contribute to differences.  Those would include any irregularities in a single piece of wood that might contribute to weaker areas, how the grain is oriented in the laminae, and the adhesive, depending on what it is, might also create some additional stiffness.    

The way lumber is cut has a great effect on performance under stress such as downbearing pressure.

The PDF with the comparison charts that I posted accounts for the difference in species from Pine to White spruce. The difference between those two species is mostly in the modulus.  That explanation is included in the PDF.  Some people are using laminated ribs, or were, and I don't know how those respond compared to non-Laminated. I've never seen a study. Different sawing patterns I have not taken into account as I am unaware of any differences in approach. 

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

I'll pursue this further and see what I find.  So far, I can find no information suggesting that the MOE is different depending on the way the wood is sawn.  As I said before, it does affect stability but not sure that's important in a rib of these dimensions.  In the soundboard panel, quarter sawn will have distinct advantages.  I sent a message to Bolduc asking about their rib stock, how they cut it and if they are aware of differences in MOE which are dependent on that.  I clearly have some pieces that are flat sawn and I know that quarter sawing is much more wasteful.  

One thing that does come up in Hoadley are significant differences between pieces of wood from the same species in terms of strength and this difference can be quite significant depending on several factors.  I know that Del Fandrich took this into consideration when deciding to use laminated ribs, the goal being to combine laminae from different pieces of wood and mitigate those differences.  

I find no reference in Hoadley and a quick internet search turned up this. Csn you show me your citations?

https://www.liutaiomottola.com/myth/quartersawn.htm

Read any good book on wood engineering and you will find that in the case of a solid wood beam suspended between two points with pressure applied

at midpoint that the quartersawn or vertical grain beam will be vastly more resistive to downward force that flat or rift sawn.

Blaine

I'm not exactly sure what your point is.  I'm collecting data on rib scales to see how consistent they are and how they might vary between pianos. I'm also showing how rib scales might undergo small tweaks to get them to comport with some basic engineering principles. (Spoiler alert, I'm not the only one who does this).  

How you get from there to "Bosenchickway", which seems a pretty derogatory reference, I'm not sure.

I would not say that what I'm doing is "anecdotal". I would say it's hard to extrapolate the effect of a single change even using scientific methodology in a piano because it's impossible to really make only a single change. That's especially true in the case of a rib scale because it requires other changes, like installing that new rib scale in a brand new soundboard panel--at least. 

but it sounds like you're operating under fear of making any changes at all because of that. Yet you don't hesitate to change the consistency of a hammer when you find it to be a problem, voicing. You don't hesitate to change the touch weight if you find it to be a problem by some objective measure, you don't hesitate to put on a new hammer that's different from the original.  So I'm not really sure what you're getting at.  

But speaking of anecdotes, I recall being asked to come and assess a piano for someone who was concerned because the piano sounded really bad. It turned out the soundboard was toast, ribs were coming unglued, the board had no crown, gaping cracks throughout, a Steinway by the way. I told the customer that it needed a new soundboard, that this one had deteriorated to the point where it couldn't be salvaged and was responsible for the way the piano sounded. She's looked at me and said, "but will putting in a new soundboard change the sound of the piano?".  My response was, "you better hope so"!

David et al,

I don't rebuild and I am not the best person to evaluate different pianos for sound quality, "singing", loudness or any other measure.  I mostly try to make the piano in front of me sound as good as possible within my customer's budget.  But I would like to insert my 2 cents.

When anyone of us makes a change to a piano, whether by voicing, regulating or rebuilding we are making a change to only a single instrument. This tends to be an anecdote.  A proper "scientific" study needs tightly controlled external factors (controls) and repetitions, something that only manufacturer can do.  I do realize that some of us have rebuilt vast numbers of instruments, however, unless we are only working on a specific model of a specific brand, ideally pianos that have undergone the same environmental conditions we are not really doing repetitions, only more anecdotes.

A statistical eye opener I stumbled across was a target shooter who analyzed the common practice of shooting 5 shots at a target to evaluate a particular load of cartridge (bullet weight, powder amount, etc.)  When many such 5 shot groups were actually compared it was found that 5 shots were far from conclusive, in fact, the number of shots necessary to properly evaluate a cartridge would probably wear out the barrel of the gun before a conclusion. (https://www.youtube.com/watch?v=JSxr9AHER_s&t=647s).

I am not suggesting that any rebuilder does not know what they are doing or that their inventions or improvements aren't wonderful, only that, aside from a manufacturer, who can control most of the many variables that go into a piano, the changes that we as individual rebuilders are still anecdotes.  If our newly rebuilt Bosenchickway sounds great then we and our customer are happy. If it falls short of our goal then we either make further modifications or work on the hammers.

We have a vast history of instruments behind us. Items such as hammer weight, action spread, key weighting, soundboard thickness... all the long list of variables that we face as techs have long been done and we can pick among the glorious instruments of the past for their successes and failures.  And we can study the modern manufacturer's techniques and chose which to emulate or avoid.  Our most wonderful computer programs only produce suggestions, we would need to carefully replicate any one change over many pianos to get an accurate idea of if our improvements are really improvements.

I don't know if it has a "great effect".  The modulus doesn't change with different sawing techniques as far as I know.   However, quarter sawn, versus flat sawn, is more stable across the grain.  Because of that, soundboard flitches tend to be quarter sawn which will result in more stability during humidity changes (which isn't to say they don't still change).  Rib stock comes both ways but it should be noted that rib strength is more a function of what happens along the grain.  In that sense I don't think it has much effect on deflection under load. 

I know that Del Fandrich has encouraged the use of laminated ribs to take some of the variability out of any particular piece of wood.  As far as I can tell laminated ribs have the same modulus as non-laminated ribs but there can be factors that contribute to differences.  Those would include any irregularities in a single piece of wood that might contribute to weaker areas, how the grain is oriented in the laminae, and the adhesive, depending on what it is, might also create some additional stiffness.    

