Pianotech

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

Won't open, David - protected view.  

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

Worked for me without a problem.

Won't open, David - protected view.  

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

This is very similar to the speadsheet I made up.  Except I don't measure the orginal FW.  For me, no need to measure twice.

I only want the 'change'.  When I measure the key, I'll zero out the scale.  Make modifications as needed so the scale will read the 'change' I'm looking for.

Thanks for sharing this.  

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

Yes it's true. You don't need the absolute number. But it's good to have it because it tells you where you are in terms of the front weight maximum. Since the front weight maximum is an indication of inertia indirectly, it's a good idea to know that number. 

In practice, I don't actually use the spreadsheet when I'm doing it this way, I just do it in my head as I'm going, so I'm actually only weighing the front weight once and modifying that based on my original balance weight measurement compared to my target balance weight. I put up the spreadsheet for those who are wondering how these numbers are derived and to illustrate the one-to-one relationship between front weight and balance weight

By the way, speaking of front weight maximums, you can use a version of this sheet to determine your strike weights by pre-setting the front weight at the level that you want say 80% of front weight maximum and then by sample determine what strike weight goes with that front weight to achieve your balance weight. Do that for several samples through the scale and you can use that to establish your strike weight curve either using Stanwood's chart or calculating it. That was the basic idea of the spreadsheet. I posted a month or two ago  

This is very similar to the speadsheet I made up.  Except I don't measure the orginal FW.  For me, no need to measure twice.

I only want the 'change'.  When I measure the key, I'll zero out the scale.  Make modifications as needed so the scale will read the 'change' I'm looking for.

Thanks for sharing this.  

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

I've modified the sheet and attached it here to include a simple way to self-generate your own SW curve based on FW targets that will fit the AR that that you have in the system.  If you know how to chart and calculate trendline curves (I've posted that before) you can do it that way too.  Or, you can use the SW sample data to generate the basic architecture for using the Stanwood paper chart to plot, or you can simply extrapolate on your own freestyle.  Any of those methods will work to get you into the area of SWs that you'll need to get to the next step of adjusting the FWs to hit your BW target with optimized FWs and the proper inertia levels that go along with that formula.

I've included suggestions as to how to hit the sweet spot of inertia using this simple method.  Again, pretty self-explanatory.  Nothing is locked in this sheet, you can alter at will (or by accident) so I'd save a master in case you screw it up.  There's also a simple AR calculator there with instructions for those obsessed with knowing what the AR is (I'm not).

Any questions post here or privately.  Don't really want to get into a clown show though.  Hopefully some of you will find it useful.

If you have trouble opening it, ask your nearest high school or college student.

Yes it's true. You don't need the absolute number. But it's good to have it because it tells you where you are in terms of the front weight maximum. Since the front weight maximum is an indication of inertia indirectly, it's a good idea to know that number. 

In practice, I don't actually use the spreadsheet when I'm doing it this way, I just do it in my head as I'm going, so I'm actually only weighing the front weight once and modifying that based on my original balance weight measurement compared to my target balance weight. I put up the spreadsheet for those who are wondering how these numbers are derived and to illustrate the one-to-one relationship between front weight and balance weight

By the way, speaking of front weight maximums, you can use a version of this sheet to determine your strike weights by pre-setting the front weight at the level that you want say 80% of front weight maximum and then by sample determine what strike weight goes with that front weight to achieve your balance weight. Do that for several samples through the scale and you can use that to establish your strike weight curve either using Stanwood's chart or calculating it. That was the basic idea of the spreadsheet. I posted a month or two ago  

This is very similar to the speadsheet I made up.  Except I don't measure the orginal FW.  For me, no need to measure twice.

I only want the 'change'.  When I measure the key, I'll zero out the scale.  Make modifications as needed so the scale will read the 'change' I'm looking for.

Thanks for sharing this.  

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

I've modified the sheet and attached it here to include a simple way to self-generate your own SW curve based on FW targets that will fit the AR that that you have in the system.  If you know how to chart and calculate trendline curves (I've posted that before) you can do it that way too.  Or, you can use the SW sample data to generate the basic architecture for using the Stanwood paper chart to plot, or you can simply extrapolate on your own freestyle.  Any of those methods will work to get you into the area of SWs that you'll need to get to the next step of adjusting the FWs to hit your BW target with optimized FWs and the proper inertia levels that go along with that formula.

I've included suggestions as to how to hit the sweet spot of inertia using this simple method.  Again, pretty self-explanatory.  Nothing is locked in this sheet, you can alter at will (or by accident) so I'd save a master in case you screw it up.  There's also a simple AR calculator there with instructions for those obsessed with knowing what the AR is (I'm not).

Any questions post here or privately.  Don't really want to get into a clown show though.  Hopefully some of you will find it useful.

If you have trouble opening it, ask your nearest high school or college student.

Yes it's true. You don't need the absolute number. But it's good to have it because it tells you where you are in terms of the front weight maximum. Since the front weight maximum is an indication of inertia indirectly, it's a good idea to know that number. 

In practice, I don't actually use the spreadsheet when I'm doing it this way, I just do it in my head as I'm going, so I'm actually only weighing the front weight once and modifying that based on my original balance weight measurement compared to my target balance weight. I put up the spreadsheet for those who are wondering how these numbers are derived and to illustrate the one-to-one relationship between front weight and balance weight

By the way, speaking of front weight maximums, you can use a version of this sheet to determine your strike weights by pre-setting the front weight at the level that you want say 80% of front weight maximum and then by sample determine what strike weight goes with that front weight to achieve your balance weight. Do that for several samples through the scale and you can use that to establish your strike weight curve either using Stanwood's chart or calculating it. That was the basic idea of the spreadsheet. I posted a month or two ago  

This is very similar to the speadsheet I made up.  Except I don't measure the orginal FW.  For me, no need to measure twice.

I only want the 'change'.  When I measure the key, I'll zero out the scale.  Make modifications as needed so the scale will read the 'change' I'm looking for.

Thanks for sharing this.  

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

I don't want to get too into this, clearly I've taken up residence, rent free, in somebody's head. But a couple of comments. First, a spreadsheet can be a very helpful visual aid and I hope people will get some benefit. If they aren't interested then they don't have to use it. I'm just offering it as a free tool. Second, the claim was that Stanwood doesn't measure inertia. While it's true that none of the data points in the Stanwood system are actual measures of inertia, make no mistake, matching strike weight ratios to strike weight curves is designed to control levels of inertia since it's that relationship that is the biggest driving force for inertia in the piano action. Many other people who are producing touch design spreadsheet, like Nick Gravagne or Fandrich and Rhodes have as their goal the same relationship. Actual inertia data is probably not that useful to us since ultimately,  in assembling an action,  we're dealing with weight and distance. Third, as far as voicing diagrams, being of any use, the industry is replete with voicing diagrams whether that's Yamaha, Renner or traditional as historical literature on the subject. While it's no substitute for experience they can provide a foundation for which parts of the hammer we might want to be paying attention to to accomplish certain tonal goals. The other comments in that reply, I won't dignify by responding to. 

I've modified the sheet and attached it here to include a simple way to self-generate your own SW curve based on FW targets that will fit the AR that that you have in the system.  If you know how to chart and calculate trendline curves (I've posted that before) you can do it that way too.  Or, you can use the SW sample data to generate the basic architecture for using the Stanwood paper chart to plot, or you can simply extrapolate on your own freestyle.  Any of those methods will work to get you into the area of SWs that you'll need to get to the next step of adjusting the FWs to hit your BW target with optimized FWs and the proper inertia levels that go along with that formula.

I've included suggestions as to how to hit the sweet spot of inertia using this simple method.  Again, pretty self-explanatory.  Nothing is locked in this sheet, you can alter at will (or by accident) so I'd save a master in case you screw it up.  There's also a simple AR calculator there with instructions for those obsessed with knowing what the AR is (I'm not).

Any questions post here or privately.  Don't really want to get into a clown show though.  Hopefully some of you will find it useful.

If you have trouble opening it, ask your nearest high school or college student.

Yes it's true. You don't need the absolute number. But it's good to have it because it tells you where you are in terms of the front weight maximum. Since the front weight maximum is an indication of inertia indirectly, it's a good idea to know that number. 

In practice, I don't actually use the spreadsheet when I'm doing it this way, I just do it in my head as I'm going, so I'm actually only weighing the front weight once and modifying that based on my original balance weight measurement compared to my target balance weight. I put up the spreadsheet for those who are wondering how these numbers are derived and to illustrate the one-to-one relationship between front weight and balance weight

By the way, speaking of front weight maximums, you can use a version of this sheet to determine your strike weights by pre-setting the front weight at the level that you want say 80% of front weight maximum and then by sample determine what strike weight goes with that front weight to achieve your balance weight. Do that for several samples through the scale and you can use that to establish your strike weight curve either using Stanwood's chart or calculating it. That was the basic idea of the spreadsheet. I posted a month or two ago  

This is very similar to the speadsheet I made up.  Except I don't measure the orginal FW.  For me, no need to measure twice.

I only want the 'change'.  When I measure the key, I'll zero out the scale.  Make modifications as needed so the scale will read the 'change' I'm looking for.

Thanks for sharing this.  

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

Is everything I'm trying to post here now being blocked?

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-10-2025 12:52
From: David Love
Subject: FW Spreadsheet for Renner KMD

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
------------------------------

Before this I posted a request for somebody to please send me the post that was deleted, a copy of the text, because I didn't save it and I would like to have it. I use these posts as a reference and for further explanation  when called upon for it. I thought it was a legitimate explanation of the process of using front weight as a determinant of inertia. If somebody finds that offensive, or can't handle a harmless cartoon, well, to put it perhaps in more familiar Melania speak, "I don't really care, do you?" 

So admin police, please send me a copy of it and, after that, you can delete this entire thread, the spreadsheets and anything else of mine you want. This is ridiculous. Some horse's ass starts impugning my work on this thread, name calling in a manner which is inconsistent with the so-called bylaws governing professional conduct, whatever they're worth, and my post get taken down because I challenge someone's ad hominem attacks and ill informed and self serving attempt at science???  Send me the text of the post please and good riddance. 

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-15-2025 15:55
From: David Love
Subject: FW Spreadsheet for Renner KMD

Is everything I'm trying to post here now being blocked?

