Pianotech

Joe,

In my experience it's the other way round. Bed the keyframe in the piano, then use your dip measurement to reset it outside the piano.

Peter Grey Piano Doctor 

Yes Wim, that is exactly how I bed the action frame. I use Steve Brady's knocking technique that he writes about in his book, "Under the Lid." I start with all the bolts turned up and not touching the key bed. And I make sure it is bedded with dampers down, dampers up, and then with the shift pedal depressed with dampers down and up. 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com
------------------------------


Original Message:
Sent: 02-22-2024 16:01
From: Wim Blees
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Of course, even bedding first and then setting keydip next, that dip will not be accurate except in the keybed where the glides were set. Bit I'm with Wim: aftertouch is far more important than dip. A good pianist will notice 10 mil inconsistencies far faster than than in dip (10 mils being a far greater portion of a .045" aftertouch than a .415" dip. Given that, aftertouch does need to be done in the keybed (unless of course you have the Grandworks System).

Yes Wim, that is exactly how I bed the action frame. I use Steve Brady's knocking technique that he writes about in his book, "Under the Lid." I start with all the bolts turned up and not touching the key bed. And I make sure it is bedded with dampers down, dampers up, and then with the shift pedal depressed with dampers down and up. 

I understand the Yamaha approach to differ from what Wim is advocating, in that it assumes some protrusion of the glide beyond the surface of the keyframe at the outset.  I recall reading of it somewhere, probably on this forum.

Of course, even bedding first and then setting keydip next, that dip will not be accurate except in the keybed where the glides were set. Bit I'm with Wim: aftertouch is far more important than dip. A good pianist will notice 10 mil inconsistencies far faster than than in dip (10 mils being a far greater portion of a .045" aftertouch than a .415" dip. Given that, aftertouch does need to be done in the keybed (unless of course you have the Grandworks System).

Yes Wim, that is exactly how I bed the action frame. I use Steve Brady's knocking technique that he writes about in his book, "Under the Lid." I start with all the bolts turned up and not touching the key bed. And I make sure it is bedded with dampers down, dampers up, and then with the shift pedal depressed with dampers down and up. 

Joe, 

Are saying that everything is wacked out simply by removing the action and putting it back in?  I feel like I'm missing something here. 

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com
------------------------------


Original Message:
Sent: 02-22-2024 18:20
From: Floyd Gadd
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

I understand the Yamaha approach to differ from what Wim is advocating, in that it assumes some protrusion of the glide beyond the surface of the keyframe at the outset.  I recall reading of it somewhere, probably on this forum.

------------------------------
Floyd Gadd RPT
Regina SK
(306) 502-9103


Original Message:
Sent: 02-22-2024 18:13
From: Bill Ballard
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Of course, even bedding first and then setting keydip next, that dip will not be accurate except in the keybed where the glides were set. Bit I'm with Wim: aftertouch is far more important than dip. A good pianist will notice 10 mil inconsistencies far faster than than in dip (10 mils being a far greater portion of a .045" aftertouch than a .415" dip. Given that, aftertouch does need to be done in the keybed (unless of course you have the Grandworks System).

------------------------------
William Ballard RPT
WBPS
Saxtons River VT
802-869-9107

"Our lives contain a thousand springs
and dies if one be gone
Strange that a harp of a thousand strings
should keep in tune so long."
...........Dr. Watts, "The Continental Harmony,1774


Original Message:
Sent: 02-22-2024 16:52
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Yes Wim, that is exactly how I bed the action frame. I use Steve Brady's knocking technique that he writes about in his book, "Under the Lid." I start with all the bolts turned up and not touching the key bed. And I make sure it is bedded with dampers down, dampers up, and then with the shift pedal depressed with dampers down and up. 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-22-2024 16:01
From: Wim Blees
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Peter went: "Joe, are saying that everything is wacked out simply by removing the action and putting it back in?"

If it was true that simply sliding it out of and into the same piano, then it would matter whether the dip was done in the piano or on a nearby bench, or whether that bench was done on an everyday bench, an Edwards action caddy, or a Grandworks frame. You pull it out of the piano and what ever dip you may have already set will get messed up. What's really at issue is the flexibility of the keyframe.

Joe went: "I have noticed that even the most minute change in the action caddy setting will change the key dip, which tells me that key dip is ultra-sensitive to any minute changes in bedding the action."

There are many regulating steps which are only affected by bedding in a distant, minor way, and thus don't need a consistent bedding to get done. But dip (and aftertouch) ARE sensitive to minute changes in the bedding. To mitigate this sensitivity, the two bedding surfaces (keybed and regulation bench) have to match (or at be least be replicated). I don't believe that the Edwards caddy is designed to replicate the keybed.

------------------------------
William Ballard RPT
WBPS
Saxtons River VT
802-869-9107

"Our lives contain a thousand springs
and dies if one be gone
Strange that a harp of a thousand strings
should keep in tune so long."
...........Dr. Watts, "The Continental Harmony,1774
------------------------------


Original Message:
Sent: 02-22-2024 20:34
From: Peter Grey
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Joe, 

Are saying that everything is wacked out simply by removing the action and putting it back in?  I feel like I'm missing something here. 

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com


Original Message:
Sent: 02-22-2024 18:20
From: Floyd Gadd
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

I understand the Yamaha approach to differ from what Wim is advocating, in that it assumes some protrusion of the glide beyond the surface of the keyframe at the outset.  I recall reading of it somewhere, probably on this forum.

------------------------------
Floyd Gadd RPT
Regina SK
(306) 502-9103


Original Message:
Sent: 02-22-2024 18:13
From: Bill Ballard
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Of course, even bedding first and then setting keydip next, that dip will not be accurate except in the keybed where the glides were set. Bit I'm with Wim: aftertouch is far more important than dip. A good pianist will notice 10 mil inconsistencies far faster than than in dip (10 mils being a far greater portion of a .045" aftertouch than a .415" dip. Given that, aftertouch does need to be done in the keybed (unless of course you have the Grandworks System).

------------------------------
William Ballard RPT
WBPS
Saxtons River VT
802-869-9107

"Our lives contain a thousand springs
and dies if one be gone
Strange that a harp of a thousand strings
should keep in tune so long."
...........Dr. Watts, "The Continental Harmony,1774


Original Message:
Sent: 02-22-2024 16:52
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Yes Wim, that is exactly how I bed the action frame. I use Steve Brady's knocking technique that he writes about in his book, "Under the Lid." I start with all the bolts turned up and not touching the key bed. And I make sure it is bedded with dampers down, dampers up, and then with the shift pedal depressed with dampers down and up. 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-22-2024 16:01
From: Wim Blees
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

The Edwards caddy doesn't span the entire keyframe, and the unsupported ends are subject to flexing. Also, the caddy only "beds" the balance rail and doesn't account for any crown in the front rail. 

Peter went: "Joe, are saying that everything is wacked out simply by removing the action and putting it back in?"

If it was true that simply sliding it out of and into the same piano, then it would matter whether the dip was done in the piano or on a nearby bench, or whether that bench was done on an everyday bench, an Edwards action caddy, or a Grandworks frame. You pull it out of the piano and what ever dip you may have already set will get messed up. What's really at issue is the flexibility of the keyframe.

Joe went: "I have noticed that even the most minute change in the action caddy setting will change the key dip, which tells me that key dip is ultra-sensitive to any minute changes in bedding the action."

There are many regulating steps which are only affected by bedding in a distant, minor way, and thus don't need a consistent bedding to get done. But dip (and aftertouch) ARE sensitive to minute changes in the bedding. To mitigate this sensitivity, the two bedding surfaces (keybed and regulation bench) have to match (or at be least be replicated). I don't believe that the Edwards caddy is designed to replicate the keybed.

------------------------------
William Ballard RPT
WBPS
Saxtons River VT
802-869-9107

"Our lives contain a thousand springs
and dies if one be gone
Strange that a harp of a thousand strings
should keep in tune so long."
...........Dr. Watts, "The Continental Harmony,1774
------------------------------


Original Message:
Sent: 02-22-2024 20:34
From: Peter Grey
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Joe, 

Are saying that everything is wacked out simply by removing the action and putting it back in?  I feel like I'm missing something here. 

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com


Original Message:
Sent: 02-22-2024 18:20
From: Floyd Gadd
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

I understand the Yamaha approach to differ from what Wim is advocating, in that it assumes some protrusion of the glide beyond the surface of the keyframe at the outset.  I recall reading of it somewhere, probably on this forum.

------------------------------
Floyd Gadd RPT
Regina SK
(306) 502-9103


Original Message:
Sent: 02-22-2024 18:13
From: Bill Ballard
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Of course, even bedding first and then setting keydip next, that dip will not be accurate except in the keybed where the glides were set. Bit I'm with Wim: aftertouch is far more important than dip. A good pianist will notice 10 mil inconsistencies far faster than than in dip (10 mils being a far greater portion of a .045" aftertouch than a .415" dip. Given that, aftertouch does need to be done in the keybed (unless of course you have the Grandworks System).