The way lumber is cut has a great effect on performance under stress such as downbearing pressure.

The PDF with the comparison charts that I posted accounts for the difference in species from Pine to White spruce. The difference between those two species is mostly in the modulus.  That explanation is included in the PDF.  Some people are using laminated ribs, or were, and I don't know how those respond compared to non-Laminated. I've never seen a study. Different sawing patterns I have not taken into account as I am unaware of any differences in approach. 

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

Here are two more problems with this attempt by the poster.

1} Measuring: Ribs (especially Steinway) were planed by hand. This is why the varying dimensions. Also by asking for co-conspiring dimensions this will just add to the complexity because they are not perfect dimensions across the rib length in both length and width. Another factor is length, each rib has 3 lengths because they are at angles (left side, middle, right side).

And the rib dimensions for engineering are not the important factor for control. I'll explain:

2} The scallop dilemma: I have done numerous tests (with videos somewhere on my channel- for those "peer review" sticklers) that the scalloping controls the deflection values of the entire rib not the dimensions of the rib per se. So when you couple the scalloping issue, with the dimension issue, and the species issue. 

Asking for just dimensions by themselves will work against the poster once he realizes it.

just trying to help.

-chris

I'll pursue this further and see what I find.  So far, I can find no information suggesting that the MOE is different depending on the way the wood is sawn.  As I said before, it does affect stability but not sure that's important in a rib of these dimensions.  In the soundboard panel, quarter sawn will have distinct advantages.  I sent a message to Bolduc asking about their rib stock, how they cut it and if they are aware of differences in MOE which are dependent on that.  I clearly have some pieces that are flat sawn and I know that quarter sawing is much more wasteful.  

One thing that does come up in Hoadley are significant differences between pieces of wood from the same species in terms of strength and this difference can be quite significant depending on several factors.  I know that Del Fandrich took this into consideration when deciding to use laminated ribs, the goal being to combine laminae from different pieces of wood and mitigate those differences.  

I find no reference in Hoadley and a quick internet search turned up this. Csn you show me your citations?

https://www.liutaiomottola.com/myth/quartersawn.htm

Read any good book on wood engineering and you will find that in the case of a solid wood beam suspended between two points with pressure applied

at midpoint that the quartersawn or vertical grain beam will be vastly more resistive to downward force that flat or rift sawn.

Blaine

I'm not exactly sure what your point is.  I'm collecting data on rib scales to see how consistent they are and how they might vary between pianos. I'm also showing how rib scales might undergo small tweaks to get them to comport with some basic engineering principles. (Spoiler alert, I'm not the only one who does this).  

How you get from there to "Bosenchickway", which seems a pretty derogatory reference, I'm not sure.

I would not say that what I'm doing is "anecdotal". I would say it's hard to extrapolate the effect of a single change even using scientific methodology in a piano because it's impossible to really make only a single change. That's especially true in the case of a rib scale because it requires other changes, like installing that new rib scale in a brand new soundboard panel--at least. 

but it sounds like you're operating under fear of making any changes at all because of that. Yet you don't hesitate to change the consistency of a hammer when you find it to be a problem, voicing. You don't hesitate to change the touch weight if you find it to be a problem by some objective measure, you don't hesitate to put on a new hammer that's different from the original.  So I'm not really sure what you're getting at.  

But speaking of anecdotes, I recall being asked to come and assess a piano for someone who was concerned because the piano sounded really bad. It turned out the soundboard was toast, ribs were coming unglued, the board had no crown, gaping cracks throughout, a Steinway by the way. I told the customer that it needed a new soundboard, that this one had deteriorated to the point where it couldn't be salvaged and was responsible for the way the piano sounded. She's looked at me and said, "but will putting in a new soundboard change the sound of the piano?".  My response was, "you better hope so"!

David et al,

I don't rebuild and I am not the best person to evaluate different pianos for sound quality, "singing", loudness or any other measure.  I mostly try to make the piano in front of me sound as good as possible within my customer's budget.  But I would like to insert my 2 cents.

When anyone of us makes a change to a piano, whether by voicing, regulating or rebuilding we are making a change to only a single instrument. This tends to be an anecdote.  A proper "scientific" study needs tightly controlled external factors (controls) and repetitions, something that only manufacturer can do.  I do realize that some of us have rebuilt vast numbers of instruments, however, unless we are only working on a specific model of a specific brand, ideally pianos that have undergone the same environmental conditions we are not really doing repetitions, only more anecdotes.

A statistical eye opener I stumbled across was a target shooter who analyzed the common practice of shooting 5 shots at a target to evaluate a particular load of cartridge (bullet weight, powder amount, etc.)  When many such 5 shot groups were actually compared it was found that 5 shots were far from conclusive, in fact, the number of shots necessary to properly evaluate a cartridge would probably wear out the barrel of the gun before a conclusion. (https://www.youtube.com/watch?v=JSxr9AHER_s&t=647s).

I am not suggesting that any rebuilder does not know what they are doing or that their inventions or improvements aren't wonderful, only that, aside from a manufacturer, who can control most of the many variables that go into a piano, the changes that we as individual rebuilders are still anecdotes.  If our newly rebuilt Bosenchickway sounds great then we and our customer are happy. If it falls short of our goal then we either make further modifications or work on the hammers.

We have a vast history of instruments behind us. Items such as hammer weight, action spread, key weighting, soundboard thickness... all the long list of variables that we face as techs have long been done and we can pick among the glorious instruments of the past for their successes and failures.  And we can study the modern manufacturer's techniques and chose which to emulate or avoid.  Our most wonderful computer programs only produce suggestions, we would need to carefully replicate any one change over many pianos to get an accurate idea of if our improvements are really improvements.