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-10-2025 12:52
From: David Love
Subject: FW Spreadsheet for Renner KMD

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
------------------------------

Come on man, seriously? How can you work on pianos and not be able to connect the dots here?  David I tend to agree with your political ideas AND I still can't understand why you can't freaking resist the urge of leaving your political beliefs to yourself (you know - like pretty much the whole entire rest of the forum?).

You are on a piano forum; for pianos.  You have the freedom to start your own piano forum where you could have a mandatory rule where each post must contain a brilliant political comment somewhere towards the beginning or end of each post.  

But why stop there? Might as well add a comment for your religious beliefs, your sexual orientation, and your race, and what food you choose to eat too.  ALL of these important beliefs definitely deserve a place here too!  We should make a motion to require and mention this in every single post we make from here on out.

I vote yes, cause it sounds VERY fun!

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 16:35
From: David Love
Subject: FW Spreadsheet for Renner KMD

Before this I posted a request for somebody to please send me the post that was deleted, a copy of the text, because I didn't save it and I would like to have it. I use these posts as a reference and for further explanation  when called upon for it. I thought it was a legitimate explanation of the process of using front weight as a determinant of inertia. If somebody finds that offensive, or can't handle a harmless cartoon, well, to put it perhaps in more familiar Melania speak, "I don't really care, do you?" 

So admin police, please send me a copy of it and, after that, you can delete this entire thread, the spreadsheets and anything else of mine you want. This is ridiculous. Some horse's ass starts impugning my work on this thread, name calling in a manner which is inconsistent with the so-called bylaws governing professional conduct, whatever they're worth, and my post get taken down because I challenge someone's ad hominem attacks and ill informed and self serving attempt at science???  Send me the text of the post please and good riddance. 

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-15-2025 15:55
From: David Love
Subject: FW Spreadsheet for Renner KMD

Is everything I'm trying to post here now being blocked?

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-10-2025 12:52
From: David Love
Subject: FW Spreadsheet for Renner KMD

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
------------------------------

Mathew, are you aware that your website is in violation of the PTG Graphic Standards manual?

Come on man, seriously? How can you work on pianos and not be able to connect the dots here?  David I tend to agree with your political ideas AND I still can't understand why you can't freaking resist the urge of leaving your political beliefs to yourself (you know - like pretty much the whole entire rest of the forum?).

You are on a piano forum; for pianos.  You have the freedom to start your own piano forum where you could have a mandatory rule where each post must contain a brilliant political comment somewhere towards the beginning or end of each post.  

But why stop there? Might as well add a comment for your religious beliefs, your sexual orientation, and your race, and what food you choose to eat too.  ALL of these important beliefs definitely deserve a place here too!  We should make a motion to require and mention this in every single post we make from here on out.

I vote yes, cause it sounds VERY fun!

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 16:35
From: David Love
Subject: FW Spreadsheet for Renner KMD

Before this I posted a request for somebody to please send me the post that was deleted, a copy of the text, because I didn't save it and I would like to have it. I use these posts as a reference and for further explanation  when called upon for it. I thought it was a legitimate explanation of the process of using front weight as a determinant of inertia. If somebody finds that offensive, or can't handle a harmless cartoon, well, to put it perhaps in more familiar Melania speak, "I don't really care, do you?" 

So admin police, please send me a copy of it and, after that, you can delete this entire thread, the spreadsheets and anything else of mine you want. This is ridiculous. Some horse's ass starts impugning my work on this thread, name calling in a manner which is inconsistent with the so-called bylaws governing professional conduct, whatever they're worth, and my post get taken down because I challenge someone's ad hominem attacks and ill informed and self serving attempt at science???  Send me the text of the post please and good riddance. 

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-15-2025 15:55
From: David Love
Subject: FW Spreadsheet for Renner KMD

Is everything I'm trying to post here now being blocked?

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-10-2025 12:52
From: David Love
Subject: FW Spreadsheet for Renner KMD

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
------------------------------

Is everything I'm trying to post here now being blocked?

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

I said I liked your cartoon.  That got disappeared.  The mind police are at it again.

------------------------------
William Truitt RPT
Bridgewater NH
(603) 744-2277

Original Message:
Sent: 06-15-2025 15:55
From: David Love
Subject: FW Spreadsheet for Renner KMD

Is everything I'm trying to post here now being blocked?

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-10-2025 12:52
From: David Love
Subject: FW Spreadsheet for Renner KMD

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
------------------------------

The cartoon was kind of funny, BUT why post your personal stuff here??? And then when it disappears you get all super sensitive about it. 

And no - I did not flag your cartoon, David. I think it's more practical to assume the moderators are doing their job of deleting useless posts only meant to divide the masses and keep us distracted from actual important stuff. 

But I do not  think it is too hard to see why some posts stay and others not so much.   You asked the question so, so I'm just taking a stab at it is all.  🎹🎹

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 20:20
From: William Truitt
Subject: FW Spreadsheet for Renner KMD

I said I liked your cartoon.  That got disappeared.  The mind police are at it again.

------------------------------
William Truitt RPT
Bridgewater NH
(603) 744-2277

Original Message:
Sent: 06-15-2025 15:55
From: David Love
Subject: FW Spreadsheet for Renner KMD

Is everything I'm trying to post here now being blocked?

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-10-2025 12:52
From: David Love
Subject: FW Spreadsheet for Renner KMD

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
------------------------------

I think you're beating a dead horse.  I'm done with this discussion.  But if I'm going to tolerate people taking pot shots at me personally, then you and  others can tolerate my ostracism cartoon, even if you are homeless.  I don't need any lectures. My contributions to this list over several decades speak for themselves. I'd rate that I post anything controversial but I do call people on their bullshit.  During Covid people were posting bogus health claims that might have killed people. No objections there. Weird standards we have. 

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-15-2025 21:09
From: Matthew Walworth
Subject: FW Spreadsheet for Renner KMD

The cartoon was kind of funny, BUT why post your personal stuff here??? And then when it disappears you get all super sensitive about it. 

And no - I did not flag your cartoon, David. I think it's more practical to assume the moderators are doing their job of deleting useless posts only meant to divide the masses and keep us distracted from actual important stuff. 

But I do not  think it is too hard to see why some posts stay and others not so much.   You asked the question so, so I'm just taking a stab at it is all.  🎹🎹

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 20:20
From: William Truitt
Subject: FW Spreadsheet for Renner KMD

I said I liked your cartoon.  That got disappeared.  The mind police are at it again.

------------------------------
William Truitt RPT
Bridgewater NH
(603) 744-2277

Original Message:
Sent: 06-15-2025 15:55
From: David Love
Subject: FW Spreadsheet for Renner KMD

Is everything I'm trying to post here now being blocked?

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-10-2025 12:52
From: David Love
Subject: FW Spreadsheet for Renner KMD

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
------------------------------

I have in no way fired any shots at you. Just being fairly straight forward and to the point and honest, because it seems you didn't understand why they took your Post down. No horse beating from me.  It seemed Iike you wanted help to figure out why your off topic posts were removed.  I reply with a quite straight forward observation and now you think I am attacking you?  When I asked if you were serious - I was serious; because I can't tell if you're just bored and trolling. Because that's the only thing I can come up with.

Very strangely different perspectives we are taking from this. I agree on pretty much everything you post FYI, but no - I am not attacking you.  You are the one throwing the "snowfkake" term around and ECT after all making attacks right and left.  I'm sure this post will sound like an attack to you?  I suppose anything could be read however you like.  Words are fun aren't they?

 I have zero personal issues with you, I assure you. But it does seem you might have one with me. Just an observation based on your last comment. I'm not the one who stirred up the dust around here to begin with anyway, I just happened to randomly stroll into an already dusty room and am only here to say "hey guys, it's really dusty in here". 

🎹🎹🎹🎶🎶🎶

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 21:54
From: David Love
Subject: FW Spreadsheet for Renner KMD

I think you're beating a dead horse.  I'm done with this discussion.  But if I'm going to tolerate people taking pot shots at me personally, then you and  others can tolerate my ostracism cartoon, even if you are homeless.  I don't need any lectures. My contributions to this list over several decades speak for themselves. I'd rate that I post anything controversial but I do call people on their bullshit.  During Covid people were posting bogus health claims that might have killed people. No objections there. Weird standards we have. 

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-15-2025 21:09
From: Matthew Walworth
Subject: FW Spreadsheet for Renner KMD

The cartoon was kind of funny, BUT why post your personal stuff here??? And then when it disappears you get all super sensitive about it. 

And no - I did not flag your cartoon, David. I think it's more practical to assume the moderators are doing their job of deleting useless posts only meant to divide the masses and keep us distracted from actual important stuff. 

But I do not  think it is too hard to see why some posts stay and others not so much.   You asked the question so, so I'm just taking a stab at it is all.  🎹🎹

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 20:20
From: William Truitt
Subject: FW Spreadsheet for Renner KMD

I said I liked your cartoon.  That got disappeared.  The mind police are at it again.

------------------------------
William Truitt RPT
Bridgewater NH
(603) 744-2277

Original Message:
Sent: 06-15-2025 15:55
From: David Love
Subject: FW Spreadsheet for Renner KMD

Is everything I'm trying to post here now being blocked?

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-10-2025 12:52
From: David Love
Subject: FW Spreadsheet for Renner KMD

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
------------------------------

Thanks for the offer, I wasn't born yesterday and don't require explanations  I understand why it was taken down. I just don't agree with the system or the criteria. I see a lot more offensive stuff that is given a pass.  Put it to bed Matthew. You're not the arbiter here. 

I have in no way fired any shots at you. Just being fairly straight forward and to the point and honest, because it seems you didn't understand why they took your Post down. No horse beating from me.  It seemed Iike you wanted help to figure out why your off topic posts were removed.  I reply with a quite straight forward observation and now you think I am attacking you?  When I asked if you were serious - I was serious; because I can't tell if you're just bored and trolling. Because that's the only thing I can come up with.

Very strangely different perspectives we are taking from this. I agree on pretty much everything you post FYI, but no - I am not attacking you.  You are the one throwing the "snowfkake" term around and ECT after all making attacks right and left.  I'm sure this post will sound like an attack to you?  I suppose anything could be read however you like.  Words are fun aren't they?

 I have zero personal issues with you, I assure you. But it does seem you might have one with me. Just an observation based on your last comment. I'm not the one who stirred up the dust around here to begin with anyway, I just happened to randomly stroll into an already dusty room and am only here to say "hey guys, it's really dusty in here". 