------------------------------
William Ballard RPT
WBPS
Saxtons River VT
802-869-9107

"Our lives contain a thousand springs
and dies if one be gone
Strange that a harp of a thousand strings
should keep in tune so long."
...........Dr. Watts, "The Continental Harmony,1774


Original Message:
Sent: 02-22-2024 16:52
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Yes Wim, that is exactly how I bed the action frame. I use Steve Brady's knocking technique that he writes about in his book, "Under the Lid." I start with all the bolts turned up and not touching the key bed. And I make sure it is bedded with dampers down, dampers up, and then with the shift pedal depressed with dampers down and up. 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com

Joe, 

Are saying that everything is wacked out simply by removing the action and putting it back in?  I feel like I'm missing something here. 

Peter Grey Piano Doctor 

I understand the Yamaha approach to differ from what Wim is advocating, in that it assumes some protrusion of the glide beyond the surface of the keyframe at the outset.  I recall reading of it somewhere, probably on this forum.

Of course, even bedding first and then setting keydip next, that dip will not be accurate except in the keybed where the glides were set. Bit I'm with Wim: aftertouch is far more important than dip. A good pianist will notice 10 mil inconsistencies far faster than than in dip (10 mils being a far greater portion of a .045" aftertouch than a .415" dip. Given that, aftertouch does need to be done in the keybed (unless of course you have the Grandworks System).

Yes Wim, that is exactly how I bed the action frame. I use Steve Brady's knocking technique that he writes about in his book, "Under the Lid." I start with all the bolts turned up and not touching the key bed. And I make sure it is bedded with dampers down, dampers up, and then with the shift pedal depressed with dampers down and up. 

Joe, 

Are saying that everything is wacked out simply by removing the action and putting it back in?  I feel like I'm missing something here. 

Peter Grey Piano Doctor 

I understand the Yamaha approach to differ from what Wim is advocating, in that it assumes some protrusion of the glide beyond the surface of the keyframe at the outset.  I recall reading of it somewhere, probably on this forum.

Of course, even bedding first and then setting keydip next, that dip will not be accurate except in the keybed where the glides were set. Bit I'm with Wim: aftertouch is far more important than dip. A good pianist will notice 10 mil inconsistencies far faster than than in dip (10 mils being a far greater portion of a .045" aftertouch than a .415" dip. Given that, aftertouch does need to be done in the keybed (unless of course you have the Grandworks System).

Yes Wim, that is exactly how I bed the action frame. I use Steve Brady's knocking technique that he writes about in his book, "Under the Lid." I start with all the bolts turned up and not touching the key bed. And I make sure it is bedded with dampers down, dampers up, and then with the shift pedal depressed with dampers down and up. 

I understand the Yamaha approach to differ from what Wim is advocating, in that it assumes some protrusion of the glide beyond the surface of the keyframe at the outset.  I recall reading of it somewhere, probably on this forum.

Of course, even bedding first and then setting keydip next, that dip will not be accurate except in the keybed where the glides were set. Bit I'm with Wim: aftertouch is far more important than dip. A good pianist will notice 10 mil inconsistencies far faster than than in dip (10 mils being a far greater portion of a .045" aftertouch than a .415" dip. Given that, aftertouch does need to be done in the keybed (unless of course you have the Grandworks System).

Yes Wim, that is exactly how I bed the action frame. I use Steve Brady's knocking technique that he writes about in his book, "Under the Lid." I start with all the bolts turned up and not touching the key bed. And I make sure it is bedded with dampers down, dampers up, and then with the shift pedal depressed with dampers down and up. 

You are absolutely right, Floyd. I learned this the hard way years ago. Yamaha's keyframes are quite flexible (and I believe this is the case with Samick too). If you bed them like a Steinway you will lose a significant amount of keydip and aftertouch. This needs to be mentioned frequently. 

The protocol for keyframe bedding at the Shigeru Kawai Seminar was to regulate with the glides all the way up to be absolutely certain they weren't affecting the regulation. Their' recommendation was to set them at the very end of the regulation and verify that they are not affecting keydip. 

Steinway, Kawai, and Baldwin I believe are all of the "stiff keyframe" variety.  

I understand the Yamaha approach to differ from what Wim is advocating, in that it assumes some protrusion of the glide beyond the surface of the keyframe at the outset.  I recall reading of it somewhere, probably on this forum.

Of course, even bedding first and then setting keydip next, that dip will not be accurate except in the keybed where the glides were set. Bit I'm with Wim: aftertouch is far more important than dip. A good pianist will notice 10 mil inconsistencies far faster than than in dip (10 mils being a far greater portion of a .045" aftertouch than a .415" dip. Given that, aftertouch does need to be done in the keybed (unless of course you have the Grandworks System).

Yes Wim, that is exactly how I bed the action frame. I use Steve Brady's knocking technique that he writes about in his book, "Under the Lid." I start with all the bolts turned up and not touching the key bed. And I make sure it is bedded with dampers down, dampers up, and then with the shift pedal depressed with dampers down and up. 

Joe -

  I sensed some basic confusion in your original  question and wondered how you might re-frame (NPI) it, after the numerous comments you received, but, while waiting, I had a few followup questions for you-

• why would you be setting keydip out of the piano, on a caddy that can't possibly have the same controlled adjustability as something like Chris Brown's set up accomplishes?  (note: there HAD to be a reason he devoted so many brain cells to the project)
• you say the key dip changes every time you re-bed the keyframe.  Others have already questioned this.  Of course key dip will change if you alter the bedding, but the question is: why are you 're' bedding, if your painstaking effort was successful to begin with.  I think your focus needs to remain with the reliablity of the bedding process and the applicability of that process to the given manufacturer.  As Horace Greeley further described, even within Steinway, the methods of construction have changed over time, requiring modifications in approach.
• from my own experience (specific to Steinway), I'll share these marginally useful observations:
  
  • check shape of keybed with straight edge for any obvious anomalies
  • check underside of keyframe, front to back, along its entire length for the presence (or absence) of 'crown', which is part of Steinway design.  If the frame has collapsed (straight edge contacts balance rail wood) it will be impossible to reliably bed using the traditional 'tap' method, and will potentially create other problems such as excess shift friction
  • BACK  RAIL!!! I admit it. I dislike them.  I tend to avoid them, ususally to my detriment.  While this may be one of those steps that Bill Ballard referenced as not having a significant impact on keydip, the problems associated with poorly fit back rail can be subtle and persistent, especially if there is inadequate postive pressure from 'dogs' (or dags?).
  • To add to the confusion, I would re-pose a question to Horace (or anyone else who knows) that I think I asked some years ago: I thought I remember an 'old-timer' describing the intentional flexing of the frame with extra pressure from the glide adjustment to increase the stiffness of the frame, to reflect energy.  This would require that the dogs/dags exert positive contact to prevent the back rail from lifting, and not be excessive enough to create shift drag or squeaks.  Anyone know if I made this up?

Sorry about the confusion my initial question caused. Here is a clarification.

Here is my current protocol for bedding:

1) I bed the action in the piano using the knock method with the side bocks tightened down. I make sure the action is bedded properly with sustain pedal up, then down, then with shift pedal activated while pressing up and down with the sustain pedal. So, I bed the action frame in four different positions. 1-Sustain disengaged, 2-Sustain pedal engaged, 3-Shift pedal engaged with sustain pedal disengaged, 4-Shift pedal engaged with sustain pedal disengaged.

2) I then set key dip on sample keys up and down the keyboard while it is still in the piano.

3) I take the action out of the piano and put it on the Edwards dolly. I do not touch the glide bolts, but use the Edwars dolly adjustments to match the exact key dip that was set in the piano for each of the sample notes I am regulating. Sometimes I will take the top action off in order to install a capstan boat to figure out how much it needs to be moved if that is a problem. Then I reinstall the top action.

4) I then put the action back into the piano, install and screw down the side blocks and let it sit for a while. The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem.

All your comments have been helpful to think about this issue, and makes me think of the questions below: 

?- I do wonder if using the WNG bedding gauge instead of the knock bedding method would be a more accurate way of bedding the action.

?- I also wonder if on some pianos taking the action in and out of the piano can actually minutely shift the position of the wood joints that hold the action frame together. If this is the case then the bedding will always change when the action is removed and put back into the piano. The piano I am working on is from 1922, so I would not be surprised if the wooden key frame joints have deteriorated. A remedy for this would be to take apart the action frame on older pianos and reglue all the joints. This is something that I have never thought of before, but it might actually be something that would help with action frame stability on old pianos. Do some piano rebuilders do this? Take apart old action frames and reglue them before doing their action work? 