I don't know if it has a "great effect".  The modulus doesn't change with different sawing techniques as far as I know.   However, quarter sawn, versus flat sawn, is more stable across the grain.  Because of that, soundboard flitches tend to be quarter sawn which will result in more stability during humidity changes (which isn't to say they don't still change).  Rib stock comes both ways but it should be noted that rib strength is more a function of what happens along the grain.  In that sense I don't think it has much effect on deflection under load. 

I know that Del Fandrich has encouraged the use of laminated ribs to take some of the variability out of any particular piece of wood.  As far as I can tell laminated ribs have the same modulus as non-laminated ribs but there can be factors that contribute to differences.  Those would include any irregularities in a single piece of wood that might contribute to weaker areas, how the grain is oriented in the laminae, and the adhesive, depending on what it is, might also create some additional stiffness.    

The way lumber is cut has a great effect on performance under stress such as downbearing pressure.

The PDF with the comparison charts that I posted accounts for the difference in species from Pine to White spruce. The difference between those two species is mostly in the modulus.  That explanation is included in the PDF.  Some people are using laminated ribs, or were, and I don't know how those respond compared to non-Laminated. I've never seen a study. Different sawing patterns I have not taken into account as I am unaware of any differences in approach. 

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

Blaine

I'm not exactly sure what your point is.  I'm collecting data on rib scales to see how consistent they are and how they might vary between pianos. I'm also showing how rib scales might undergo small tweaks to get them to comport with some basic engineering principles. (Spoiler alert, I'm not the only one who does this).  

How you get from there to "Bosenchickway", which seems a pretty derogatory reference, I'm not sure.

I would not say that what I'm doing is "anecdotal". I would say it's hard to extrapolate the effect of a single change even using scientific methodology in a piano because it's impossible to really make only a single change. That's especially true in the case of a rib scale because it requires other changes, like installing that new rib scale in a brand new soundboard panel--at least. 

but it sounds like you're operating under fear of making any changes at all because of that. Yet you don't hesitate to change the consistency of a hammer when you find it to be a problem, voicing. You don't hesitate to change the touch weight if you find it to be a problem by some objective measure, you don't hesitate to put on a new hammer that's different from the original.  So I'm not really sure what you're getting at.  

But speaking of anecdotes, I recall being asked to come and assess a piano for someone who was concerned because the piano sounded really bad. It turned out the soundboard was toast, ribs were coming unglued, the board had no crown, gaping cracks throughout, a Steinway by the way. I told the customer that it needed a new soundboard, that this one had deteriorated to the point where it couldn't be salvaged and was responsible for the way the piano sounded. She's looked at me and said, "but will putting in a new soundboard change the sound of the piano?".  My response was, "you better hope so"!

David et al,

I don't rebuild and I am not the best person to evaluate different pianos for sound quality, "singing", loudness or any other measure.  I mostly try to make the piano in front of me sound as good as possible within my customer's budget.  But I would like to insert my 2 cents.

When anyone of us makes a change to a piano, whether by voicing, regulating or rebuilding we are making a change to only a single instrument. This tends to be an anecdote.  A proper "scientific" study needs tightly controlled external factors (controls) and repetitions, something that only manufacturer can do.  I do realize that some of us have rebuilt vast numbers of instruments, however, unless we are only working on a specific model of a specific brand, ideally pianos that have undergone the same environmental conditions we are not really doing repetitions, only more anecdotes.

A statistical eye opener I stumbled across was a target shooter who analyzed the common practice of shooting 5 shots at a target to evaluate a particular load of cartridge (bullet weight, powder amount, etc.)  When many such 5 shot groups were actually compared it was found that 5 shots were far from conclusive, in fact, the number of shots necessary to properly evaluate a cartridge would probably wear out the barrel of the gun before a conclusion. (https://www.youtube.com/watch?v=JSxr9AHER_s&t=647s).

I am not suggesting that any rebuilder does not know what they are doing or that their inventions or improvements aren't wonderful, only that, aside from a manufacturer, who can control most of the many variables that go into a piano, the changes that we as individual rebuilders are still anecdotes.  If our newly rebuilt Bosenchickway sounds great then we and our customer are happy. If it falls short of our goal then we either make further modifications or work on the hammers.

We have a vast history of instruments behind us. Items such as hammer weight, action spread, key weighting, soundboard thickness... all the long list of variables that we face as techs have long been done and we can pick among the glorious instruments of the past for their successes and failures.  And we can study the modern manufacturer's techniques and chose which to emulate or avoid.  Our most wonderful computer programs only produce suggestions, we would need to carefully replicate any one change over many pianos to get an accurate idea of if our improvements are really improvements.

I don't know if it has a "great effect".  The modulus doesn't change with different sawing techniques as far as I know.   However, quarter sawn, versus flat sawn, is more stable across the grain.  Because of that, soundboard flitches tend to be quarter sawn which will result in more stability during humidity changes (which isn't to say they don't still change).  Rib stock comes both ways but it should be noted that rib strength is more a function of what happens along the grain.  In that sense I don't think it has much effect on deflection under load. 

I know that Del Fandrich has encouraged the use of laminated ribs to take some of the variability out of any particular piece of wood.  As far as I can tell laminated ribs have the same modulus as non-laminated ribs but there can be factors that contribute to differences.  Those would include any irregularities in a single piece of wood that might contribute to weaker areas, how the grain is oriented in the laminae, and the adhesive, depending on what it is, might also create some additional stiffness.    

The way lumber is cut has a great effect on performance under stress such as downbearing pressure.

The PDF with the comparison charts that I posted accounts for the difference in species from Pine to White spruce. The difference between those two species is mostly in the modulus.  That explanation is included in the PDF.  Some people are using laminated ribs, or were, and I don't know how those respond compared to non-Laminated. I've never seen a study. Different sawing patterns I have not taken into account as I am unaware of any differences in approach. 