🎹🎹🎹🎶🎶🎶

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 21:54
From: David Love
Subject: FW Spreadsheet for Renner KMD

I think you're beating a dead horse.  I'm done with this discussion.  But if I'm going to tolerate people taking pot shots at me personally, then you and  others can tolerate my ostracism cartoon, even if you are homeless.  I don't need any lectures. My contributions to this list over several decades speak for themselves. I'd rate that I post anything controversial but I do call people on their bullshit.  During Covid people were posting bogus health claims that might have killed people. No objections there. Weird standards we have. 

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-15-2025 21:09
From: Matthew Walworth
Subject: FW Spreadsheet for Renner KMD

The cartoon was kind of funny, BUT why post your personal stuff here??? And then when it disappears you get all super sensitive about it. 

And no - I did not flag your cartoon, David. I think it's more practical to assume the moderators are doing their job of deleting useless posts only meant to divide the masses and keep us distracted from actual important stuff. 

But I do not  think it is too hard to see why some posts stay and others not so much.   You asked the question so, so I'm just taking a stab at it is all.  🎹🎹

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 20:20
From: William Truitt
Subject: FW Spreadsheet for Renner KMD

I said I liked your cartoon.  That got disappeared.  The mind police are at it again.

------------------------------
William Truitt RPT
Bridgewater NH
(603) 744-2277

Original Message:
Sent: 06-15-2025 15:55
From: David Love
Subject: FW Spreadsheet for Renner KMD

Is everything I'm trying to post here now being blocked?

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-10-2025 12:52
From: David Love
Subject: FW Spreadsheet for Renner KMD

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
------------------------------

There are no arbiters here - this is the wild wild west, but I appreciate it Sir.

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 22:38
From: David Love
Subject: FW Spreadsheet for Renner KMD

Thanks for the offer, I wasn't born yesterday and don't require explanations  I understand why it was taken down. I just don't agree with the system or the criteria. I see a lot more offensive stuff that is given a pass.  Put it to bed Matthew. You're not the arbiter here. 

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-15-2025 22:14
From: Matthew Walworth
Subject: FW Spreadsheet for Renner KMD

I have in no way fired any shots at you. Just being fairly straight forward and to the point and honest, because it seems you didn't understand why they took your Post down. No horse beating from me.  It seemed Iike you wanted help to figure out why your off topic posts were removed.  I reply with a quite straight forward observation and now you think I am attacking you?  When I asked if you were serious - I was serious; because I can't tell if you're just bored and trolling. Because that's the only thing I can come up with.

Very strangely different perspectives we are taking from this. I agree on pretty much everything you post FYI, but no - I am not attacking you.  You are the one throwing the "snowfkake" term around and ECT after all making attacks right and left.  I'm sure this post will sound like an attack to you?  I suppose anything could be read however you like.  Words are fun aren't they?

 I have zero personal issues with you, I assure you. But it does seem you might have one with me. Just an observation based on your last comment. I'm not the one who stirred up the dust around here to begin with anyway, I just happened to randomly stroll into an already dusty room and am only here to say "hey guys, it's really dusty in here". 

🎹🎹🎹🎶🎶🎶

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 21:54
From: David Love
Subject: FW Spreadsheet for Renner KMD

I think you're beating a dead horse.  I'm done with this discussion.  But if I'm going to tolerate people taking pot shots at me personally, then you and  others can tolerate my ostracism cartoon, even if you are homeless.  I don't need any lectures. My contributions to this list over several decades speak for themselves. I'd rate that I post anything controversial but I do call people on their bullshit.  During Covid people were posting bogus health claims that might have killed people. No objections there. Weird standards we have. 

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-15-2025 21:09
From: Matthew Walworth
Subject: FW Spreadsheet for Renner KMD

The cartoon was kind of funny, BUT why post your personal stuff here??? And then when it disappears you get all super sensitive about it. 

And no - I did not flag your cartoon, David. I think it's more practical to assume the moderators are doing their job of deleting useless posts only meant to divide the masses and keep us distracted from actual important stuff. 

But I do not  think it is too hard to see why some posts stay and others not so much.   You asked the question so, so I'm just taking a stab at it is all.  🎹🎹

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 20:20
From: William Truitt
Subject: FW Spreadsheet for Renner KMD

I said I liked your cartoon.  That got disappeared.  The mind police are at it again.

------------------------------
William Truitt RPT
Bridgewater NH
(603) 744-2277

Original Message:
Sent: 06-15-2025 15:55
From: David Love
Subject: FW Spreadsheet for Renner KMD

Is everything I'm trying to post here now being blocked?

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-10-2025 12:52
From: David Love
Subject: FW Spreadsheet for Renner KMD

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
------------------------------

Matthew, you're making this about you. It has nothing to do with you other than your unwanted "come on man" lectures. 

My issue is with the one obnoxious individual who responds to my posts or questions about his "reasoning" with ad hominem attacks and a moderator who lets things slide that I find offensive or even dangerous and singles out a harmless, though admittedly meant to tweak, cartoon of mine to remove a much larger explanatory post, and the criteria that allows the tyranny of one to take something down. Capiche?  You act like this is some sort of sacred ground. Spoiler alert, there's a lot of crap posted here, bad science, mythology, and self serving and shameless promotion. But there is some good information too.

I originally made this post in earnest to offer a free spreadsheet tool for those interested and then offered an explanation (now removed) for why this works. No good deed goes unpunished, I guess. But when people misstate my postings in order to construct a straw man argument and use that to attack me, impugn my work or my contributions, I don't take kindly to it and call it for what it is and who they are. I offer no apologies for that.  Your admonitions are neither needed nor welcome. I know exactly what I'm doing.  I've been in this Forum since before you were even a twinkle in your mother's eye. 

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-15-2025 22:45
From: Matthew Walworth
Subject: FW Spreadsheet for Renner KMD

There are no arbiters here - this is the wild wild west, but I appreciate it Sir.

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 22:38
From: David Love
Subject: FW Spreadsheet for Renner KMD

Thanks for the offer, I wasn't born yesterday and don't require explanations  I understand why it was taken down. I just don't agree with the system or the criteria. I see a lot more offensive stuff that is given a pass.  Put it to bed Matthew. You're not the arbiter here. 

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-15-2025 22:14
From: Matthew Walworth
Subject: FW Spreadsheet for Renner KMD

I have in no way fired any shots at you. Just being fairly straight forward and to the point and honest, because it seems you didn't understand why they took your Post down. No horse beating from me.  It seemed Iike you wanted help to figure out why your off topic posts were removed.  I reply with a quite straight forward observation and now you think I am attacking you?  When I asked if you were serious - I was serious; because I can't tell if you're just bored and trolling. Because that's the only thing I can come up with.

Very strangely different perspectives we are taking from this. I agree on pretty much everything you post FYI, but no - I am not attacking you.  You are the one throwing the "snowfkake" term around and ECT after all making attacks right and left.  I'm sure this post will sound like an attack to you?  I suppose anything could be read however you like.  Words are fun aren't they?

 I have zero personal issues with you, I assure you. But it does seem you might have one with me. Just an observation based on your last comment. I'm not the one who stirred up the dust around here to begin with anyway, I just happened to randomly stroll into an already dusty room and am only here to say "hey guys, it's really dusty in here". 

🎹🎹🎹🎶🎶🎶

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 21:54
From: David Love
Subject: FW Spreadsheet for Renner KMD

I think you're beating a dead horse.  I'm done with this discussion.  But if I'm going to tolerate people taking pot shots at me personally, then you and  others can tolerate my ostracism cartoon, even if you are homeless.  I don't need any lectures. My contributions to this list over several decades speak for themselves. I'd rate that I post anything controversial but I do call people on their bullshit.  During Covid people were posting bogus health claims that might have killed people. No objections there. Weird standards we have. 

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-15-2025 21:09
From: Matthew Walworth
Subject: FW Spreadsheet for Renner KMD

The cartoon was kind of funny, BUT why post your personal stuff here??? And then when it disappears you get all super sensitive about it. 

And no - I did not flag your cartoon, David. I think it's more practical to assume the moderators are doing their job of deleting useless posts only meant to divide the masses and keep us distracted from actual important stuff. 

But I do not  think it is too hard to see why some posts stay and others not so much.   You asked the question so, so I'm just taking a stab at it is all.  🎹🎹

------------------------------
Matthew Walworth
A.M.O. Pianos
Lebanon, TN 37087

Original Message:
Sent: 06-15-2025 20:20
From: William Truitt
Subject: FW Spreadsheet for Renner KMD

I said I liked your cartoon.  That got disappeared.  The mind police are at it again.

------------------------------
William Truitt RPT
Bridgewater NH
(603) 744-2277

Original Message:
Sent: 06-15-2025 15:55
From: David Love
Subject: FW Spreadsheet for Renner KMD

Is everything I'm trying to post here now being blocked?

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-10-2025 12:52
From: David Love
Subject: FW Spreadsheet for Renner KMD

For those using the Renner KMD device to rebalance actions (or even if you're doing it the old way), here's a spreadsheet that you can use (see attachment).  Instructions on the sheet, pretty self explanatory.  

------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
------------------------------

Fw gives you a false read. And because it does, the entire current system of measurement is incorrect. One may think they are getting a controlled and even inertia but its the opposite. Fw does not tell you the correct amount of lead to put in the key or where to put it. You can use infinite number of combinations of grams, # of leads, and locations that will get the same static key to move. The only reason its been accepted for so long is because its probably in a little better shape than before it was worked on. Ususally fixing friction alone fixes that.  Whats being missed is that when inertia is addressed properly, then there is a smoothness that is attained across the keyboard that gives a pianist something they dont have to think about. Like when aftertouch is not even. 

-chris

------------------------------
Chernobieff Piano Restorations

Inertia Touch Wave(ITW) The most advanced silky smooth actions.

Engineered Hygroscopic Soundboards. The strongest and lightest boards made today for acoustic projection, richness and warmth.

865-986-7720 (text only please)

I am reposting this response without the cartoon as the moderator suggested would be done.  I tried to send a message to that effect to the "contact us" link as instructed, which, of course, doesn't work.  Why am I not surprised.  If you feel the need to remove this for some reason, please advise me in advance.  

It might be noted that the moderator claims to have sent me an offer to repost if the cartoon were removed.  Never received.  You might look into that.  A better system of option to edit before just unannounced censoring would be preferable, in my opinion.  