Joe -

  I sensed some basic confusion in your original  question and wondered how you might re-frame (NPI) it, after the numerous comments you received, but, while waiting, I had a few followup questions for you-

• why would you be setting keydip out of the piano, on a caddy that can't possibly have the same controlled adjustability as something like Chris Brown's set up accomplishes?  (note: there HAD to be a reason he devoted so many brain cells to the project)
• you say the key dip changes every time you re-bed the keyframe.  Others have already questioned this.  Of course key dip will change if you alter the bedding, but the question is: why are you 're' bedding, if your painstaking effort was successful to begin with.  I think your focus needs to remain with the reliablity of the bedding process and the applicability of that process to the given manufacturer.  As Horace Greeley further described, even within Steinway, the methods of construction have changed over time, requiring modifications in approach.
• from my own experience (specific to Steinway), I'll share these marginally useful observations:
  
  • check shape of keybed with straight edge for any obvious anomalies
  • check underside of keyframe, front to back, along its entire length for the presence (or absence) of 'crown', which is part of Steinway design.  If the frame has collapsed (straight edge contacts balance rail wood) it will be impossible to reliably bed using the traditional 'tap' method, and will potentially create other problems such as excess shift friction
  • BACK  RAIL!!! I admit it. I dislike them.  I tend to avoid them, ususally to my detriment.  While this may be one of those steps that Bill Ballard referenced as not having a significant impact on keydip, the problems associated with poorly fit back rail can be subtle and persistent, especially if there is inadequate postive pressure from 'dogs' (or dags?).
  • To add to the confusion, I would re-pose a question to Horace (or anyone else who knows) that I think I asked some years ago: I thought I remember an 'old-timer' describing the intentional flexing of the frame with extra pressure from the glide adjustment to increase the stiffness of the frame, to reflect energy.  This would require that the dogs/dags exert positive contact to prevent the back rail from lifting, and not be excessive enough to create shift drag or squeaks.  Anyone know if I made this up?

Hi Joe -

Thanks for playing along.  I have a few more thoughts on your enumerated points:

This comment strikes me as key -

"The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem."

What do you mean, precisely, that "the bedding is off"?  Is it knocking?  Then, once you correct it, is the dip still incorrect?  By how much?  Does this happen all the time or only sometimes? It's possible to imagine that, with a 'lightly' bedded frame, changes in humidity can produce such symptoms.  Also, we didn't establish whether this happens with particular manufacturers or across brands.  

 A potential variable in the 'knock' method, even without the problem of a possible absence of keyframe crown that I previously mentioned, is the actual amount of pressure you chose to have being exerted by the glides.  We gauge this by assessing how much force we have to employ in lifting the action to induce the knock. 

You thought about the possibility of the keyframe members having become unglued, which is worth checking at the outset, but most frames (I think) are secured with screws.  On the other hand, there's always potential for some effect when you disassemble and reassemble the top action from the frame.

Sorry about the confusion my initial question caused. Here is a clarification.

Here is my current protocol for bedding:

1) I bed the action in the piano using the knock method with the side bocks tightened down. I make sure the action is bedded properly with sustain pedal up, then down, then with shift pedal activated while pressing up and down with the sustain pedal. So, I bed the action frame in four different positions. 1-Sustain disengaged, 2-Sustain pedal engaged, 3-Shift pedal engaged with sustain pedal disengaged, 4-Shift pedal engaged with sustain pedal disengaged.

2) I then set key dip on sample keys up and down the keyboard while it is still in the piano.

3) I take the action out of the piano and put it on the Edwards dolly. I do not touch the glide bolts, but use the Edwars dolly adjustments to match the exact key dip that was set in the piano for each of the sample notes I am regulating. Sometimes I will take the top action off in order to install a capstan boat to figure out how much it needs to be moved if that is a problem. Then I reinstall the top action.

4) I then put the action back into the piano, install and screw down the side blocks and let it sit for a while. The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem.

All your comments have been helpful to think about this issue, and makes me think of the questions below: 

?- I do wonder if using the WNG bedding gauge instead of the knock bedding method would be a more accurate way of bedding the action.

?- I also wonder if on some pianos taking the action in and out of the piano can actually minutely shift the position of the wood joints that hold the action frame together. If this is the case then the bedding will always change when the action is removed and put back into the piano. The piano I am working on is from 1922, so I would not be surprised if the wooden key frame joints have deteriorated. A remedy for this would be to take apart the action frame on older pianos and reglue all the joints. This is something that I have never thought of before, but it might actually be something that would help with action frame stability on old pianos. Do some piano rebuilders do this? Take apart old action frames and reglue them before doing their action work? 

Joe -

  I sensed some basic confusion in your original  question and wondered how you might re-frame (NPI) it, after the numerous comments you received, but, while waiting, I had a few followup questions for you-

• why would you be setting keydip out of the piano, on a caddy that can't possibly have the same controlled adjustability as something like Chris Brown's set up accomplishes?  (note: there HAD to be a reason he devoted so many brain cells to the project)
• you say the key dip changes every time you re-bed the keyframe.  Others have already questioned this.  Of course key dip will change if you alter the bedding, but the question is: why are you 're' bedding, if your painstaking effort was successful to begin with.  I think your focus needs to remain with the reliablity of the bedding process and the applicability of that process to the given manufacturer.  As Horace Greeley further described, even within Steinway, the methods of construction have changed over time, requiring modifications in approach.
• from my own experience (specific to Steinway), I'll share these marginally useful observations:
  
  • check shape of keybed with straight edge for any obvious anomalies
  • check underside of keyframe, front to back, along its entire length for the presence (or absence) of 'crown', which is part of Steinway design.  If the frame has collapsed (straight edge contacts balance rail wood) it will be impossible to reliably bed using the traditional 'tap' method, and will potentially create other problems such as excess shift friction
  • BACK  RAIL!!! I admit it. I dislike them.  I tend to avoid them, ususally to my detriment.  While this may be one of those steps that Bill Ballard referenced as not having a significant impact on keydip, the problems associated with poorly fit back rail can be subtle and persistent, especially if there is inadequate postive pressure from 'dogs' (or dags?).
  • To add to the confusion, I would re-pose a question to Horace (or anyone else who knows) that I think I asked some years ago: I thought I remember an 'old-timer' describing the intentional flexing of the frame with extra pressure from the glide adjustment to increase the stiffness of the frame, to reflect energy.  This would require that the dogs/dags exert positive contact to prevent the back rail from lifting, and not be excessive enough to create shift drag or squeaks.  Anyone know if I made this up?

In addition to David's question(s) just how much has the dip spec changed in this scenario? 

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com
------------------------------


Original Message:
Sent: 02-26-2024 00:55
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Hi Joe -

Thanks for playing along.  I have a few more thoughts on your enumerated points:

This comment strikes me as key -

"The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem."

What do you mean, precisely, that "the bedding is off"?  Is it knocking?  Then, once you correct it, is the dip still incorrect?  By how much?  Does this happen all the time or only sometimes? It's possible to imagine that, with a 'lightly' bedded frame, changes in humidity can produce such symptoms.  Also, we didn't establish whether this happens with particular manufacturers or across brands.  

 A potential variable in the 'knock' method, even without the problem of a possible absence of keyframe crown that I previously mentioned, is the actual amount of pressure you chose to have being exerted by the glides.  We gauge this by assessing how much force we have to employ in lifting the action to induce the knock. 

You thought about the possibility of the keyframe members having become unglued, which is worth checking at the outset, but most frames (I think) are secured with screws.  On the other hand, there's always potential for some effect when you disassemble and reassemble the top action from the frame.

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625


Original Message:
Sent: 02-25-2024 17:08
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Sorry about the confusion my initial question caused. Here is a clarification.

Here is my current protocol for bedding:

1) I bed the action in the piano using the knock method with the side bocks tightened down. I make sure the action is bedded properly with sustain pedal up, then down, then with shift pedal activated while pressing up and down with the sustain pedal. So, I bed the action frame in four different positions. 1-Sustain disengaged, 2-Sustain pedal engaged, 3-Shift pedal engaged with sustain pedal disengaged, 4-Shift pedal engaged with sustain pedal disengaged.

2) I then set key dip on sample keys up and down the keyboard while it is still in the piano.

3) I take the action out of the piano and put it on the Edwards dolly. I do not touch the glide bolts, but use the Edwars dolly adjustments to match the exact key dip that was set in the piano for each of the sample notes I am regulating. Sometimes I will take the top action off in order to install a capstan boat to figure out how much it needs to be moved if that is a problem. Then I reinstall the top action.

4) I then put the action back into the piano, install and screw down the side blocks and let it sit for a while. The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem.

All your comments have been helpful to think about this issue, and makes me think of the questions below: 

?- I do wonder if using the WNG bedding gauge instead of the knock bedding method would be a more accurate way of bedding the action.