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

Dave,

I am a piano tuner/tech. Though I trained as a rebuilder early on I have had few opportunities in my 50 years of service to get further into any piano besides regulating, voicing and obvious repairs, so I am not qualified to judge your work.  I talk far more customers out of rebuilding than I sell major work beyond just service.

There is  common psychological issue called cognitive bias; we see what we want to see and chose evidence to support our own beliefs.  This is the reason "Science" has so many rules and procedures, such as double blind studies and statistical analysis.  I run into this myself when I voice a hammer and perceive a beneficial change that may or may not be what I think I hear. I once attended a voicing class and the presenter did a particular technique exclaiming how greatly the sound was improved.  I looked at the tech next to mean we both had the same expression; we didn't hear anything. The proper way to evaluate a piano is to have two identical instruments and to only make a change on one. 

The closest I can get to this is an experiment I did by chalk-marking every other hammer on a set and voicing half of the hammers on one side (the keyboard side) and the other half on the other side. The surprising result was the variability of each hammer, I could perceive a difference, but it wasn't consistent from hammer to hammer, even though I used the same technique as evenly as I could.

My pianist/tuner father once commented that he visited a dealer and was shown to similar grand pianos with close serial numbers.  One was great sounding and the other was disappointing. How often have we had to resolve issues with new pianos on dealer floors with problems when its sister nearby is fine?

I am not criticizing you or any of your work and my "Bosenchickway" was only an attempt at humor.  My point is that we are trying to find a better way to row in a sea of tossing waves and improvements can be hard to verify.

Blaine

I'm not exactly sure what your point is.  I'm collecting data on rib scales to see how consistent they are and how they might vary between pianos. I'm also showing how rib scales might undergo small tweaks to get them to comport with some basic engineering principles. (Spoiler alert, I'm not the only one who does this).  

How you get from there to "Bosenchickway", which seems a pretty derogatory reference, I'm not sure.

I would not say that what I'm doing is "anecdotal". I would say it's hard to extrapolate the effect of a single change even using scientific methodology in a piano because it's impossible to really make only a single change. That's especially true in the case of a rib scale because it requires other changes, like installing that new rib scale in a brand new soundboard panel--at least. 

but it sounds like you're operating under fear of making any changes at all because of that. Yet you don't hesitate to change the consistency of a hammer when you find it to be a problem, voicing. You don't hesitate to change the touch weight if you find it to be a problem by some objective measure, you don't hesitate to put on a new hammer that's different from the original.  So I'm not really sure what you're getting at.  

But speaking of anecdotes, I recall being asked to come and assess a piano for someone who was concerned because the piano sounded really bad. It turned out the soundboard was toast, ribs were coming unglued, the board had no crown, gaping cracks throughout, a Steinway by the way. I told the customer that it needed a new soundboard, that this one had deteriorated to the point where it couldn't be salvaged and was responsible for the way the piano sounded. She's looked at me and said, "but will putting in a new soundboard change the sound of the piano?".  My response was, "you better hope so"!

David et al,

I don't rebuild and I am not the best person to evaluate different pianos for sound quality, "singing", loudness or any other measure.  I mostly try to make the piano in front of me sound as good as possible within my customer's budget.  But I would like to insert my 2 cents.

When anyone of us makes a change to a piano, whether by voicing, regulating or rebuilding we are making a change to only a single instrument. This tends to be an anecdote.  A proper "scientific" study needs tightly controlled external factors (controls) and repetitions, something that only manufacturer can do.  I do realize that some of us have rebuilt vast numbers of instruments, however, unless we are only working on a specific model of a specific brand, ideally pianos that have undergone the same environmental conditions we are not really doing repetitions, only more anecdotes.

A statistical eye opener I stumbled across was a target shooter who analyzed the common practice of shooting 5 shots at a target to evaluate a particular load of cartridge (bullet weight, powder amount, etc.)  When many such 5 shot groups were actually compared it was found that 5 shots were far from conclusive, in fact, the number of shots necessary to properly evaluate a cartridge would probably wear out the barrel of the gun before a conclusion. (https://www.youtube.com/watch?v=JSxr9AHER_s&t=647s).

I am not suggesting that any rebuilder does not know what they are doing or that their inventions or improvements aren't wonderful, only that, aside from a manufacturer, who can control most of the many variables that go into a piano, the changes that we as individual rebuilders are still anecdotes.  If our newly rebuilt Bosenchickway sounds great then we and our customer are happy. If it falls short of our goal then we either make further modifications or work on the hammers.

We have a vast history of instruments behind us. Items such as hammer weight, action spread, key weighting, soundboard thickness... all the long list of variables that we face as techs have long been done and we can pick among the glorious instruments of the past for their successes and failures.  And we can study the modern manufacturer's techniques and chose which to emulate or avoid.  Our most wonderful computer programs only produce suggestions, we would need to carefully replicate any one change over many pianos to get an accurate idea of if our improvements are really improvements.

I don't know if it has a "great effect".  The modulus doesn't change with different sawing techniques as far as I know.   However, quarter sawn, versus flat sawn, is more stable across the grain.  Because of that, soundboard flitches tend to be quarter sawn which will result in more stability during humidity changes (which isn't to say they don't still change).  Rib stock comes both ways but it should be noted that rib strength is more a function of what happens along the grain.  In that sense I don't think it has much effect on deflection under load. 

I know that Del Fandrich has encouraged the use of laminated ribs to take some of the variability out of any particular piece of wood.  As far as I can tell laminated ribs have the same modulus as non-laminated ribs but there can be factors that contribute to differences.  Those would include any irregularities in a single piece of wood that might contribute to weaker areas, how the grain is oriented in the laminae, and the adhesive, depending on what it is, might also create some additional stiffness.    