Not looking for further discussion here.  The post and its intention speaks for itself and the offer of the spread sheets for general use, if desired, was genuine with no strings attached.

This reply explains why the FW is not a "false read" as claimed but a reliable indicator, if used properly with other variables, of how to achieve desired levels of inertia and the proper combination of SW and AR that leads to that.  In the various methods cited, all roads lead to Rome, as it were.  This is one simple method of getting there.  I won't comment here further on the references to friction or aftertouch that were part of that post because they are irrelevant in this discussion. There are other non sequiturs in there as well, for example; "the reason its (sic) been accepted for so long..." which I might comment on if I could fathom what was meant.  The post to which I was replying is copied at the bottom for context.  I'm waiting for someone to say "but mass is not the same as weight".  No, it isn't.  But as long as we're talking about balancing actions here on earth, the two terms are interchangeable--I wanted to get ahead of that.  If you ship off to the Moon or Mars, of course, you will have to reconsider.  And Godspeed.  

--------------------------------------------------------------------------------------------------------------------- 

Subject: RE: FW Spreadsheet for Renner KMD

That's incorrect.  The FW required to achieve a targeted BW is directly proportional to the relationship between the AR and the SW and that relationship is the main driver of inertia.  Key lead location is a separate matter, not inconsequential but not that significant in this part of the discussion.  

If you have an AR of 6.0 and a SW that for a BW of 37 grams requires a FW of 32 grams, that AR:SW relationship will yield some specific level of inertia primarily driven by the AR:SW relationship with a smaller contribution by the key and the leads and virtually no contribution by the wippen (see Gravagne's, Voit's or Rhodes' comments on that subject for reference.)

Now, if you increase the SW in that system by 1 gram with the same target of 37g balance weight, you will require a FW of + 6 grams to achieve that.  An AR of 6.0 means a change in the SW of 1 gram yields a change of 6 grams at the key and will require adding 6 grams of FW to offset that.  Basic concept.  The inertia will necessarily be higher in this iteration because the mass being accelerated by the same AR is higher (not to mention a small but measurable increase in the inertia because of the added lead).  That change is reflected in the FW required to achieve the requisite BW and is always proportional to the change in inertia.

Let me restate; changes in inertia will always be proportional to the FW change if the two other variables are held constant, in our case the BW and the AR.  

So in the Stanwood system, he has determined, by outlining the FW maximum, when you are crossing that FW ceiling that is an indication that the AR:SW relationship is not advantageous.

Obviously, there are some ways to confound those conclusions if you don't hold the BW and AR constant.  But you are then comparing apples to oranges.  Only if the BW and AR remain constant can you compare the two AR:SW relationships and interpret that through the FW levels AND those levels are note specific with higher ceilings in the bass and lower ceilings in the treble (see my spreadsheet for clarification).  

In the "Actions to Die For" method put forth by Fandrich and Rhodes, the ITF number they derive is based on this relationship (primarily) because that's the main driver of inertia.  In the Gravagne system the conclusion he draws about ideal hammer weight based on measuring the levers takes into account the same relationship.  In the Stanwood system the same principle applies.  

My simplified system for determining proper levels of inertia and the correct AR:SW relationship starts with a presetting a FW target of about 80-85% of FW maximum as outlined by Stanwood (though my numbers differ just slightly).  For me, and by my analysis and discussions with both Gravagne and Rhodes, that is the sweet spot.  By presetting the FW and finding the SW that yields a normal BW of 36 - 38 grams you will guarantee an AR:SW relationship that produces an action with inertia in the desired zone, an action to die for, or whatever moniker you wish to assign.  It works, and it works every time.  

What happens when you wander outside of that target by, for example, choosing a BW target of 42 grams or of 32 grams?  That's for another discussion but if you think about it long enough you will see that FW must be considered along with the target BW.  Those two variables alone, however, will tell you a lot in assessing an action.  For example, let's say you have an action that has a BW of 45 grams and a FW that is already 100% of maximum or simply has a lot of lead to suspicious levels.  To bring that action down to a compliant BW in this system you would have to further exceed the 100% value by another 8 grams or so and that would be an indication that you have to alter the AR to make it work properly, at least in terms of controlling inertia. 

Similarly, if you have an action that weighs off at 32 grams BW and the FWs are low, around 70% of maximum then you can assume, correctly, that removing yet more lead to raise the BW will put that action below a minimum threshold of FW (we haven't really talked about that but there is a floor as well as a ceiling).  In that case, the inertia will be predictably very low, too low in fact.  Actions where the inertia is too low don't give adequate feedback to the player, especially high level players.  So don't get too hung up on low inertia or that lower must be better.  There is a point of diminishing returns.

But this is an easy way to quickly assess an action by just measuring the BW and seeing what the lead pattern is on a given note.  If you are familiar with the approximate FW yield for certain lead patterns you can almost assess where this action is by visual inspection and a BW measurement.  The classic 3-2-1-0 pattern or ever the more modern 4-3-2-1-0 pattern across the scale (1/2" leads) is probably going to be in the ballpark. So, if those patterns yield a reasonable BW of 36-38 grams you likely don't have an AR reconfiguration problem.  Of course, that won't substitute for actual on the bench analysis but it's a good quick check and you won't end up doing something like this:

These principles are pretty basic and also reliable.  The spreadsheet I posted gives you a way to assess the proper SW to accompany any given action and show whether or not a modification of the action ratio either via new knuckle position or, maybe, a capstan move, is necessary.

David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-14-2025 01:06
From: Chris Chernobieff
Subject: FW Spreadsheet for Renner KMD

Fw gives you a false read. And because it does, the entire current system of measurement is incorrect. One may think they are getting a controlled and even inertia but its the opposite. Fw does not tell you the correct amount of lead to put in the key or where to put it. You can use infinite number of combinations of grams, # of leads, and locations that will get the same static key to move. The only reason its been accepted for so long is because its probably in a little better shape than before it was worked on. Ususally fixing friction alone fixes that.  Whats being missed is that when inertia is addressed properly, then there is a smoothness that is attained across the keyboard that gives a pianist something they dont have to think about. Like when aftertouch is not even. 

-chris

------------------------------
Chernobieff Piano Restorations

Inertia Touch Wave(ITW) The most advanced silky smooth actions.

Engineered Hygroscopic Soundboards. The strongest and lightest boards made today for acoustic projection, richness and warmth.

865-986-7720 (text only please)

"Key lead location is a separate matter, not inconsequential but not that significant in this part of the discussion".

Statements like this is a result of using Static balance measurements to predetermine a dynamic motion. It puts you in the ballpark so to speak. But it's like comparing 150 grit sandpaper to a polished surface. It doesn't work like you think. In my R&D in the early stages, I placed different lead weights in various locations. And measured the rotation speed of many different configurations. Its possible to have the exact everything in static terms (AR,SW,FW,BW and friction) and have different rotation speeds. There are other factors that alter the speeds, one of which is lead configuration. So when you shift a lead forward to achieve a target FW your hiding a mass problem by using more leverage. BtW, there was a really wierd rotation (slow fast)when a lot of lead was place near the fulcrum as Steinway use to do. I ended up just classifying it as another system I didn't want to use. And last but not least, any true inertia equatiion has both mass and leverage in it, so each lead location would have to be part of the equation. See how silly the above quote is now?

-chris

------------------------------
Chernobieff Piano Restorations

Inertia Touch Wave(ITW) The most advanced silky smooth actions.

Engineered Hygroscopic Soundboards. The strongest and lightest boards made today for acoustic projection, richness and warmth.

865-986-7720 (text only please)

Original Message:
Sent: 06-16-2025 23:01
From: David Love
Subject: FW Spreadsheet for Renner KMD

I am reposting this response without the cartoon as the moderator suggested would be done.  I tried to send a message to that effect to the "contact us" link as instructed, which, of course, doesn't work.  Why am I not surprised.  If you feel the need to remove this for some reason, please advise me in advance.  

It might be noted that the moderator claims to have sent me an offer to repost if the cartoon were removed.  Never received.  You might look into that.  A better system of option to edit before just unannounced censoring would be preferable, in my opinion.  

Not looking for further discussion here.  The post and its intention speaks for itself and the offer of the spread sheets for general use, if desired, was genuine with no strings attached.

This reply explains why the FW is not a "false read" as claimed but a reliable indicator, if used properly with other variables, of how to achieve desired levels of inertia and the proper combination of SW and AR that leads to that.  In the various methods cited, all roads lead to Rome, as it were.  This is one simple method of getting there.  I won't comment here further on the references to friction or aftertouch that were part of that post because they are irrelevant in this discussion. There are other non sequiturs in there as well, for example; "the reason its (sic) been accepted for so long..." which I might comment on if I could fathom what was meant.  The post to which I was replying is copied at the bottom for context.  I'm waiting for someone to say "but mass is not the same as weight".  No, it isn't.  But as long as we're talking about balancing actions here on earth, the two terms are interchangeable--I wanted to get ahead of that.  If you ship off to the Moon or Mars, of course, you will have to reconsider.  And Godspeed.  

--------------------------------------------------------------------------------------------------------------------- 

Subject: RE: FW Spreadsheet for Renner KMD

That's incorrect.  The FW required to achieve a targeted BW is directly proportional to the relationship between the AR and the SW and that relationship is the main driver of inertia.  Key lead location is a separate matter, not inconsequential but not that significant in this part of the discussion.  

If you have an AR of 6.0 and a SW that for a BW of 37 grams requires a FW of 32 grams, that AR:SW relationship will yield some specific level of inertia primarily driven by the AR:SW relationship with a smaller contribution by the key and the leads and virtually no contribution by the wippen (see Gravagne's, Voit's or Rhodes' comments on that subject for reference.)

Now, if you increase the SW in that system by 1 gram with the same target of 37g balance weight, you will require a FW of + 6 grams to achieve that.  An AR of 6.0 means a change in the SW of 1 gram yields a change of 6 grams at the key and will require adding 6 grams of FW to offset that.  Basic concept.  The inertia will necessarily be higher in this iteration because the mass being accelerated by the same AR is higher (not to mention a small but measurable increase in the inertia because of the added lead).  That change is reflected in the FW required to achieve the requisite BW and is always proportional to the change in inertia.

Let me restate; changes in inertia will always be proportional to the FW change if the two other variables are held constant, in our case the BW and the AR.  