?- I also wonder if on some pianos taking the action in and out of the piano can actually minutely shift the position of the wood joints that hold the action frame together. If this is the case then the bedding will always change when the action is removed and put back into the piano. The piano I am working on is from 1922, so I would not be surprised if the wooden key frame joints have deteriorated. A remedy for this would be to take apart the action frame on older pianos and reglue all the joints. This is something that I have never thought of before, but it might actually be something that would help with action frame stability on old pianos. Do some piano rebuilders do this? Take apart old action frames and reglue them before doing their action work? 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-25-2024 13:43
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Joe -

  I sensed some basic confusion in your original  question and wondered how you might re-frame (NPI) it, after the numerous comments you received, but, while waiting, I had a few followup questions for you-

• why would you be setting keydip out of the piano, on a caddy that can't possibly have the same controlled adjustability as something like Chris Brown's set up accomplishes?  (note: there HAD to be a reason he devoted so many brain cells to the project)
• you say the key dip changes every time you re-bed the keyframe.  Others have already questioned this.  Of course key dip will change if you alter the bedding, but the question is: why are you 're' bedding, if your painstaking effort was successful to begin with.  I think your focus needs to remain with the reliablity of the bedding process and the applicability of that process to the given manufacturer.  As Horace Greeley further described, even within Steinway, the methods of construction have changed over time, requiring modifications in approach.
• from my own experience (specific to Steinway), I'll share these marginally useful observations:
  
  • check shape of keybed with straight edge for any obvious anomalies
  • check underside of keyframe, front to back, along its entire length for the presence (or absence) of 'crown', which is part of Steinway design.  If the frame has collapsed (straight edge contacts balance rail wood) it will be impossible to reliably bed using the traditional 'tap' method, and will potentially create other problems such as excess shift friction
  • BACK  RAIL!!! I admit it. I dislike them.  I tend to avoid them, ususally to my detriment.  While this may be one of those steps that Bill Ballard referenced as not having a significant impact on keydip, the problems associated with poorly fit back rail can be subtle and persistent, especially if there is inadequate postive pressure from 'dogs' (or dags?).
  • To add to the confusion, I would re-pose a question to Horace (or anyone else who knows) that I think I asked some years ago: I thought I remember an 'old-timer' describing the intentional flexing of the frame with extra pressure from the glide adjustment to increase the stiffness of the frame, to reflect energy.  This would require that the dogs/dags exert positive contact to prevent the back rail from lifting, and not be excessive enough to create shift drag or squeaks.  Anyone know if I made this up?

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625

Yes, David, when I say the bedding is off after putting the action back into the piano after having it on the Edwards Trolley, I mean that it is knocking. Then  after I re-bed the action the Dip has changed. I would have to keep better track of how much the Dip changes, but it is obvious when I feel it on the Dip Block. I would estimate the change to be around a .006 to .012, but I am not exactly sure. I will pay better attention to it and write down when this happens. 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com
------------------------------


Original Message:
Sent: 02-26-2024 09:20
From: Peter Grey
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

In addition to David's question(s) just how much has the dip spec changed in this scenario? 

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com


Original Message:
Sent: 02-26-2024 00:55
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Hi Joe -

Thanks for playing along.  I have a few more thoughts on your enumerated points:

This comment strikes me as key -

"The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem."

What do you mean, precisely, that "the bedding is off"?  Is it knocking?  Then, once you correct it, is the dip still incorrect?  By how much?  Does this happen all the time or only sometimes? It's possible to imagine that, with a 'lightly' bedded frame, changes in humidity can produce such symptoms.  Also, we didn't establish whether this happens with particular manufacturers or across brands.  

 A potential variable in the 'knock' method, even without the problem of a possible absence of keyframe crown that I previously mentioned, is the actual amount of pressure you chose to have being exerted by the glides.  We gauge this by assessing how much force we have to employ in lifting the action to induce the knock. 

You thought about the possibility of the keyframe members having become unglued, which is worth checking at the outset, but most frames (I think) are secured with screws.  On the other hand, there's always potential for some effect when you disassemble and reassemble the top action from the frame.

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625


Original Message:
Sent: 02-25-2024 17:08
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Sorry about the confusion my initial question caused. Here is a clarification.

Here is my current protocol for bedding:

1) I bed the action in the piano using the knock method with the side bocks tightened down. I make sure the action is bedded properly with sustain pedal up, then down, then with shift pedal activated while pressing up and down with the sustain pedal. So, I bed the action frame in four different positions. 1-Sustain disengaged, 2-Sustain pedal engaged, 3-Shift pedal engaged with sustain pedal disengaged, 4-Shift pedal engaged with sustain pedal disengaged.

2) I then set key dip on sample keys up and down the keyboard while it is still in the piano.

3) I take the action out of the piano and put it on the Edwards dolly. I do not touch the glide bolts, but use the Edwars dolly adjustments to match the exact key dip that was set in the piano for each of the sample notes I am regulating. Sometimes I will take the top action off in order to install a capstan boat to figure out how much it needs to be moved if that is a problem. Then I reinstall the top action.

4) I then put the action back into the piano, install and screw down the side blocks and let it sit for a while. The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem.

All your comments have been helpful to think about this issue, and makes me think of the questions below: 

?- I do wonder if using the WNG bedding gauge instead of the knock bedding method would be a more accurate way of bedding the action.

?- I also wonder if on some pianos taking the action in and out of the piano can actually minutely shift the position of the wood joints that hold the action frame together. If this is the case then the bedding will always change when the action is removed and put back into the piano. The piano I am working on is from 1922, so I would not be surprised if the wooden key frame joints have deteriorated. A remedy for this would be to take apart the action frame on older pianos and reglue all the joints. This is something that I have never thought of before, but it might actually be something that would help with action frame stability on old pianos. Do some piano rebuilders do this? Take apart old action frames and reglue them before doing their action work? 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-25-2024 13:43
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Joe -

  I sensed some basic confusion in your original  question and wondered how you might re-frame (NPI) it, after the numerous comments you received, but, while waiting, I had a few followup questions for you-

• why would you be setting keydip out of the piano, on a caddy that can't possibly have the same controlled adjustability as something like Chris Brown's set up accomplishes?  (note: there HAD to be a reason he devoted so many brain cells to the project)
• you say the key dip changes every time you re-bed the keyframe.  Others have already questioned this.  Of course key dip will change if you alter the bedding, but the question is: why are you 're' bedding, if your painstaking effort was successful to begin with.  I think your focus needs to remain with the reliablity of the bedding process and the applicability of that process to the given manufacturer.  As Horace Greeley further described, even within Steinway, the methods of construction have changed over time, requiring modifications in approach.
• from my own experience (specific to Steinway), I'll share these marginally useful observations:
  
  • check shape of keybed with straight edge for any obvious anomalies
  • check underside of keyframe, front to back, along its entire length for the presence (or absence) of 'crown', which is part of Steinway design.  If the frame has collapsed (straight edge contacts balance rail wood) it will be impossible to reliably bed using the traditional 'tap' method, and will potentially create other problems such as excess shift friction
  • BACK  RAIL!!! I admit it. I dislike them.  I tend to avoid them, ususally to my detriment.  While this may be one of those steps that Bill Ballard referenced as not having a significant impact on keydip, the problems associated with poorly fit back rail can be subtle and persistent, especially if there is inadequate postive pressure from 'dogs' (or dags?).
  • To add to the confusion, I would re-pose a question to Horace (or anyone else who knows) that I think I asked some years ago: I thought I remember an 'old-timer' describing the intentional flexing of the frame with extra pressure from the glide adjustment to increase the stiffness of the frame, to reflect energy.  This would require that the dogs/dags exert positive contact to prevent the back rail from lifting, and not be excessive enough to create shift drag or squeaks.  Anyone know if I made this up?

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625

Joe,

Knocking everywhere? Or just one or two studs knocking ever so slightly? 

Peter Grey Piano Doctor 

Yes, David, when I say the bedding is off after putting the action back into the piano after having it on the Edwards Trolley, I mean that it is knocking. Then  after I re-bed the action the Dip has changed. I would have to keep better track of how much the Dip changes, but it is obvious when I feel it on the Dip Block. I would estimate the change to be around a .006 to .012, but I am not exactly sure. I will pay better attention to it and write down when this happens. 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-26-2024 09:20
From: Peter Grey
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

In addition to David's question(s) just how much has the dip spec changed in this scenario? 

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com


Original Message:
Sent: 02-26-2024 00:55
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Hi Joe -

Thanks for playing along.  I have a few more thoughts on your enumerated points:

This comment strikes me as key -

"The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem."

What do you mean, precisely, that "the bedding is off"?  Is it knocking?  Then, once you correct it, is the dip still incorrect?  By how much?  Does this happen all the time or only sometimes? It's possible to imagine that, with a 'lightly' bedded frame, changes in humidity can produce such symptoms.  Also, we didn't establish whether this happens with particular manufacturers or across brands.  

 A potential variable in the 'knock' method, even without the problem of a possible absence of keyframe crown that I previously mentioned, is the actual amount of pressure you chose to have being exerted by the glides.  We gauge this by assessing how much force we have to employ in lifting the action to induce the knock. 

You thought about the possibility of the keyframe members having become unglued, which is worth checking at the outset, but most frames (I think) are secured with screws.  On the other hand, there's always potential for some effect when you disassemble and reassemble the top action from the frame.