The way lumber is cut has a great effect on performance under stress such as downbearing pressure.

The PDF with the comparison charts that I posted accounts for the difference in species from Pine to White spruce. The difference between those two species is mostly in the modulus.  That explanation is included in the PDF.  Some people are using laminated ribs, or were, and I don't know how those respond compared to non-Laminated. I've never seen a study. Different sawing patterns I have not taken into account as I am unaware of any differences in approach. 

What about choice of rib material,  spruce vs. sugar pine and mode of cutting:  rift sawn vs. quartersawn.?

Hi Karl

It doesn't matter.  Of course, the dimensions are much easier to measure with the board removed.

The genesis of this is that many techs, when making or ordering a board, simply copy what's there or have Bolduc copy what's there if they are ordering a board in a box.  That's fine to do it that way btw.  Some techs do what I'm doing which is to optimize the ribscale as they see it.  Others, of course, are engaged in total redesign adding cut off bars, changing the number of ribs or the layout.  I have done that but don't anymore.  But I've found some differences when measuring rib dimensions on the same make and model.  Not huge differences but significant.  Whether that's by design or simply something that happens in the factory, I don't know.  As you can see from the pdf I posted that the changes I made to get a little better numbers aren't huge.  They are quite small, in fact, and the way I'm illustrating that with changes in height only you can see exactly what those differences are.  

What I'm looking for is data on various pianos makes and I hope to do side by side comparisons of rib scales on "like" pianos, meaning similar size and similar string scales.  So I might compare a Steinway M with a Yamaha C2, for example, or a Baldwin R.  

Weight is something I have not measured because it's something that's not easily changed without compromising some structural integrity.  BTW on my comments to Chris I didn't take into account that I think he measured the weight of those assemblies to include the bridges (which are relatively heavy).  That makes the ability to reduce weight at that level even more challenging, IMO, because the bridges are a significant part of the overall weight.

So here's an example of the data I'm looking for.  The working length excludes the part of the rib that's glued into the rim.  Millimeters or Inches is fine.  #1 rib is the first rib in the bass.

Mr.Love,

Are you wanting dimensions of the ribs in situ with the board still glued in or after disassembly?

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

David,

Here is an excellent reference:  "Wood Handbook" by the US Forest Products Laboratory.  The pdf is ~14mB.
     https://www.fpl.fs.usda.gov/documnts/fplgtr/fplgtr113/fplgtr113.pdf
  
Check out Table 4-1; The first two columns are of interest.  Flat sawn v/s vertical grain differ (very roughly) by a factor of two.

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

OK thanks John. So tangential would be the equivalent of flat sawn, or plain sawn as pictured below.  Radial would be quarter sawn and rift sawn would be the grain running at about 45 degrees.  The quarter sawn (which is what we see in soundboard panels) would be the stiffest along the grain, the flat sawn the least stiff and, presumably, the rift sawn somewhere in the middle. 

So the question then is what is the grain orientation of the wood suppled for rib stock?  Seem to make sense that it should be rift sawn as that would mean no matter how you rotated the board along the longitudinal axis the modulus would not change.  I've sent a query to Christian Bolduc to find out what the grain orientation is of the stock that he sells and I'll let you know when I get an answer.  Obviously if the 1" by 1" rib stock is flat sawn then you will want to be aware of rotating that board before you cut it into a rib to be sure the grain orientation is how you want it, if one of those two options is even desirable.  I would be surprised if rib stock went out like that as that would create some uncertainty in the response depending on how the beam were rotated.  If it goes out rift sawn then rotation of the stock would make no difference as the grain orientation would remain the same. 

Obviously in my calculations I'm not taking into consideration varying grain orientations and varying MOE with the ribstock.  I'm assuming some consistency there.  If ribstock actually goes out with random grain orientation that certainly with skew the results and potentially create some problems for rebuilders.   If it doesn't then I'm not too worried about it.  

David,

Here is an excellent reference:  "Wood Handbook" by the US Forest Products Laboratory.  The pdf is ~14mB.
     https://www.fpl.fs.usda.gov/documnts/fplgtr/fplgtr113/fplgtr113.pdf
  
Check out Table 4-1; The first two columns are of interest.  Flat sawn v/s vertical grain differ (very roughly) by a factor of two.

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

So, Bolduc rib stock is all quarter sawn.  Of course you can convert it to flat sawn by rotating the board if you want to.  

The important part for this is that I'm using a consistent MOE in the analysis based on the species as I'm interested mostly in the relative performance between the ribs in an idealized situation. If interested in what that is let me know.  

OK thanks John. So tangential would be the equivalent of flat sawn, or plain sawn as pictured below.  Radial would be quarter sawn and rift sawn would be the grain running at about 45 degrees.  The quarter sawn (which is what we see in soundboard panels) would be the stiffest along the grain, the flat sawn the least stiff and, presumably, the rift sawn somewhere in the middle. 

So the question then is what is the grain orientation of the wood suppled for rib stock?  Seem to make sense that it should be rift sawn as that would mean no matter how you rotated the board along the longitudinal axis the modulus would not change.  I've sent a query to Christian Bolduc to find out what the grain orientation is of the stock that he sells and I'll let you know when I get an answer.  Obviously if the 1" by 1" rib stock is flat sawn then you will want to be aware of rotating that board before you cut it into a rib to be sure the grain orientation is how you want it, if one of those two options is even desirable.  I would be surprised if rib stock went out like that as that would create some uncertainty in the response depending on how the beam were rotated.  If it goes out rift sawn then rotation of the stock would make no difference as the grain orientation would remain the same. 

Obviously in my calculations I'm not taking into consideration varying grain orientations and varying MOE with the ribstock.  I'm assuming some consistency there.  If ribstock actually goes out with random grain orientation that certainly with skew the results and potentially create some problems for rebuilders.   If it doesn't then I'm not too worried about it.  