So in the Stanwood system, he has determined, by outlining the FW maximum, when you are crossing that FW ceiling that is an indication that the AR:SW relationship is not advantageous.

Obviously, there are some ways to confound those conclusions if you don't hold the BW and AR constant.  But you are then comparing apples to oranges.  Only if the BW and AR remain constant can you compare the two AR:SW relationships and interpret that through the FW levels AND those levels are note specific with higher ceilings in the bass and lower ceilings in the treble (see my spreadsheet for clarification).  

In the "Actions to Die For" method put forth by Fandrich and Rhodes, the ITF number they derive is based on this relationship (primarily) because that's the main driver of inertia.  In the Gravagne system the conclusion he draws about ideal hammer weight based on measuring the levers takes into account the same relationship.  In the Stanwood system the same principle applies.  

My simplified system for determining proper levels of inertia and the correct AR:SW relationship starts with a presetting a FW target of about 80-85% of FW maximum as outlined by Stanwood (though my numbers differ just slightly).  For me, and by my analysis and discussions with both Gravagne and Rhodes, that is the sweet spot.  By presetting the FW and finding the SW that yields a normal BW of 36 - 38 grams you will guarantee an AR:SW relationship that produces an action with inertia in the desired zone, an action to die for, or whatever moniker you wish to assign.  It works, and it works every time.  

What happens when you wander outside of that target by, for example, choosing a BW target of 42 grams or of 32 grams?  That's for another discussion but if you think about it long enough you will see that FW must be considered along with the target BW.  Those two variables alone, however, will tell you a lot in assessing an action.  For example, let's say you have an action that has a BW of 45 grams and a FW that is already 100% of maximum or simply has a lot of lead to suspicious levels.  To bring that action down to a compliant BW in this system you would have to further exceed the 100% value by another 8 grams or so and that would be an indication that you have to alter the AR to make it work properly, at least in terms of controlling inertia. 

Similarly, if you have an action that weighs off at 32 grams BW and the FWs are low, around 70% of maximum then you can assume, correctly, that removing yet more lead to raise the BW will put that action below a minimum threshold of FW (we haven't really talked about that but there is a floor as well as a ceiling).  In that case, the inertia will be predictably very low, too low in fact.  Actions where the inertia is too low don't give adequate feedback to the player, especially high level players.  So don't get too hung up on low inertia or that lower must be better.  There is a point of diminishing returns.

But this is an easy way to quickly assess an action by just measuring the BW and seeing what the lead pattern is on a given note.  If you are familiar with the approximate FW yield for certain lead patterns you can almost assess where this action is by visual inspection and a BW measurement.  The classic 3-2-1-0 pattern or ever the more modern 4-3-2-1-0 pattern across the scale (1/2" leads) is probably going to be in the ballpark. So, if those patterns yield a reasonable BW of 36-38 grams you likely don't have an AR reconfiguration problem.  Of course, that won't substitute for actual on the bench analysis but it's a good quick check and you won't end up doing something like this:

These principles are pretty basic and also reliable.  The spreadsheet I posted gives you a way to assess the proper SW to accompany any given action and show whether or not a modification of the action ratio either via new knuckle position or, maybe, a capstan move, is necessary.

David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-14-2025 01:06
From: Chris Chernobieff
Subject: FW Spreadsheet for Renner KMD

Fw gives you a false read. And because it does, the entire current system of measurement is incorrect. One may think they are getting a controlled and even inertia but its the opposite. Fw does not tell you the correct amount of lead to put in the key or where to put it. You can use infinite number of combinations of grams, # of leads, and locations that will get the same static key to move. The only reason its been accepted for so long is because its probably in a little better shape than before it was worked on. Ususally fixing friction alone fixes that.  Whats being missed is that when inertia is addressed properly, then there is a smoothness that is attained across the keyboard that gives a pianist something they dont have to think about. Like when aftertouch is not even. 

-chris

------------------------------
Chernobieff Piano Restorations

Inertia Touch Wave(ITW) The most advanced silky smooth actions.

Engineered Hygroscopic Soundboards. The strongest and lightest boards made today for acoustic projection, richness and warmth.

865-986-7720 (text only please)

I am reposting this response without the cartoon as the moderator suggested would be done.  I tried to send a message to that effect to the "contact us" link as instructed, which, of course, doesn't work.  Why am I not surprised.  If you feel the need to remove this for some reason, please advise me in advance.  

It might be noted that the moderator claims to have sent me an offer to repost if the cartoon were removed.  Never received.  You might look into that.  A better system of option to edit before just unannounced censoring would be preferable, in my opinion.  

Not looking for further discussion here.  The post and its intention speaks for itself and the offer of the spread sheets for general use, if desired, was genuine with no strings attached.

This reply explains why the FW is not a "false read" as claimed but a reliable indicator, if used properly with other variables, of how to achieve desired levels of inertia and the proper combination of SW and AR that leads to that.  In the various methods cited, all roads lead to Rome, as it were.  This is one simple method of getting there.  I won't comment here further on the references to friction or aftertouch that were part of that post because they are irrelevant in this discussion. There are other non sequiturs in there as well, for example; "the reason its (sic) been accepted for so long..." which I might comment on if I could fathom what was meant.  The post to which I was replying is copied at the bottom for context.  I'm waiting for someone to say "but mass is not the same as weight".  No, it isn't.  But as long as we're talking about balancing actions here on earth, the two terms are interchangeable--I wanted to get ahead of that.  If you ship off to the Moon or Mars, of course, you will have to reconsider.  And Godspeed.  

--------------------------------------------------------------------------------------------------------------------- 

Subject: RE: FW Spreadsheet for Renner KMD

That's incorrect.  The FW required to achieve a targeted BW is directly proportional to the relationship between the AR and the SW and that relationship is the main driver of inertia.  Key lead location is a separate matter, not inconsequential but not that significant in this part of the discussion.  

If you have an AR of 6.0 and a SW that for a BW of 37 grams requires a FW of 32 grams, that AR:SW relationship will yield some specific level of inertia primarily driven by the AR:SW relationship with a smaller contribution by the key and the leads and virtually no contribution by the wippen (see Gravagne's, Voit's or Rhodes' comments on that subject for reference.)

Now, if you increase the SW in that system by 1 gram with the same target of 37g balance weight, you will require a FW of + 6 grams to achieve that.  An AR of 6.0 means a change in the SW of 1 gram yields a change of 6 grams at the key and will require adding 6 grams of FW to offset that.  Basic concept.  The inertia will necessarily be higher in this iteration because the mass being accelerated by the same AR is higher (not to mention a small but measurable increase in the inertia because of the added lead).  That change is reflected in the FW required to achieve the requisite BW and is always proportional to the change in inertia.

Let me restate; changes in inertia will always be proportional to the FW change if the two other variables are held constant, in our case the BW and the AR.  

So in the Stanwood system, he has determined, by outlining the FW maximum, when you are crossing that FW ceiling that is an indication that the AR:SW relationship is not advantageous.

Obviously, there are some ways to confound those conclusions if you don't hold the BW and AR constant.  But you are then comparing apples to oranges.  Only if the BW and AR remain constant can you compare the two AR:SW relationships and interpret that through the FW levels AND those levels are note specific with higher ceilings in the bass and lower ceilings in the treble (see my spreadsheet for clarification).  

In the "Actions to Die For" method put forth by Fandrich and Rhodes, the ITF number they derive is based on this relationship (primarily) because that's the main driver of inertia.  In the Gravagne system the conclusion he draws about ideal hammer weight based on measuring the levers takes into account the same relationship.  In the Stanwood system the same principle applies.  

My simplified system for determining proper levels of inertia and the correct AR:SW relationship starts with a presetting a FW target of about 80-85% of FW maximum as outlined by Stanwood (though my numbers differ just slightly).  For me, and by my analysis and discussions with both Gravagne and Rhodes, that is the sweet spot.  By presetting the FW and finding the SW that yields a normal BW of 36 - 38 grams you will guarantee an AR:SW relationship that produces an action with inertia in the desired zone, an action to die for, or whatever moniker you wish to assign.  It works, and it works every time.  

What happens when you wander outside of that target by, for example, choosing a BW target of 42 grams or of 32 grams?  That's for another discussion but if you think about it long enough you will see that FW must be considered along with the target BW.  Those two variables alone, however, will tell you a lot in assessing an action.  For example, let's say you have an action that has a BW of 45 grams and a FW that is already 100% of maximum or simply has a lot of lead to suspicious levels.  To bring that action down to a compliant BW in this system you would have to further exceed the 100% value by another 8 grams or so and that would be an indication that you have to alter the AR to make it work properly, at least in terms of controlling inertia. 

Similarly, if you have an action that weighs off at 32 grams BW and the FWs are low, around 70% of maximum then you can assume, correctly, that removing yet more lead to raise the BW will put that action below a minimum threshold of FW (we haven't really talked about that but there is a floor as well as a ceiling).  In that case, the inertia will be predictably very low, too low in fact.  Actions where the inertia is too low don't give adequate feedback to the player, especially high level players.  So don't get too hung up on low inertia or that lower must be better.  There is a point of diminishing returns.

But this is an easy way to quickly assess an action by just measuring the BW and seeing what the lead pattern is on a given note.  If you are familiar with the approximate FW yield for certain lead patterns you can almost assess where this action is by visual inspection and a BW measurement.  The classic 3-2-1-0 pattern or ever the more modern 4-3-2-1-0 pattern across the scale (1/2" leads) is probably going to be in the ballpark. So, if those patterns yield a reasonable BW of 36-38 grams you likely don't have an AR reconfiguration problem.  Of course, that won't substitute for actual on the bench analysis but it's a good quick check and you won't end up doing something like this:

These principles are pretty basic and also reliable.  The spreadsheet I posted gives you a way to assess the proper SW to accompany any given action and show whether or not a modification of the action ratio either via new knuckle position or, maybe, a capstan move, is necessary.

David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-14-2025 01:06
From: Chris Chernobieff
Subject: FW Spreadsheet for Renner KMD

Fw gives you a false read. And because it does, the entire current system of measurement is incorrect. One may think they are getting a controlled and even inertia but its the opposite. Fw does not tell you the correct amount of lead to put in the key or where to put it. You can use infinite number of combinations of grams, # of leads, and locations that will get the same static key to move. The only reason its been accepted for so long is because its probably in a little better shape than before it was worked on. Ususally fixing friction alone fixes that.  Whats being missed is that when inertia is addressed properly, then there is a smoothness that is attained across the keyboard that gives a pianist something they dont have to think about. Like when aftertouch is not even. 