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625


Original Message:
Sent: 02-25-2024 17:08
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Sorry about the confusion my initial question caused. Here is a clarification.

Here is my current protocol for bedding:

1) I bed the action in the piano using the knock method with the side bocks tightened down. I make sure the action is bedded properly with sustain pedal up, then down, then with shift pedal activated while pressing up and down with the sustain pedal. So, I bed the action frame in four different positions. 1-Sustain disengaged, 2-Sustain pedal engaged, 3-Shift pedal engaged with sustain pedal disengaged, 4-Shift pedal engaged with sustain pedal disengaged.

2) I then set key dip on sample keys up and down the keyboard while it is still in the piano.

3) I take the action out of the piano and put it on the Edwards dolly. I do not touch the glide bolts, but use the Edwars dolly adjustments to match the exact key dip that was set in the piano for each of the sample notes I am regulating. Sometimes I will take the top action off in order to install a capstan boat to figure out how much it needs to be moved if that is a problem. Then I reinstall the top action.

4) I then put the action back into the piano, install and screw down the side blocks and let it sit for a while. The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem.

All your comments have been helpful to think about this issue, and makes me think of the questions below: 

?- I do wonder if using the WNG bedding gauge instead of the knock bedding method would be a more accurate way of bedding the action.

?- I also wonder if on some pianos taking the action in and out of the piano can actually minutely shift the position of the wood joints that hold the action frame together. If this is the case then the bedding will always change when the action is removed and put back into the piano. The piano I am working on is from 1922, so I would not be surprised if the wooden key frame joints have deteriorated. A remedy for this would be to take apart the action frame on older pianos and reglue all the joints. This is something that I have never thought of before, but it might actually be something that would help with action frame stability on old pianos. Do some piano rebuilders do this? Take apart old action frames and reglue them before doing their action work? 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-25-2024 13:43
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Joe -

  I sensed some basic confusion in your original  question and wondered how you might re-frame (NPI) it, after the numerous comments you received, but, while waiting, I had a few followup questions for you-

• why would you be setting keydip out of the piano, on a caddy that can't possibly have the same controlled adjustability as something like Chris Brown's set up accomplishes?  (note: there HAD to be a reason he devoted so many brain cells to the project)
• you say the key dip changes every time you re-bed the keyframe.  Others have already questioned this.  Of course key dip will change if you alter the bedding, but the question is: why are you 're' bedding, if your painstaking effort was successful to begin with.  I think your focus needs to remain with the reliablity of the bedding process and the applicability of that process to the given manufacturer.  As Horace Greeley further described, even within Steinway, the methods of construction have changed over time, requiring modifications in approach.
• from my own experience (specific to Steinway), I'll share these marginally useful observations:
  
  • check shape of keybed with straight edge for any obvious anomalies
  • check underside of keyframe, front to back, along its entire length for the presence (or absence) of 'crown', which is part of Steinway design.  If the frame has collapsed (straight edge contacts balance rail wood) it will be impossible to reliably bed using the traditional 'tap' method, and will potentially create other problems such as excess shift friction
  • BACK  RAIL!!! I admit it. I dislike them.  I tend to avoid them, ususally to my detriment.  While this may be one of those steps that Bill Ballard referenced as not having a significant impact on keydip, the problems associated with poorly fit back rail can be subtle and persistent, especially if there is inadequate postive pressure from 'dogs' (or dags?).
  • To add to the confusion, I would re-pose a question to Horace (or anyone else who knows) that I think I asked some years ago: I thought I remember an 'old-timer' describing the intentional flexing of the frame with extra pressure from the glide adjustment to increase the stiffness of the frame, to reflect energy.  This would require that the dogs/dags exert positive contact to prevent the back rail from lifting, and not be excessive enough to create shift drag or squeaks.  Anyone know if I made this up?

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625

Peter, Slight knocking, usually on the first and second bolt from the left, bass side of the piano.

Joe

Joe,

Knocking everywhere? Or just one or two studs knocking ever so slightly? 

Peter Grey Piano Doctor 

Yes, David, when I say the bedding is off after putting the action back into the piano after having it on the Edwards Trolley, I mean that it is knocking. Then  after I re-bed the action the Dip has changed. I would have to keep better track of how much the Dip changes, but it is obvious when I feel it on the Dip Block. I would estimate the change to be around a .006 to .012, but I am not exactly sure. I will pay better attention to it and write down when this happens. 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-26-2024 09:20
From: Peter Grey
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

In addition to David's question(s) just how much has the dip spec changed in this scenario? 

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com


Original Message:
Sent: 02-26-2024 00:55
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Hi Joe -

Thanks for playing along.  I have a few more thoughts on your enumerated points:

This comment strikes me as key -

"The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem."

What do you mean, precisely, that "the bedding is off"?  Is it knocking?  Then, once you correct it, is the dip still incorrect?  By how much?  Does this happen all the time or only sometimes? It's possible to imagine that, with a 'lightly' bedded frame, changes in humidity can produce such symptoms.  Also, we didn't establish whether this happens with particular manufacturers or across brands.  

 A potential variable in the 'knock' method, even without the problem of a possible absence of keyframe crown that I previously mentioned, is the actual amount of pressure you chose to have being exerted by the glides.  We gauge this by assessing how much force we have to employ in lifting the action to induce the knock. 

You thought about the possibility of the keyframe members having become unglued, which is worth checking at the outset, but most frames (I think) are secured with screws.  On the other hand, there's always potential for some effect when you disassemble and reassemble the top action from the frame.

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625


Original Message:
Sent: 02-25-2024 17:08
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Sorry about the confusion my initial question caused. Here is a clarification.

Here is my current protocol for bedding:

1) I bed the action in the piano using the knock method with the side bocks tightened down. I make sure the action is bedded properly with sustain pedal up, then down, then with shift pedal activated while pressing up and down with the sustain pedal. So, I bed the action frame in four different positions. 1-Sustain disengaged, 2-Sustain pedal engaged, 3-Shift pedal engaged with sustain pedal disengaged, 4-Shift pedal engaged with sustain pedal disengaged.

2) I then set key dip on sample keys up and down the keyboard while it is still in the piano.

3) I take the action out of the piano and put it on the Edwards dolly. I do not touch the glide bolts, but use the Edwars dolly adjustments to match the exact key dip that was set in the piano for each of the sample notes I am regulating. Sometimes I will take the top action off in order to install a capstan boat to figure out how much it needs to be moved if that is a problem. Then I reinstall the top action.

4) I then put the action back into the piano, install and screw down the side blocks and let it sit for a while. The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem.

All your comments have been helpful to think about this issue, and makes me think of the questions below: 

?- I do wonder if using the WNG bedding gauge instead of the knock bedding method would be a more accurate way of bedding the action.

?- I also wonder if on some pianos taking the action in and out of the piano can actually minutely shift the position of the wood joints that hold the action frame together. If this is the case then the bedding will always change when the action is removed and put back into the piano. The piano I am working on is from 1922, so I would not be surprised if the wooden key frame joints have deteriorated. A remedy for this would be to take apart the action frame on older pianos and reglue all the joints. This is something that I have never thought of before, but it might actually be something that would help with action frame stability on old pianos. Do some piano rebuilders do this? Take apart old action frames and reglue them before doing their action work? 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-25-2024 13:43
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Joe -

  I sensed some basic confusion in your original  question and wondered how you might re-frame (NPI) it, after the numerous comments you received, but, while waiting, I had a few followup questions for you-

• why would you be setting keydip out of the piano, on a caddy that can't possibly have the same controlled adjustability as something like Chris Brown's set up accomplishes?  (note: there HAD to be a reason he devoted so many brain cells to the project)
• you say the key dip changes every time you re-bed the keyframe.  Others have already questioned this.  Of course key dip will change if you alter the bedding, but the question is: why are you 're' bedding, if your painstaking effort was successful to begin with.  I think your focus needs to remain with the reliablity of the bedding process and the applicability of that process to the given manufacturer.  As Horace Greeley further described, even within Steinway, the methods of construction have changed over time, requiring modifications in approach.
• from my own experience (specific to Steinway), I'll share these marginally useful observations:
  
  • check shape of keybed with straight edge for any obvious anomalies
  • check underside of keyframe, front to back, along its entire length for the presence (or absence) of 'crown', which is part of Steinway design.  If the frame has collapsed (straight edge contacts balance rail wood) it will be impossible to reliably bed using the traditional 'tap' method, and will potentially create other problems such as excess shift friction
  • BACK  RAIL!!! I admit it. I dislike them.  I tend to avoid them, ususally to my detriment.  While this may be one of those steps that Bill Ballard referenced as not having a significant impact on keydip, the problems associated with poorly fit back rail can be subtle and persistent, especially if there is inadequate postive pressure from 'dogs' (or dags?).
  • To add to the confusion, I would re-pose a question to Horace (or anyone else who knows) that I think I asked some years ago: I thought I remember an 'old-timer' describing the intentional flexing of the frame with extra pressure from the glide adjustment to increase the stiffness of the frame, to reflect energy.  This would require that the dogs/dags exert positive contact to prevent the back rail from lifting, and not be excessive enough to create shift drag or squeaks.  Anyone know if I made this up?