David,

Here is an excellent reference:  "Wood Handbook" by the US Forest Products Laboratory.  The pdf is ~14mB.
     https://www.fpl.fs.usda.gov/documnts/fplgtr/fplgtr113/fplgtr113.pdf
  
Check out Table 4-1; The first two columns are of interest.  Flat sawn v/s vertical grain differ (very roughly) by a factor of two.

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

For those interested here are some of the numbers I'm using.

When and if this is ever completed I will post the results like any study with a title page, abstract, Introduction, methods, results, discussion and references.  In the discussion will include a section on how actual outcomes may differ based on various factors.  Those will include things like scalloping, rib crowning, species and grain orientation, panel properties etc., and will also include some info on historical approaches to rib manufacturing, etc.  

So, Bolduc rib stock is all quarter sawn.  Of course you can convert it to flat sawn by rotating the board if you want to.  

The important part for this is that I'm using a consistent MOE in the analysis based on the species as I'm interested mostly in the relative performance between the ribs in an idealized situation. If interested in what that is let me know.  

OK thanks John. So tangential would be the equivalent of flat sawn, or plain sawn as pictured below.  Radial would be quarter sawn and rift sawn would be the grain running at about 45 degrees.  The quarter sawn (which is what we see in soundboard panels) would be the stiffest along the grain, the flat sawn the least stiff and, presumably, the rift sawn somewhere in the middle. 

So the question then is what is the grain orientation of the wood suppled for rib stock?  Seem to make sense that it should be rift sawn as that would mean no matter how you rotated the board along the longitudinal axis the modulus would not change.  I've sent a query to Christian Bolduc to find out what the grain orientation is of the stock that he sells and I'll let you know when I get an answer.  Obviously if the 1" by 1" rib stock is flat sawn then you will want to be aware of rotating that board before you cut it into a rib to be sure the grain orientation is how you want it, if one of those two options is even desirable.  I would be surprised if rib stock went out like that as that would create some uncertainty in the response depending on how the beam were rotated.  If it goes out rift sawn then rotation of the stock would make no difference as the grain orientation would remain the same. 

Obviously in my calculations I'm not taking into consideration varying grain orientations and varying MOE with the ribstock.  I'm assuming some consistency there.  If ribstock actually goes out with random grain orientation that certainly with skew the results and potentially create some problems for rebuilders.   If it doesn't then I'm not too worried about it.  

David,

Here is an excellent reference:  "Wood Handbook" by the US Forest Products Laboratory.  The pdf is ~14mB.
     https://www.fpl.fs.usda.gov/documnts/fplgtr/fplgtr113/fplgtr113.pdf
  
Check out Table 4-1; The first two columns are of interest.  Flat sawn v/s vertical grain differ (very roughly) by a factor of two.

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

What the poster doesn't seem to realize is that those textbook Modulus of Elasticity numbers are for the lumber trades not instrument making. A rib doesn't have the same exact function as a floor joist. One is a "spring" the other is not. Floor joists aren't scalloped and the MOE standard is at 12% moisture content. My firewood outside is about 12% moisture content. On the  large scale of lumber, the trade MOE is sufficient for engineers to use. But on the small scale of dried stock for pianos the lumber trade MOE is unreliable. 

The species itself when working with small pieces is quite variable in strength. I have had sugar pine in my hand that was stronger than spruce and some that were as light as Balsa wood. Also, for simplicity, think of scalloping as an MOE adjustment tool. Once you scallop, the textbook MOE goes out the window. The real craft is working with what is in your hand , not depending on formulas from textbooks, charts and spreadsheets. Those are for accolades.

In my real world testing of rib stock the deflection values could be altered just by scraping the scallop with a razor blade (microdust). Its very touchy, and to get both sides of the rib scallops to have the same deflection value is time consuming, but i find rewarding.

-chris

For those interested here are some of the numbers I'm using.

When and if this is ever completed I will post the results like any study with a title page, abstract, Introduction, methods, results, discussion and references.  In the discussion will include a section on how actual outcomes may differ based on various factors.  Those will include things like scalloping, rib crowning, species and grain orientation, panel properties etc., and will also include some info on historical approaches to rib manufacturing, etc.  

So, Bolduc rib stock is all quarter sawn.  Of course you can convert it to flat sawn by rotating the board if you want to.  

The important part for this is that I'm using a consistent MOE in the analysis based on the species as I'm interested mostly in the relative performance between the ribs in an idealized situation. If interested in what that is let me know.  

OK thanks John. So tangential would be the equivalent of flat sawn, or plain sawn as pictured below.  Radial would be quarter sawn and rift sawn would be the grain running at about 45 degrees.  The quarter sawn (which is what we see in soundboard panels) would be the stiffest along the grain, the flat sawn the least stiff and, presumably, the rift sawn somewhere in the middle. 

So the question then is what is the grain orientation of the wood suppled for rib stock?  Seem to make sense that it should be rift sawn as that would mean no matter how you rotated the board along the longitudinal axis the modulus would not change.  I've sent a query to Christian Bolduc to find out what the grain orientation is of the stock that he sells and I'll let you know when I get an answer.  Obviously if the 1" by 1" rib stock is flat sawn then you will want to be aware of rotating that board before you cut it into a rib to be sure the grain orientation is how you want it, if one of those two options is even desirable.  I would be surprised if rib stock went out like that as that would create some uncertainty in the response depending on how the beam were rotated.  If it goes out rift sawn then rotation of the stock would make no difference as the grain orientation would remain the same. 

Obviously in my calculations I'm not taking into consideration varying grain orientations and varying MOE with the ribstock.  I'm assuming some consistency there.  If ribstock actually goes out with random grain orientation that certainly with skew the results and potentially create some problems for rebuilders.   If it doesn't then I'm not too worried about it.  