-chris

------------------------------
Chernobieff Piano Restorations

Inertia Touch Wave(ITW) The most advanced silky smooth actions.

Engineered Hygroscopic Soundboards. The strongest and lightest boards made today for acoustic projection, richness and warmth.

865-986-7720 (text only please)

Jeez, I wanted that Taco graphic!. Ok,, on and off topic. During Covid, there were countless questionable political posts regarding the entire situation that were left standing.

Now we have a taco graphic that was removed. And I want it! Over reaction??? Nanny State??

I get it everybody! Piano Tech is for Piano Tech. But, TACO is directly affecting our business.

We all need the current political discussion and somewhere that we can start a thread.

I ask the moderators this??

Should we open this debate in PTG-L or somewhere else? I will certainly engage.

As members of PTG, we need to to debate our current political environment as it it as important, if not more, than replacing agraffes,

Where can we do this. I/m asking Nanny Police!

I am reposting this response without the cartoon as the moderator suggested would be done.  I tried to send a message to that effect to the "contact us" link as instructed, which, of course, doesn't work.  Why am I not surprised.  If you feel the need to remove this for some reason, please advise me in advance.  

It might be noted that the moderator claims to have sent me an offer to repost if the cartoon were removed.  Never received.  You might look into that.  A better system of option to edit before just unannounced censoring would be preferable, in my opinion.  

Not looking for further discussion here.  The post and its intention speaks for itself and the offer of the spread sheets for general use, if desired, was genuine with no strings attached.

This reply explains why the FW is not a "false read" as claimed but a reliable indicator, if used properly with other variables, of how to achieve desired levels of inertia and the proper combination of SW and AR that leads to that.  In the various methods cited, all roads lead to Rome, as it were.  This is one simple method of getting there.  I won't comment here further on the references to friction or aftertouch that were part of that post because they are irrelevant in this discussion. There are other non sequiturs in there as well, for example; "the reason its (sic) been accepted for so long..." which I might comment on if I could fathom what was meant.  The post to which I was replying is copied at the bottom for context.  I'm waiting for someone to say "but mass is not the same as weight".  No, it isn't.  But as long as we're talking about balancing actions here on earth, the two terms are interchangeable--I wanted to get ahead of that.  If you ship off to the Moon or Mars, of course, you will have to reconsider.  And Godspeed.  

--------------------------------------------------------------------------------------------------------------------- 

Subject: RE: FW Spreadsheet for Renner KMD

That's incorrect.  The FW required to achieve a targeted BW is directly proportional to the relationship between the AR and the SW and that relationship is the main driver of inertia.  Key lead location is a separate matter, not inconsequential but not that significant in this part of the discussion.  

If you have an AR of 6.0 and a SW that for a BW of 37 grams requires a FW of 32 grams, that AR:SW relationship will yield some specific level of inertia primarily driven by the AR:SW relationship with a smaller contribution by the key and the leads and virtually no contribution by the wippen (see Gravagne's, Voit's or Rhodes' comments on that subject for reference.)

Now, if you increase the SW in that system by 1 gram with the same target of 37g balance weight, you will require a FW of + 6 grams to achieve that.  An AR of 6.0 means a change in the SW of 1 gram yields a change of 6 grams at the key and will require adding 6 grams of FW to offset that.  Basic concept.  The inertia will necessarily be higher in this iteration because the mass being accelerated by the same AR is higher (not to mention a small but measurable increase in the inertia because of the added lead).  That change is reflected in the FW required to achieve the requisite BW and is always proportional to the change in inertia.

Let me restate; changes in inertia will always be proportional to the FW change if the two other variables are held constant, in our case the BW and the AR.  

So in the Stanwood system, he has determined, by outlining the FW maximum, when you are crossing that FW ceiling that is an indication that the AR:SW relationship is not advantageous.

Obviously, there are some ways to confound those conclusions if you don't hold the BW and AR constant.  But you are then comparing apples to oranges.  Only if the BW and AR remain constant can you compare the two AR:SW relationships and interpret that through the FW levels AND those levels are note specific with higher ceilings in the bass and lower ceilings in the treble (see my spreadsheet for clarification).  

In the "Actions to Die For" method put forth by Fandrich and Rhodes, the ITF number they derive is based on this relationship (primarily) because that's the main driver of inertia.  In the Gravagne system the conclusion he draws about ideal hammer weight based on measuring the levers takes into account the same relationship.  In the Stanwood system the same principle applies.  

My simplified system for determining proper levels of inertia and the correct AR:SW relationship starts with a presetting a FW target of about 80-85% of FW maximum as outlined by Stanwood (though my numbers differ just slightly).  For me, and by my analysis and discussions with both Gravagne and Rhodes, that is the sweet spot.  By presetting the FW and finding the SW that yields a normal BW of 36 - 38 grams you will guarantee an AR:SW relationship that produces an action with inertia in the desired zone, an action to die for, or whatever moniker you wish to assign.  It works, and it works every time.  

What happens when you wander outside of that target by, for example, choosing a BW target of 42 grams or of 32 grams?  That's for another discussion but if you think about it long enough you will see that FW must be considered along with the target BW.  Those two variables alone, however, will tell you a lot in assessing an action.  For example, let's say you have an action that has a BW of 45 grams and a FW that is already 100% of maximum or simply has a lot of lead to suspicious levels.  To bring that action down to a compliant BW in this system you would have to further exceed the 100% value by another 8 grams or so and that would be an indication that you have to alter the AR to make it work properly, at least in terms of controlling inertia. 

Similarly, if you have an action that weighs off at 32 grams BW and the FWs are low, around 70% of maximum then you can assume, correctly, that removing yet more lead to raise the BW will put that action below a minimum threshold of FW (we haven't really talked about that but there is a floor as well as a ceiling).  In that case, the inertia will be predictably very low, too low in fact.  Actions where the inertia is too low don't give adequate feedback to the player, especially high level players.  So don't get too hung up on low inertia or that lower must be better.  There is a point of diminishing returns.

But this is an easy way to quickly assess an action by just measuring the BW and seeing what the lead pattern is on a given note.  If you are familiar with the approximate FW yield for certain lead patterns you can almost assess where this action is by visual inspection and a BW measurement.  The classic 3-2-1-0 pattern or ever the more modern 4-3-2-1-0 pattern across the scale (1/2" leads) is probably going to be in the ballpark. So, if those patterns yield a reasonable BW of 36-38 grams you likely don't have an AR reconfiguration problem.  Of course, that won't substitute for actual on the bench analysis but it's a good quick check and you won't end up doing something like this:

These principles are pretty basic and also reliable.  The spreadsheet I posted gives you a way to assess the proper SW to accompany any given action and show whether or not a modification of the action ratio either via new knuckle position or, maybe, a capstan move, is necessary.

David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-14-2025 01:06
From: Chris Chernobieff
Subject: FW Spreadsheet for Renner KMD

Fw gives you a false read. And because it does, the entire current system of measurement is incorrect. One may think they are getting a controlled and even inertia but its the opposite. Fw does not tell you the correct amount of lead to put in the key or where to put it. You can use infinite number of combinations of grams, # of leads, and locations that will get the same static key to move. The only reason its been accepted for so long is because its probably in a little better shape than before it was worked on. Ususally fixing friction alone fixes that.  Whats being missed is that when inertia is addressed properly, then there is a smoothness that is attained across the keyboard that gives a pianist something they dont have to think about. Like when aftertouch is not even. 

-chris

------------------------------
Chernobieff Piano Restorations

Inertia Touch Wave(ITW) The most advanced silky smooth actions.

Engineered Hygroscopic Soundboards. The strongest and lightest boards made today for acoustic projection, richness and warmth.

865-986-7720 (text only please)

I am reposting this response without the cartoon as the moderator suggested would be done.  I tried to send a message to that effect to the "contact us" link as instructed, which, of course, doesn't work.  Why am I not surprised.  If you feel the need to remove this for some reason, please advise me in advance.  

It might be noted that the moderator claims to have sent me an offer to repost if the cartoon were removed.  Never received.  You might look into that.  A better system of option to edit before just unannounced censoring would be preferable, in my opinion.  

Not looking for further discussion here.  The post and its intention speaks for itself and the offer of the spread sheets for general use, if desired, was genuine with no strings attached.

This reply explains why the FW is not a "false read" as claimed but a reliable indicator, if used properly with other variables, of how to achieve desired levels of inertia and the proper combination of SW and AR that leads to that.  In the various methods cited, all roads lead to Rome, as it were.  This is one simple method of getting there.  I won't comment here further on the references to friction or aftertouch that were part of that post because they are irrelevant in this discussion. There are other non sequiturs in there as well, for example; "the reason its (sic) been accepted for so long..." which I might comment on if I could fathom what was meant.  The post to which I was replying is copied at the bottom for context.  I'm waiting for someone to say "but mass is not the same as weight".  No, it isn't.  But as long as we're talking about balancing actions here on earth, the two terms are interchangeable--I wanted to get ahead of that.  If you ship off to the Moon or Mars, of course, you will have to reconsider.  And Godspeed.  

--------------------------------------------------------------------------------------------------------------------- 

Subject: RE: FW Spreadsheet for Renner KMD

That's incorrect.  The FW required to achieve a targeted BW is directly proportional to the relationship between the AR and the SW and that relationship is the main driver of inertia.  Key lead location is a separate matter, not inconsequential but not that significant in this part of the discussion.  

If you have an AR of 6.0 and a SW that for a BW of 37 grams requires a FW of 32 grams, that AR:SW relationship will yield some specific level of inertia primarily driven by the AR:SW relationship with a smaller contribution by the key and the leads and virtually no contribution by the wippen (see Gravagne's, Voit's or Rhodes' comments on that subject for reference.)

Now, if you increase the SW in that system by 1 gram with the same target of 37g balance weight, you will require a FW of + 6 grams to achieve that.  An AR of 6.0 means a change in the SW of 1 gram yields a change of 6 grams at the key and will require adding 6 grams of FW to offset that.  Basic concept.  The inertia will necessarily be higher in this iteration because the mass being accelerated by the same AR is higher (not to mention a small but measurable increase in the inertia because of the added lead).  That change is reflected in the FW required to achieve the requisite BW and is always proportional to the change in inertia.