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625

Are all the stack screws absolutely tight?  Does the stack sit squarely on the feet of the keyframe?  Is the hammer rail straight when it's screwed down?   I suggest that the stack is influencing the flexing of the keyframe so that when you put it in and take it it's changing the bedding.

Peter, Slight knocking, usually on the first and second bolt from the left, bass side of the piano.

Joe

Joe,

Knocking everywhere? Or just one or two studs knocking ever so slightly? 

Peter Grey Piano Doctor 

Yes, David, when I say the bedding is off after putting the action back into the piano after having it on the Edwards Trolley, I mean that it is knocking. Then  after I re-bed the action the Dip has changed. I would have to keep better track of how much the Dip changes, but it is obvious when I feel it on the Dip Block. I would estimate the change to be around a .006 to .012, but I am not exactly sure. I will pay better attention to it and write down when this happens. 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-26-2024 09:20
From: Peter Grey
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

In addition to David's question(s) just how much has the dip spec changed in this scenario? 

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com


Original Message:
Sent: 02-26-2024 00:55
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Hi Joe -

Thanks for playing along.  I have a few more thoughts on your enumerated points:

This comment strikes me as key -

"The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem."

What do you mean, precisely, that "the bedding is off"?  Is it knocking?  Then, once you correct it, is the dip still incorrect?  By how much?  Does this happen all the time or only sometimes? It's possible to imagine that, with a 'lightly' bedded frame, changes in humidity can produce such symptoms.  Also, we didn't establish whether this happens with particular manufacturers or across brands.  

 A potential variable in the 'knock' method, even without the problem of a possible absence of keyframe crown that I previously mentioned, is the actual amount of pressure you chose to have being exerted by the glides.  We gauge this by assessing how much force we have to employ in lifting the action to induce the knock. 

You thought about the possibility of the keyframe members having become unglued, which is worth checking at the outset, but most frames (I think) are secured with screws.  On the other hand, there's always potential for some effect when you disassemble and reassemble the top action from the frame.

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625


Original Message:
Sent: 02-25-2024 17:08
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Sorry about the confusion my initial question caused. Here is a clarification.

Here is my current protocol for bedding:

1) I bed the action in the piano using the knock method with the side bocks tightened down. I make sure the action is bedded properly with sustain pedal up, then down, then with shift pedal activated while pressing up and down with the sustain pedal. So, I bed the action frame in four different positions. 1-Sustain disengaged, 2-Sustain pedal engaged, 3-Shift pedal engaged with sustain pedal disengaged, 4-Shift pedal engaged with sustain pedal disengaged.

2) I then set key dip on sample keys up and down the keyboard while it is still in the piano.

3) I take the action out of the piano and put it on the Edwards dolly. I do not touch the glide bolts, but use the Edwars dolly adjustments to match the exact key dip that was set in the piano for each of the sample notes I am regulating. Sometimes I will take the top action off in order to install a capstan boat to figure out how much it needs to be moved if that is a problem. Then I reinstall the top action.

4) I then put the action back into the piano, install and screw down the side blocks and let it sit for a while. The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem.

All your comments have been helpful to think about this issue, and makes me think of the questions below: 

?- I do wonder if using the WNG bedding gauge instead of the knock bedding method would be a more accurate way of bedding the action.

?- I also wonder if on some pianos taking the action in and out of the piano can actually minutely shift the position of the wood joints that hold the action frame together. If this is the case then the bedding will always change when the action is removed and put back into the piano. The piano I am working on is from 1922, so I would not be surprised if the wooden key frame joints have deteriorated. A remedy for this would be to take apart the action frame on older pianos and reglue all the joints. This is something that I have never thought of before, but it might actually be something that would help with action frame stability on old pianos. Do some piano rebuilders do this? Take apart old action frames and reglue them before doing their action work? 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-25-2024 13:43
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Joe -

  I sensed some basic confusion in your original  question and wondered how you might re-frame (NPI) it, after the numerous comments you received, but, while waiting, I had a few followup questions for you-

• why would you be setting keydip out of the piano, on a caddy that can't possibly have the same controlled adjustability as something like Chris Brown's set up accomplishes?  (note: there HAD to be a reason he devoted so many brain cells to the project)
• you say the key dip changes every time you re-bed the keyframe.  Others have already questioned this.  Of course key dip will change if you alter the bedding, but the question is: why are you 're' bedding, if your painstaking effort was successful to begin with.  I think your focus needs to remain with the reliablity of the bedding process and the applicability of that process to the given manufacturer.  As Horace Greeley further described, even within Steinway, the methods of construction have changed over time, requiring modifications in approach.
• from my own experience (specific to Steinway), I'll share these marginally useful observations:
  
  • check shape of keybed with straight edge for any obvious anomalies
  • check underside of keyframe, front to back, along its entire length for the presence (or absence) of 'crown', which is part of Steinway design.  If the frame has collapsed (straight edge contacts balance rail wood) it will be impossible to reliably bed using the traditional 'tap' method, and will potentially create other problems such as excess shift friction
  • BACK  RAIL!!! I admit it. I dislike them.  I tend to avoid them, ususally to my detriment.  While this may be one of those steps that Bill Ballard referenced as not having a significant impact on keydip, the problems associated with poorly fit back rail can be subtle and persistent, especially if there is inadequate postive pressure from 'dogs' (or dags?).
  • To add to the confusion, I would re-pose a question to Horace (or anyone else who knows) that I think I asked some years ago: I thought I remember an 'old-timer' describing the intentional flexing of the frame with extra pressure from the glide adjustment to increase the stiffness of the frame, to reflect energy.  This would require that the dogs/dags exert positive contact to prevent the back rail from lifting, and not be excessive enough to create shift drag or squeaks.  Anyone know if I made this up?

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625

Hi Paul, Yes, all stack screws are tight. If any become loose I put West Systems epoxy in the hole and re-thread it to create a very tight screw fit. And yes, the stack feet are all sitting squarely on the frame. I am meticulous about these things. In addition, I always let the stack sit in the piano for hours or overnight after putting it back into the piano in order to let the action frame settle and adjust to the key bed. 

What I am wondering is, are other techs having this same experience as I am having, or is it not an issue? Or do you all notice changes in the dip when you re-bed the action, but don't worry about it?

Are all the stack screws absolutely tight?  Does the stack sit squarely on the feet of the keyframe?  Is the hammer rail straight when it's screwed down?   I suggest that the stack is influencing the flexing of the keyframe so that when you put it in and take it it's changing the bedding.

Peter, Slight knocking, usually on the first and second bolt from the left, bass side of the piano.

Joe

Joe,

Knocking everywhere? Or just one or two studs knocking ever so slightly? 

Peter Grey Piano Doctor 

Yes, David, when I say the bedding is off after putting the action back into the piano after having it on the Edwards Trolley, I mean that it is knocking. Then  after I re-bed the action the Dip has changed. I would have to keep better track of how much the Dip changes, but it is obvious when I feel it on the Dip Block. I would estimate the change to be around a .006 to .012, but I am not exactly sure. I will pay better attention to it and write down when this happens. 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-26-2024 09:20
From: Peter Grey
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

In addition to David's question(s) just how much has the dip spec changed in this scenario? 

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com


Original Message:
Sent: 02-26-2024 00:55
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Hi Joe -

Thanks for playing along.  I have a few more thoughts on your enumerated points:

This comment strikes me as key -

"The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem."

What do you mean, precisely, that "the bedding is off"?  Is it knocking?  Then, once you correct it, is the dip still incorrect?  By how much?  Does this happen all the time or only sometimes? It's possible to imagine that, with a 'lightly' bedded frame, changes in humidity can produce such symptoms.  Also, we didn't establish whether this happens with particular manufacturers or across brands.  

 A potential variable in the 'knock' method, even without the problem of a possible absence of keyframe crown that I previously mentioned, is the actual amount of pressure you chose to have being exerted by the glides.  We gauge this by assessing how much force we have to employ in lifting the action to induce the knock. 

You thought about the possibility of the keyframe members having become unglued, which is worth checking at the outset, but most frames (I think) are secured with screws.  On the other hand, there's always potential for some effect when you disassemble and reassemble the top action from the frame.

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625


Original Message:
Sent: 02-25-2024 17:08
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Sorry about the confusion my initial question caused. Here is a clarification.

Here is my current protocol for bedding:

1) I bed the action in the piano using the knock method with the side bocks tightened down. I make sure the action is bedded properly with sustain pedal up, then down, then with shift pedal activated while pressing up and down with the sustain pedal. So, I bed the action frame in four different positions. 1-Sustain disengaged, 2-Sustain pedal engaged, 3-Shift pedal engaged with sustain pedal disengaged, 4-Shift pedal engaged with sustain pedal disengaged.