David,

Here is an excellent reference:  "Wood Handbook" by the US Forest Products Laboratory.  The pdf is ~14mB.
     https://www.fpl.fs.usda.gov/documnts/fplgtr/fplgtr113/fplgtr113.pdf
  
Check out Table 4-1; The first two columns are of interest.  Flat sawn v/s vertical grain differ (very roughly) by a factor of two.

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

Both ribs and floor joists function as springs. They both flex under load and calculations about number and dimensions are both based on load bearing properties. Wood doesn't know what it will be used for when it is harvested  

EMC at glue up is not relevant. Ribs eventually function at EMC determined by the RH.  What's important is the consistent application of various criteria in the analysis.  

MOE indeed does vary with each piece of wood and that may ultimately affect what happens in the end. But that's not a reason not to compare designs  using objective criteria. It may be a reason not to draw 100% reliable conclusions about outcomes, andi fully understand that (but thanks for your continuous reminders).  However, it's not useless information. It's a starting point and useful in comparing design intention as well as a basis from which to make future tweaks or even wholesale changes. We agree that ultimately you, as Del used to say, have to shoot the designer and build the damn thing.  

Btw the word you were looking for is acolytes, not accolades 

I seriously question the veracity of your "microdust" claim as you've described it.  

This is a study of one particular aspect of piano design, the rib scale  I don't contend that it answers every question, but it might help answer one.  And, as I stated initially, since many techs are simply copying what's there, it offers a way to analyze just exactly what is there, how it might perform and/or whether the original execution was consistent with the design intention. All valuable. What one decides to do with the information is a separate question. It's not an end unto itself but I never claimed it was.  You have to build it at some point. To isolate variables you always need to keep all other things equal. In this case that means soundboard panel species, grain density and angle, crowning method, panel tapering, scalloping, downbearing settings, bridge structure and dimensions, even, perhaps, the hammer, ultimately.  In practice that's usually not the case.  

But research of any type always focuses on a single element.  It becomes one piece of the puzzle.  I believe there are objective criteria that can be used to guide and assess whatever that element is.  You seem to think everything is idiosyncratic or random  I don't agree.  

Why you object so strongly to this inquiry to the level of having engaged in ad hominem attacks makes me wonder what you're threatened by. I'm not attacking your choice of methods to use even when I find your reasoning flawed. That's up to you.  Though doth protest too much  

What the poster doesn't seem to realize is that those textbook Modulus of Elasticity numbers are for the lumber trades not instrument making. A rib doesn't have the same exact function as a floor joist. One is a "spring" the other is not. Floor joists aren't scalloped and the MOE standard is at 12% moisture content. My firewood outside is about 12% moisture content. On the  large scale of lumber, the trade MOE is sufficient for engineers to use. But on the small scale of dried stock for pianos the lumber trade MOE is unreliable. 

The species itself when working with small pieces is quite variable in strength. I have had sugar pine in my hand that was stronger than spruce and some that were as light as Balsa wood. Also, for simplicity, think of scalloping as an MOE adjustment tool. Once you scallop, the textbook MOE goes out the window. The real craft is working with what is in your hand , not depending on formulas from textbooks, charts and spreadsheets. Those are for accolades.

In my real world testing of rib stock the deflection values could be altered just by scraping the scallop with a razor blade (microdust). Its very touchy, and to get both sides of the rib scallops to have the same deflection value is time consuming, but i find rewarding.

-chris

For those interested here are some of the numbers I'm using.

When and if this is ever completed I will post the results like any study with a title page, abstract, Introduction, methods, results, discussion and references.  In the discussion will include a section on how actual outcomes may differ based on various factors.  Those will include things like scalloping, rib crowning, species and grain orientation, panel properties etc., and will also include some info on historical approaches to rib manufacturing, etc.  

So, Bolduc rib stock is all quarter sawn.  Of course you can convert it to flat sawn by rotating the board if you want to.  

The important part for this is that I'm using a consistent MOE in the analysis based on the species as I'm interested mostly in the relative performance between the ribs in an idealized situation. If interested in what that is let me know.  

OK thanks John. So tangential would be the equivalent of flat sawn, or plain sawn as pictured below.  Radial would be quarter sawn and rift sawn would be the grain running at about 45 degrees.  The quarter sawn (which is what we see in soundboard panels) would be the stiffest along the grain, the flat sawn the least stiff and, presumably, the rift sawn somewhere in the middle. 

So the question then is what is the grain orientation of the wood suppled for rib stock?  Seem to make sense that it should be rift sawn as that would mean no matter how you rotated the board along the longitudinal axis the modulus would not change.  I've sent a query to Christian Bolduc to find out what the grain orientation is of the stock that he sells and I'll let you know when I get an answer.  Obviously if the 1" by 1" rib stock is flat sawn then you will want to be aware of rotating that board before you cut it into a rib to be sure the grain orientation is how you want it, if one of those two options is even desirable.  I would be surprised if rib stock went out like that as that would create some uncertainty in the response depending on how the beam were rotated.  If it goes out rift sawn then rotation of the stock would make no difference as the grain orientation would remain the same. 

Obviously in my calculations I'm not taking into consideration varying grain orientations and varying MOE with the ribstock.  I'm assuming some consistency there.  If ribstock actually goes out with random grain orientation that certainly with skew the results and potentially create some problems for rebuilders.   If it doesn't then I'm not too worried about it.  

David,

Here is an excellent reference:  "Wood Handbook" by the US Forest Products Laboratory.  The pdf is ~14mB.
     https://www.fpl.fs.usda.gov/documnts/fplgtr/fplgtr113/fplgtr113.pdf
  
Check out Table 4-1; The first two columns are of interest.  Flat sawn v/s vertical grain differ (very roughly) by a factor of two.

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks

By the way chris since you've collected all this data on original rib scales, why don't you send some of it to me?  I could use it. 