Let me restate; changes in inertia will always be proportional to the FW change if the two other variables are held constant, in our case the BW and the AR.  

So in the Stanwood system, he has determined, by outlining the FW maximum, when you are crossing that FW ceiling that is an indication that the AR:SW relationship is not advantageous.

Obviously, there are some ways to confound those conclusions if you don't hold the BW and AR constant.  But you are then comparing apples to oranges.  Only if the BW and AR remain constant can you compare the two AR:SW relationships and interpret that through the FW levels AND those levels are note specific with higher ceilings in the bass and lower ceilings in the treble (see my spreadsheet for clarification).  

In the "Actions to Die For" method put forth by Fandrich and Rhodes, the ITF number they derive is based on this relationship (primarily) because that's the main driver of inertia.  In the Gravagne system the conclusion he draws about ideal hammer weight based on measuring the levers takes into account the same relationship.  In the Stanwood system the same principle applies.  

My simplified system for determining proper levels of inertia and the correct AR:SW relationship starts with a presetting a FW target of about 80-85% of FW maximum as outlined by Stanwood (though my numbers differ just slightly).  For me, and by my analysis and discussions with both Gravagne and Rhodes, that is the sweet spot.  By presetting the FW and finding the SW that yields a normal BW of 36 - 38 grams you will guarantee an AR:SW relationship that produces an action with inertia in the desired zone, an action to die for, or whatever moniker you wish to assign.  It works, and it works every time.  

What happens when you wander outside of that target by, for example, choosing a BW target of 42 grams or of 32 grams?  That's for another discussion but if you think about it long enough you will see that FW must be considered along with the target BW.  Those two variables alone, however, will tell you a lot in assessing an action.  For example, let's say you have an action that has a BW of 45 grams and a FW that is already 100% of maximum or simply has a lot of lead to suspicious levels.  To bring that action down to a compliant BW in this system you would have to further exceed the 100% value by another 8 grams or so and that would be an indication that you have to alter the AR to make it work properly, at least in terms of controlling inertia. 

Similarly, if you have an action that weighs off at 32 grams BW and the FWs are low, around 70% of maximum then you can assume, correctly, that removing yet more lead to raise the BW will put that action below a minimum threshold of FW (we haven't really talked about that but there is a floor as well as a ceiling).  In that case, the inertia will be predictably very low, too low in fact.  Actions where the inertia is too low don't give adequate feedback to the player, especially high level players.  So don't get too hung up on low inertia or that lower must be better.  There is a point of diminishing returns.

But this is an easy way to quickly assess an action by just measuring the BW and seeing what the lead pattern is on a given note.  If you are familiar with the approximate FW yield for certain lead patterns you can almost assess where this action is by visual inspection and a BW measurement.  The classic 3-2-1-0 pattern or ever the more modern 4-3-2-1-0 pattern across the scale (1/2" leads) is probably going to be in the ballpark. So, if those patterns yield a reasonable BW of 36-38 grams you likely don't have an AR reconfiguration problem.  Of course, that won't substitute for actual on the bench analysis but it's a good quick check and you won't end up doing something like this:

These principles are pretty basic and also reliable.  The spreadsheet I posted gives you a way to assess the proper SW to accompany any given action and show whether or not a modification of the action ratio either via new knuckle position or, maybe, a capstan move, is necessary.

David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-14-2025 01:06
From: Chris Chernobieff
Subject: FW Spreadsheet for Renner KMD

Fw gives you a false read. And because it does, the entire current system of measurement is incorrect. One may think they are getting a controlled and even inertia but its the opposite. Fw does not tell you the correct amount of lead to put in the key or where to put it. You can use infinite number of combinations of grams, # of leads, and locations that will get the same static key to move. The only reason its been accepted for so long is because its probably in a little better shape than before it was worked on. Ususally fixing friction alone fixes that.  Whats being missed is that when inertia is addressed properly, then there is a smoothness that is attained across the keyboard that gives a pianist something they dont have to think about. Like when aftertouch is not even. 

-chris

------------------------------
Chernobieff Piano Restorations

Inertia Touch Wave(ITW) The most advanced silky smooth actions.

Engineered Hygroscopic Soundboards. The strongest and lightest boards made today for acoustic projection, richness and warmth.

865-986-7720 (text only please)

David,

I have verified on my end that my message was sent to you yesterday offering to edit the post and replace it, since I didn't want to disrupt the technical discourse if possible.  I can provide a screenshot to verify, if you want. Feel free to contact me directly instead of dropping things on a forum where I might miss them. I'm always happy to answer questions or verify things.

re; the jabs towards myself and my team from several members here - I would gently remind everyone we are VOLUNTEERS that just want to keep the PTG forums an effective place for business to occur.  This Task Group has a very high turnover rate, and the current team was not active during Covid or a part of whatever moderation occurred then. It's not hard to understand why, given the punching bag some have turned us into.

There are Community Guidelines you all agreed to follow by using this platform.  We are enforcing those guidelines when things are reported and ruled to be in violation (such as an obviously political sticker/image…), but we DO NOT actively police comments. It's fine if you disagree with this, but instead of beating down your fellow PTG members, volunteers, and colleagues, that give a significant amount of their time, perhaps consider submitting an RFA to change the Guidelines, joining the Communications Task Group to influence future moderation, or speak at Council and raise your concerns to the membership and the Board. 

I am resigning this position in July at Convention.  I wish the next Chair and Communications team good luck and godspeed, and welcome new volunteers. I've done my best with the cumbersome tools available, and have tried to provide a degree of transparency that I personally feel has been lacking in this role in the past that the membership deserves.

Also, I would suggest creating a new thread on PTG-L if you would like to continue this kind of moderation discussion, which I fully welcome and am happy to participate in.

I am reposting this response without the cartoon as the moderator suggested would be done.  I tried to send a message to that effect to the "contact us" link as instructed, which, of course, doesn't work.  Why am I not surprised.  If you feel the need to remove this for some reason, please advise me in advance.  

It might be noted that the moderator claims to have sent me an offer to repost if the cartoon were removed.  Never received.  You might look into that.  A better system of option to edit before just unannounced censoring would be preferable, in my opinion.  

Not looking for further discussion here.  The post and its intention speaks for itself and the offer of the spread sheets for general use, if desired, was genuine with no strings attached.

This reply explains why the FW is not a "false read" as claimed but a reliable indicator, if used properly with other variables, of how to achieve desired levels of inertia and the proper combination of SW and AR that leads to that.  In the various methods cited, all roads lead to Rome, as it were.  This is one simple method of getting there.  I won't comment here further on the references to friction or aftertouch that were part of that post because they are irrelevant in this discussion. There are other non sequiturs in there as well, for example; "the reason its (sic) been accepted for so long..." which I might comment on if I could fathom what was meant.  The post to which I was replying is copied at the bottom for context.  I'm waiting for someone to say "but mass is not the same as weight".  No, it isn't.  But as long as we're talking about balancing actions here on earth, the two terms are interchangeable--I wanted to get ahead of that.  If you ship off to the Moon or Mars, of course, you will have to reconsider.  And Godspeed.  

--------------------------------------------------------------------------------------------------------------------- 

Subject: RE: FW Spreadsheet for Renner KMD

That's incorrect.  The FW required to achieve a targeted BW is directly proportional to the relationship between the AR and the SW and that relationship is the main driver of inertia.  Key lead location is a separate matter, not inconsequential but not that significant in this part of the discussion.  

If you have an AR of 6.0 and a SW that for a BW of 37 grams requires a FW of 32 grams, that AR:SW relationship will yield some specific level of inertia primarily driven by the AR:SW relationship with a smaller contribution by the key and the leads and virtually no contribution by the wippen (see Gravagne's, Voit's or Rhodes' comments on that subject for reference.)

Now, if you increase the SW in that system by 1 gram with the same target of 37g balance weight, you will require a FW of + 6 grams to achieve that.  An AR of 6.0 means a change in the SW of 1 gram yields a change of 6 grams at the key and will require adding 6 grams of FW to offset that.  Basic concept.  The inertia will necessarily be higher in this iteration because the mass being accelerated by the same AR is higher (not to mention a small but measurable increase in the inertia because of the added lead).  That change is reflected in the FW required to achieve the requisite BW and is always proportional to the change in inertia.

Let me restate; changes in inertia will always be proportional to the FW change if the two other variables are held constant, in our case the BW and the AR.  

So in the Stanwood system, he has determined, by outlining the FW maximum, when you are crossing that FW ceiling that is an indication that the AR:SW relationship is not advantageous.

Obviously, there are some ways to confound those conclusions if you don't hold the BW and AR constant.  But you are then comparing apples to oranges.  Only if the BW and AR remain constant can you compare the two AR:SW relationships and interpret that through the FW levels AND those levels are note specific with higher ceilings in the bass and lower ceilings in the treble (see my spreadsheet for clarification).  

In the "Actions to Die For" method put forth by Fandrich and Rhodes, the ITF number they derive is based on this relationship (primarily) because that's the main driver of inertia.  In the Gravagne system the conclusion he draws about ideal hammer weight based on measuring the levers takes into account the same relationship.  In the Stanwood system the same principle applies.  

My simplified system for determining proper levels of inertia and the correct AR:SW relationship starts with a presetting a FW target of about 80-85% of FW maximum as outlined by Stanwood (though my numbers differ just slightly).  For me, and by my analysis and discussions with both Gravagne and Rhodes, that is the sweet spot.  By presetting the FW and finding the SW that yields a normal BW of 36 - 38 grams you will guarantee an AR:SW relationship that produces an action with inertia in the desired zone, an action to die for, or whatever moniker you wish to assign.  It works, and it works every time.  

What happens when you wander outside of that target by, for example, choosing a BW target of 42 grams or of 32 grams?  That's for another discussion but if you think about it long enough you will see that FW must be considered along with the target BW.  Those two variables alone, however, will tell you a lot in assessing an action.  For example, let's say you have an action that has a BW of 45 grams and a FW that is already 100% of maximum or simply has a lot of lead to suspicious levels.  To bring that action down to a compliant BW in this system you would have to further exceed the 100% value by another 8 grams or so and that would be an indication that you have to alter the AR to make it work properly, at least in terms of controlling inertia. 