2) I then set key dip on sample keys up and down the keyboard while it is still in the piano.

3) I take the action out of the piano and put it on the Edwards dolly. I do not touch the glide bolts, but use the Edwars dolly adjustments to match the exact key dip that was set in the piano for each of the sample notes I am regulating. Sometimes I will take the top action off in order to install a capstan boat to figure out how much it needs to be moved if that is a problem. Then I reinstall the top action.

4) I then put the action back into the piano, install and screw down the side blocks and let it sit for a while. The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem.

All your comments have been helpful to think about this issue, and makes me think of the questions below: 

?- I do wonder if using the WNG bedding gauge instead of the knock bedding method would be a more accurate way of bedding the action.

?- I also wonder if on some pianos taking the action in and out of the piano can actually minutely shift the position of the wood joints that hold the action frame together. If this is the case then the bedding will always change when the action is removed and put back into the piano. The piano I am working on is from 1922, so I would not be surprised if the wooden key frame joints have deteriorated. A remedy for this would be to take apart the action frame on older pianos and reglue all the joints. This is something that I have never thought of before, but it might actually be something that would help with action frame stability on old pianos. Do some piano rebuilders do this? Take apart old action frames and reglue them before doing their action work? 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com

Hi Paul, Yes, all stack screws are tight. If any become loose I put West Systems epoxy in the hole and re-thread it to create a very tight screw fit. And yes, the stack feet are all sitting squarely on the frame. I am meticulous about these things. In addition, I always let the stack sit in the piano for hours or overnight after putting it back into the piano in order to let the action frame settle and adjust to the key bed. 

What I am wondering is, are other techs having this same experience as I am having, or is it not an issue? Or do you all notice changes in the dip when you re-bed the action, but don't worry about it?

Are all the stack screws absolutely tight?  Does the stack sit squarely on the feet of the keyframe?  Is the hammer rail straight when it's screwed down?   I suggest that the stack is influencing the flexing of the keyframe so that when you put it in and take it it's changing the bedding.

Peter, Slight knocking, usually on the first and second bolt from the left, bass side of the piano.

Joe

Joe,

Knocking everywhere? Or just one or two studs knocking ever so slightly? 

Peter Grey Piano Doctor 

Yes, David, when I say the bedding is off after putting the action back into the piano after having it on the Edwards Trolley, I mean that it is knocking. Then  after I re-bed the action the Dip has changed. I would have to keep better track of how much the Dip changes, but it is obvious when I feel it on the Dip Block. I would estimate the change to be around a .006 to .012, but I am not exactly sure. I will pay better attention to it and write down when this happens. 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-26-2024 09:20
From: Peter Grey
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

In addition to David's question(s) just how much has the dip spec changed in this scenario? 

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com


Original Message:
Sent: 02-26-2024 00:55
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Hi Joe -

Thanks for playing along.  I have a few more thoughts on your enumerated points:

This comment strikes me as key -

"The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem."

What do you mean, precisely, that "the bedding is off"?  Is it knocking?  Then, once you correct it, is the dip still incorrect?  By how much?  Does this happen all the time or only sometimes? It's possible to imagine that, with a 'lightly' bedded frame, changes in humidity can produce such symptoms.  Also, we didn't establish whether this happens with particular manufacturers or across brands.  

 A potential variable in the 'knock' method, even without the problem of a possible absence of keyframe crown that I previously mentioned, is the actual amount of pressure you chose to have being exerted by the glides.  We gauge this by assessing how much force we have to employ in lifting the action to induce the knock. 

You thought about the possibility of the keyframe members having become unglued, which is worth checking at the outset, but most frames (I think) are secured with screws.  On the other hand, there's always potential for some effect when you disassemble and reassemble the top action from the frame.

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625


Original Message:
Sent: 02-25-2024 17:08
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Sorry about the confusion my initial question caused. Here is a clarification.

Here is my current protocol for bedding:

1) I bed the action in the piano using the knock method with the side bocks tightened down. I make sure the action is bedded properly with sustain pedal up, then down, then with shift pedal activated while pressing up and down with the sustain pedal. So, I bed the action frame in four different positions. 1-Sustain disengaged, 2-Sustain pedal engaged, 3-Shift pedal engaged with sustain pedal disengaged, 4-Shift pedal engaged with sustain pedal disengaged.

2) I then set key dip on sample keys up and down the keyboard while it is still in the piano.

3) I take the action out of the piano and put it on the Edwards dolly. I do not touch the glide bolts, but use the Edwars dolly adjustments to match the exact key dip that was set in the piano for each of the sample notes I am regulating. Sometimes I will take the top action off in order to install a capstan boat to figure out how much it needs to be moved if that is a problem. Then I reinstall the top action.

4) I then put the action back into the piano, install and screw down the side blocks and let it sit for a while. The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem.

All your comments have been helpful to think about this issue, and makes me think of the questions below: 

?- I do wonder if using the WNG bedding gauge instead of the knock bedding method would be a more accurate way of bedding the action.

?- I also wonder if on some pianos taking the action in and out of the piano can actually minutely shift the position of the wood joints that hold the action frame together. If this is the case then the bedding will always change when the action is removed and put back into the piano. The piano I am working on is from 1922, so I would not be surprised if the wooden key frame joints have deteriorated. A remedy for this would be to take apart the action frame on older pianos and reglue all the joints. This is something that I have never thought of before, but it might actually be something that would help with action frame stability on old pianos. Do some piano rebuilders do this? Take apart old action frames and reglue them before doing their action work? 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-25-2024 13:43
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Joe -

  I sensed some basic confusion in your original  question and wondered how you might re-frame (NPI) it, after the numerous comments you received, but, while waiting, I had a few followup questions for you-

• why would you be setting keydip out of the piano, on a caddy that can't possibly have the same controlled adjustability as something like Chris Brown's set up accomplishes?  (note: there HAD to be a reason he devoted so many brain cells to the project)
• you say the key dip changes every time you re-bed the keyframe.  Others have already questioned this.  Of course key dip will change if you alter the bedding, but the question is: why are you 're' bedding, if your painstaking effort was successful to begin with.  I think your focus needs to remain with the reliablity of the bedding process and the applicability of that process to the given manufacturer.  As Horace Greeley further described, even within Steinway, the methods of construction have changed over time, requiring modifications in approach.
• from my own experience (specific to Steinway), I'll share these marginally useful observations:
  
  • check shape of keybed with straight edge for any obvious anomalies
  • check underside of keyframe, front to back, along its entire length for the presence (or absence) of 'crown', which is part of Steinway design.  If the frame has collapsed (straight edge contacts balance rail wood) it will be impossible to reliably bed using the traditional 'tap' method, and will potentially create other problems such as excess shift friction
  • BACK  RAIL!!! I admit it. I dislike them.  I tend to avoid them, ususally to my detriment.  While this may be one of those steps that Bill Ballard referenced as not having a significant impact on keydip, the problems associated with poorly fit back rail can be subtle and persistent, especially if there is inadequate postive pressure from 'dogs' (or dags?).
  • To add to the confusion, I would re-pose a question to Horace (or anyone else who knows) that I think I asked some years ago: I thought I remember an 'old-timer' describing the intentional flexing of the frame with extra pressure from the glide adjustment to increase the stiffness of the frame, to reflect energy.  This would require that the dogs/dags exert positive contact to prevent the back rail from lifting, and not be excessive enough to create shift drag or squeaks.  Anyone know if I made this up?

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625

Hi Paul, Yes, all stack screws are tight. If any become loose I put West Systems epoxy in the hole and re-thread it to create a very tight screw fit. And yes, the stack feet are all sitting squarely on the frame. I am meticulous about these things. In addition, I always let the stack sit in the piano for hours or overnight after putting it back into the piano in order to let the action frame settle and adjust to the key bed. 

What I am wondering is, are other techs having this same experience as I am having, or is it not an issue? Or do you all notice changes in the dip when you re-bed the action, but don't worry about it?

Are all the stack screws absolutely tight?  Does the stack sit squarely on the feet of the keyframe?  Is the hammer rail straight when it's screwed down?   I suggest that the stack is influencing the flexing of the keyframe so that when you put it in and take it it's changing the bedding.

Peter, Slight knocking, usually on the first and second bolt from the left, bass side of the piano.

Joe

Joe,

Knocking everywhere? Or just one or two studs knocking ever so slightly? 

Peter Grey Piano Doctor 

Yes, David, when I say the bedding is off after putting the action back into the piano after having it on the Edwards Trolley, I mean that it is knocking. Then  after I re-bed the action the Dip has changed. I would have to keep better track of how much the Dip changes, but it is obvious when I feel it on the Dip Block. I would estimate the change to be around a .006 to .012, but I am not exactly sure. I will pay better attention to it and write down when this happens. 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-26-2024 09:20
From: Peter Grey
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

In addition to David's question(s) just how much has the dip spec changed in this scenario? 