Both ribs and floor joists function as springs. They both flex under load and calculations about number and dimensions are both based on load bearing properties. Wood doesn't know what it will be used for when it is harvested  

EMC at glue up is not relevant. Ribs eventually function at EMC determined by the RH.  What's important is the consistent application of various criteria in the analysis.  

MOE indeed does vary with each piece of wood and that may ultimately affect what happens in the end. But that's not a reason not to compare designs  using objective criteria. It may be a reason not to draw 100% reliable conclusions about outcomes, andi fully understand that (but thanks for your continuous reminders).  However, it's not useless information. It's a starting point and useful in comparing design intention as well as a basis from which to make future tweaks or even wholesale changes. We agree that ultimately you, as Del used to say, have to shoot the designer and build the damn thing.  

Btw the word you were looking for is acolytes, not accolades 

I seriously question the veracity of your "microdust" claim as you've described it.  

This is a study of one particular aspect of piano design, the rib scale  I don't contend that it answers every question, but it might help answer one.  And, as I stated initially, since many techs are simply copying what's there, it offers a way to analyze just exactly what is there, how it might perform and/or whether the original execution was consistent with the design intention. All valuable. What one decides to do with the information is a separate question. It's not an end unto itself but I never claimed it was.  You have to build it at some point. To isolate variables you always need to keep all other things equal. In this case that means soundboard panel species, grain density and angle, crowning method, panel tapering, scalloping, downbearing settings, bridge structure and dimensions, even, perhaps, the hammer, ultimately.  In practice that's usually not the case.  

But research of any type always focuses on a single element.  It becomes one piece of the puzzle.  I believe there are objective criteria that can be used to guide and assess whatever that element is.  You seem to think everything is idiosyncratic or random  I don't agree.  

Why you object so strongly to this inquiry to the level of having engaged in ad hominem attacks makes me wonder what you're threatened by. I'm not attacking your choice of methods to use even when I find your reasoning flawed. That's up to you.  Though doth protest too much  

What the poster doesn't seem to realize is that those textbook Modulus of Elasticity numbers are for the lumber trades not instrument making. A rib doesn't have the same exact function as a floor joist. One is a "spring" the other is not. Floor joists aren't scalloped and the MOE standard is at 12% moisture content. My firewood outside is about 12% moisture content. On the  large scale of lumber, the trade MOE is sufficient for engineers to use. But on the small scale of dried stock for pianos the lumber trade MOE is unreliable. 

The species itself when working with small pieces is quite variable in strength. I have had sugar pine in my hand that was stronger than spruce and some that were as light as Balsa wood. Also, for simplicity, think of scalloping as an MOE adjustment tool. Once you scallop, the textbook MOE goes out the window. The real craft is working with what is in your hand , not depending on formulas from textbooks, charts and spreadsheets. Those are for accolades.

In my real world testing of rib stock the deflection values could be altered just by scraping the scallop with a razor blade (microdust). Its very touchy, and to get both sides of the rib scallops to have the same deflection value is time consuming, but i find rewarding.

-chris

For those interested here are some of the numbers I'm using.

When and if this is ever completed I will post the results like any study with a title page, abstract, Introduction, methods, results, discussion and references.  In the discussion will include a section on how actual outcomes may differ based on various factors.  Those will include things like scalloping, rib crowning, species and grain orientation, panel properties etc., and will also include some info on historical approaches to rib manufacturing, etc.  

So, Bolduc rib stock is all quarter sawn.  Of course you can convert it to flat sawn by rotating the board if you want to.  

The important part for this is that I'm using a consistent MOE in the analysis based on the species as I'm interested mostly in the relative performance between the ribs in an idealized situation. If interested in what that is let me know.  

OK thanks John. So tangential would be the equivalent of flat sawn, or plain sawn as pictured below.  Radial would be quarter sawn and rift sawn would be the grain running at about 45 degrees.  The quarter sawn (which is what we see in soundboard panels) would be the stiffest along the grain, the flat sawn the least stiff and, presumably, the rift sawn somewhere in the middle. 

So the question then is what is the grain orientation of the wood suppled for rib stock?  Seem to make sense that it should be rift sawn as that would mean no matter how you rotated the board along the longitudinal axis the modulus would not change.  I've sent a query to Christian Bolduc to find out what the grain orientation is of the stock that he sells and I'll let you know when I get an answer.  Obviously if the 1" by 1" rib stock is flat sawn then you will want to be aware of rotating that board before you cut it into a rib to be sure the grain orientation is how you want it, if one of those two options is even desirable.  I would be surprised if rib stock went out like that as that would create some uncertainty in the response depending on how the beam were rotated.  If it goes out rift sawn then rotation of the stock would make no difference as the grain orientation would remain the same. 

Obviously in my calculations I'm not taking into consideration varying grain orientations and varying MOE with the ribstock.  I'm assuming some consistency there.  If ribstock actually goes out with random grain orientation that certainly with skew the results and potentially create some problems for rebuilders.   If it doesn't then I'm not too worried about it.  

David,

Here is an excellent reference:  "Wood Handbook" by the US Forest Products Laboratory.  The pdf is ~14mB.
     https://www.fpl.fs.usda.gov/documnts/fplgtr/fplgtr113/fplgtr113.pdf
  
Check out Table 4-1; The first two columns are of interest.  Flat sawn v/s vertical grain differ (very roughly) by a factor of two.

I'm collecting data for a rib scale study.  The attached PDF outlines one such analysis and the procedure.  If you are interested in participating by helping me collect data on projects you may have done, contact me privately and I'll give you the information that I need.  

This is a rudimentary analysis of a Steinway L rib scale along with a modifications to show how and why it might be improved, not redesigned, just optimized.  This is limited to the rib scale only.  Look it over if you are so inclined and let me know if you have questions or comments.  

Thanks