Similarly, if you have an action that weighs off at 32 grams BW and the FWs are low, around 70% of maximum then you can assume, correctly, that removing yet more lead to raise the BW will put that action below a minimum threshold of FW (we haven't really talked about that but there is a floor as well as a ceiling).  In that case, the inertia will be predictably very low, too low in fact.  Actions where the inertia is too low don't give adequate feedback to the player, especially high level players.  So don't get too hung up on low inertia or that lower must be better.  There is a point of diminishing returns.

But this is an easy way to quickly assess an action by just measuring the BW and seeing what the lead pattern is on a given note.  If you are familiar with the approximate FW yield for certain lead patterns you can almost assess where this action is by visual inspection and a BW measurement.  The classic 3-2-1-0 pattern or ever the more modern 4-3-2-1-0 pattern across the scale (1/2" leads) is probably going to be in the ballpark. So, if those patterns yield a reasonable BW of 36-38 grams you likely don't have an AR reconfiguration problem.  Of course, that won't substitute for actual on the bench analysis but it's a good quick check and you won't end up doing something like this:

These principles are pretty basic and also reliable.  The spreadsheet I posted gives you a way to assess the proper SW to accompany any given action and show whether or not a modification of the action ratio either via new knuckle position or, maybe, a capstan move, is necessary.

David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-14-2025 01:06
From: Chris Chernobieff
Subject: FW Spreadsheet for Renner KMD

Fw gives you a false read. And because it does, the entire current system of measurement is incorrect. One may think they are getting a controlled and even inertia but its the opposite. Fw does not tell you the correct amount of lead to put in the key or where to put it. You can use infinite number of combinations of grams, # of leads, and locations that will get the same static key to move. The only reason its been accepted for so long is because its probably in a little better shape than before it was worked on. Ususally fixing friction alone fixes that.  Whats being missed is that when inertia is addressed properly, then there is a smoothness that is attained across the keyboard that gives a pianist something they dont have to think about. Like when aftertouch is not even. 

-chris

------------------------------
Chernobieff Piano Restorations

Inertia Touch Wave(ITW) The most advanced silky smooth actions.

Engineered Hygroscopic Soundboards. The strongest and lightest boards made today for acoustic projection, richness and warmth.

865-986-7720 (text only please)

David,

I have verified on my end that my message was sent to you yesterday offering to edit the post and replace it, since I didn't want to disrupt the technical discourse if possible.  I can provide a screenshot to verify, if you want. Feel free to contact me directly instead of dropping things on a forum where I might miss them. I'm always happy to answer questions or verify things.

re; the jabs towards myself and my team from several members here - I would gently remind everyone we are VOLUNTEERS that just want to keep the PTG forums an effective place for business to occur.  This Task Group has a very high turnover rate, and the current team was not active during Covid or a part of whatever moderation occurred then. It's not hard to understand why, given the punching bag some have turned us into.

There are Community Guidelines you all agreed to follow by using this platform.  We are enforcing those guidelines when things are reported and ruled to be in violation (such as an obviously political sticker/image…), but we DO NOT actively police comments. It's fine if you disagree with this, but instead of beating down your fellow PTG members, volunteers, and colleagues, that give a significant amount of their time, perhaps consider submitting an RFA to change the Guidelines, joining the Communications Task Group to influence future moderation, or speak at Council and raise your concerns to the membership and the Board. 

I am resigning this position in July at Convention.  I wish the next Chair and Communications team good luck and godspeed, and welcome new volunteers. I've done my best with the cumbersome tools available, and have tried to provide a degree of transparency that I personally feel has been lacking in this role in the past that the membership deserves.

Also, I would suggest creating a new thread on PTG-L if you would like to continue this kind of moderation discussion, which I fully welcome and am happy to participate in.

I am reposting this response without the cartoon as the moderator suggested would be done.  I tried to send a message to that effect to the "contact us" link as instructed, which, of course, doesn't work.  Why am I not surprised.  If you feel the need to remove this for some reason, please advise me in advance.  

It might be noted that the moderator claims to have sent me an offer to repost if the cartoon were removed.  Never received.  You might look into that.  A better system of option to edit before just unannounced censoring would be preferable, in my opinion.  

Not looking for further discussion here.  The post and its intention speaks for itself and the offer of the spread sheets for general use, if desired, was genuine with no strings attached.

This reply explains why the FW is not a "false read" as claimed but a reliable indicator, if used properly with other variables, of how to achieve desired levels of inertia and the proper combination of SW and AR that leads to that.  In the various methods cited, all roads lead to Rome, as it were.  This is one simple method of getting there.  I won't comment here further on the references to friction or aftertouch that were part of that post because they are irrelevant in this discussion. There are other non sequiturs in there as well, for example; "the reason its (sic) been accepted for so long..." which I might comment on if I could fathom what was meant.  The post to which I was replying is copied at the bottom for context.  I'm waiting for someone to say "but mass is not the same as weight".  No, it isn't.  But as long as we're talking about balancing actions here on earth, the two terms are interchangeable--I wanted to get ahead of that.  If you ship off to the Moon or Mars, of course, you will have to reconsider.  And Godspeed.  

--------------------------------------------------------------------------------------------------------------------- 

Subject: RE: FW Spreadsheet for Renner KMD

That's incorrect.  The FW required to achieve a targeted BW is directly proportional to the relationship between the AR and the SW and that relationship is the main driver of inertia.  Key lead location is a separate matter, not inconsequential but not that significant in this part of the discussion.  

If you have an AR of 6.0 and a SW that for a BW of 37 grams requires a FW of 32 grams, that AR:SW relationship will yield some specific level of inertia primarily driven by the AR:SW relationship with a smaller contribution by the key and the leads and virtually no contribution by the wippen (see Gravagne's, Voit's or Rhodes' comments on that subject for reference.)

Now, if you increase the SW in that system by 1 gram with the same target of 37g balance weight, you will require a FW of + 6 grams to achieve that.  An AR of 6.0 means a change in the SW of 1 gram yields a change of 6 grams at the key and will require adding 6 grams of FW to offset that.  Basic concept.  The inertia will necessarily be higher in this iteration because the mass being accelerated by the same AR is higher (not to mention a small but measurable increase in the inertia because of the added lead).  That change is reflected in the FW required to achieve the requisite BW and is always proportional to the change in inertia.

Let me restate; changes in inertia will always be proportional to the FW change if the two other variables are held constant, in our case the BW and the AR.  

So in the Stanwood system, he has determined, by outlining the FW maximum, when you are crossing that FW ceiling that is an indication that the AR:SW relationship is not advantageous.

Obviously, there are some ways to confound those conclusions if you don't hold the BW and AR constant.  But you are then comparing apples to oranges.  Only if the BW and AR remain constant can you compare the two AR:SW relationships and interpret that through the FW levels AND those levels are note specific with higher ceilings in the bass and lower ceilings in the treble (see my spreadsheet for clarification).  

In the "Actions to Die For" method put forth by Fandrich and Rhodes, the ITF number they derive is based on this relationship (primarily) because that's the main driver of inertia.  In the Gravagne system the conclusion he draws about ideal hammer weight based on measuring the levers takes into account the same relationship.  In the Stanwood system the same principle applies.  

My simplified system for determining proper levels of inertia and the correct AR:SW relationship starts with a presetting a FW target of about 80-85% of FW maximum as outlined by Stanwood (though my numbers differ just slightly).  For me, and by my analysis and discussions with both Gravagne and Rhodes, that is the sweet spot.  By presetting the FW and finding the SW that yields a normal BW of 36 - 38 grams you will guarantee an AR:SW relationship that produces an action with inertia in the desired zone, an action to die for, or whatever moniker you wish to assign.  It works, and it works every time.  

What happens when you wander outside of that target by, for example, choosing a BW target of 42 grams or of 32 grams?  That's for another discussion but if you think about it long enough you will see that FW must be considered along with the target BW.  Those two variables alone, however, will tell you a lot in assessing an action.  For example, let's say you have an action that has a BW of 45 grams and a FW that is already 100% of maximum or simply has a lot of lead to suspicious levels.  To bring that action down to a compliant BW in this system you would have to further exceed the 100% value by another 8 grams or so and that would be an indication that you have to alter the AR to make it work properly, at least in terms of controlling inertia. 

Similarly, if you have an action that weighs off at 32 grams BW and the FWs are low, around 70% of maximum then you can assume, correctly, that removing yet more lead to raise the BW will put that action below a minimum threshold of FW (we haven't really talked about that but there is a floor as well as a ceiling).  In that case, the inertia will be predictably very low, too low in fact.  Actions where the inertia is too low don't give adequate feedback to the player, especially high level players.  So don't get too hung up on low inertia or that lower must be better.  There is a point of diminishing returns.

But this is an easy way to quickly assess an action by just measuring the BW and seeing what the lead pattern is on a given note.  If you are familiar with the approximate FW yield for certain lead patterns you can almost assess where this action is by visual inspection and a BW measurement.  The classic 3-2-1-0 pattern or ever the more modern 4-3-2-1-0 pattern across the scale (1/2" leads) is probably going to be in the ballpark. So, if those patterns yield a reasonable BW of 36-38 grams you likely don't have an AR reconfiguration problem.  Of course, that won't substitute for actual on the bench analysis but it's a good quick check and you won't end up doing something like this:

These principles are pretty basic and also reliable.  The spreadsheet I posted gives you a way to assess the proper SW to accompany any given action and show whether or not a modification of the action ratio either via new knuckle position or, maybe, a capstan move, is necessary.

David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320

Original Message:
Sent: 06-14-2025 01:06
From: Chris Chernobieff
Subject: FW Spreadsheet for Renner KMD

Fw gives you a false read. And because it does, the entire current system of measurement is incorrect. One may think they are getting a controlled and even inertia but its the opposite. Fw does not tell you the correct amount of lead to put in the key or where to put it. You can use infinite number of combinations of grams, # of leads, and locations that will get the same static key to move. The only reason its been accepted for so long is because its probably in a little better shape than before it was worked on. Ususally fixing friction alone fixes that.  Whats being missed is that when inertia is addressed properly, then there is a smoothness that is attained across the keyboard that gives a pianist something they dont have to think about. Like when aftertouch is not even. 

-chris

------------------------------
Chernobieff Piano Restorations

Inertia Touch Wave(ITW) The most advanced silky smooth actions.

Engineered Hygroscopic Soundboards. The strongest and lightest boards made today for acoustic projection, richness and warmth.

865-986-7720 (text only please)