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com


Original Message:
Sent: 02-26-2024 00:55
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Hi Joe -

Thanks for playing along.  I have a few more thoughts on your enumerated points:

This comment strikes me as key -

"The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem."

What do you mean, precisely, that "the bedding is off"?  Is it knocking?  Then, once you correct it, is the dip still incorrect?  By how much?  Does this happen all the time or only sometimes? It's possible to imagine that, with a 'lightly' bedded frame, changes in humidity can produce such symptoms.  Also, we didn't establish whether this happens with particular manufacturers or across brands.  

 A potential variable in the 'knock' method, even without the problem of a possible absence of keyframe crown that I previously mentioned, is the actual amount of pressure you chose to have being exerted by the glides.  We gauge this by assessing how much force we have to employ in lifting the action to induce the knock. 

You thought about the possibility of the keyframe members having become unglued, which is worth checking at the outset, but most frames (I think) are secured with screws.  On the other hand, there's always potential for some effect when you disassemble and reassemble the top action from the frame.

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625


Original Message:
Sent: 02-25-2024 17:08
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Sorry about the confusion my initial question caused. Here is a clarification.

Here is my current protocol for bedding:

1) I bed the action in the piano using the knock method with the side bocks tightened down. I make sure the action is bedded properly with sustain pedal up, then down, then with shift pedal activated while pressing up and down with the sustain pedal. So, I bed the action frame in four different positions. 1-Sustain disengaged, 2-Sustain pedal engaged, 3-Shift pedal engaged with sustain pedal disengaged, 4-Shift pedal engaged with sustain pedal disengaged.

2) I then set key dip on sample keys up and down the keyboard while it is still in the piano.

3) I take the action out of the piano and put it on the Edwards dolly. I do not touch the glide bolts, but use the Edwars dolly adjustments to match the exact key dip that was set in the piano for each of the sample notes I am regulating. Sometimes I will take the top action off in order to install a capstan boat to figure out how much it needs to be moved if that is a problem. Then I reinstall the top action.

4) I then put the action back into the piano, install and screw down the side blocks and let it sit for a while. The problem is when I come back to the piano either later in the day or the next day, the bedding is off and needs to be reset. So, I reset the bedding to where it is good again and then check the dip and the dip has changed. This is the problem.

All your comments have been helpful to think about this issue, and makes me think of the questions below: 

?- I do wonder if using the WNG bedding gauge instead of the knock bedding method would be a more accurate way of bedding the action.

?- I also wonder if on some pianos taking the action in and out of the piano can actually minutely shift the position of the wood joints that hold the action frame together. If this is the case then the bedding will always change when the action is removed and put back into the piano. The piano I am working on is from 1922, so I would not be surprised if the wooden key frame joints have deteriorated. A remedy for this would be to take apart the action frame on older pianos and reglue all the joints. This is something that I have never thought of before, but it might actually be something that would help with action frame stability on old pianos. Do some piano rebuilders do this? Take apart old action frames and reglue them before doing their action work? 

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-25-2024 13:43
From: David Skolnik
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Joe -

  I sensed some basic confusion in your original  question and wondered how you might re-frame (NPI) it, after the numerous comments you received, but, while waiting, I had a few followup questions for you-

• why would you be setting keydip out of the piano, on a caddy that can't possibly have the same controlled adjustability as something like Chris Brown's set up accomplishes?  (note: there HAD to be a reason he devoted so many brain cells to the project)
• you say the key dip changes every time you re-bed the keyframe.  Others have already questioned this.  Of course key dip will change if you alter the bedding, but the question is: why are you 're' bedding, if your painstaking effort was successful to begin with.  I think your focus needs to remain with the reliablity of the bedding process and the applicability of that process to the given manufacturer.  As Horace Greeley further described, even within Steinway, the methods of construction have changed over time, requiring modifications in approach.
• from my own experience (specific to Steinway), I'll share these marginally useful observations:
  
  • check shape of keybed with straight edge for any obvious anomalies
  • check underside of keyframe, front to back, along its entire length for the presence (or absence) of 'crown', which is part of Steinway design.  If the frame has collapsed (straight edge contacts balance rail wood) it will be impossible to reliably bed using the traditional 'tap' method, and will potentially create other problems such as excess shift friction
  • BACK  RAIL!!! I admit it. I dislike them.  I tend to avoid them, ususally to my detriment.  While this may be one of those steps that Bill Ballard referenced as not having a significant impact on keydip, the problems associated with poorly fit back rail can be subtle and persistent, especially if there is inadequate postive pressure from 'dogs' (or dags?).
  • To add to the confusion, I would re-pose a question to Horace (or anyone else who knows) that I think I asked some years ago: I thought I remember an 'old-timer' describing the intentional flexing of the frame with extra pressure from the glide adjustment to increase the stiffness of the frame, to reflect energy.  This would require that the dogs/dags exert positive contact to prevent the back rail from lifting, and not be excessive enough to create shift drag or squeaks.  Anyone know if I made this up?

------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625

Wheels do not sit directly centered under the legs.  Incorrect position of the wheels can cause the keybed to be torqued.

People may scoff at this protocol, but I find it critical as a starting point:  the wheels need to be set so they are facing either to the front or the back.  This will alter the regulation.  If they are set facing either side of the piano the keybed will be torqued which in turn will change the regulation.  If the keybed is torqued, installing the action will further affect the torqued situation.

Tim is right on the money.

I was told years ago though that Bosendorfer recommends that the front casters be oriented pointing inwards, so that if there is going to be any flex in the bed, it would be to flex the middle upwards (theoretically always the same if oriented thusly). Other orientation would tend to be random (again assuming a flexible keybed).

I try to follow the above rule. Some simple testing should prove whether you have an issue there or not.

Peter Grey Piano Doctor 

Wheels do not sit directly centered under the legs.  Incorrect position of the wheels can cause the keybed to be torqued.

People may scoff at this protocol, but I find it critical as a starting point:  the wheels need to be set so they are facing either to the front or the back.  This will alter the regulation.  If they are set facing either side of the piano the keybed will be torqued which in turn will change the regulation.  If the keybed is torqued, installing the action will further affect the torqued situation.

Wow. Thanks to all for their erudition. 

Sure would be easier if everyone played the harmonica.

Tim is right on the money.

I was told years ago though that Bosendorfer recommends that the front casters be oriented pointing inwards, so that if there is going to be any flex in the bed, it would be to flex the middle upwards (theoretically always the same if oriented thusly). Other orientation would tend to be random (again assuming a flexible keybed).

I try to follow the above rule. Some simple testing should prove whether you have an issue there or not.

Peter Grey Piano Doctor 

Wheels do not sit directly centered under the legs.  Incorrect position of the wheels can cause the keybed to be torqued.

People may scoff at this protocol, but I find it critical as a starting point:  the wheels need to be set so they are facing either to the front or the back.  This will alter the regulation.  If they are set facing either side of the piano the keybed will be torqued which in turn will change the regulation.  If the keybed is torqued, installing the action will further affect the torqued situation.

Wow, I did not know that about setting the direction of the casters on each leg. Interesting!

And thanks Chris Brown for taking the time to go into such detail. A lot to analyze there. I will reread what you wrote a number of times.

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com
------------------------------


Original Message:
Sent: 02-29-2024 13:56
From: Steven Rosenthal
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Wow. Thanks to all for their erudition. 

Sure would be easier if everyone played the harmonica.

------------------------------
Steven Rosenthal RPT
Honolulu HI
(808) 521-7129


Original Message:
Sent: 02-29-2024 11:13
From: Peter Grey
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Tim is right on the money.

I was told years ago though that Bosendorfer recommends that the front casters be oriented pointing inwards, so that if there is going to be any flex in the bed, it would be to flex the middle upwards (theoretically always the same if oriented thusly). Other orientation would tend to be random (again assuming a flexible keybed).

I try to follow the above rule. Some simple testing should prove whether you have an issue there or not.

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com


Original Message:
Sent: 02-29-2024 08:30
From: Tim Coates
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Wheels do not sit directly centered under the legs.  Incorrect position of the wheels can cause the keybed to be torqued.

People may scoff at this protocol, but I find it critical as a starting point:  the wheels need to be set so they are facing either to the front or the back.  This will alter the regulation.  If they are set facing either side of the piano the keybed will be torqued which in turn will change the regulation.  If the keybed is torqued, installing the action will further affect the torqued situation.

------------------------------
Tim Coates RPT
Sioux Falls SD

Joe went: "Wow, I did not know that about setting the direction of the casters on each leg. Interesting!"

It's always interesting to put a number on it, with straight-edges or dial indicators. (This one is easy to remedy: keep the bass and treble casters in the direction of moving forward.) You could take a piano which has rolled around all day on stage and then  stop it at somewhere on the stage and measure its flatness with a straight edge. Then rotate these casters 90º away from or back towards each other, and measure again.

I was curious about how much the sustain pedal pulls downwards on the middle of the keybed. A dial indicator read 7mils (.007"): the thickness of ordinary white paper. So I figure I'll put in 12 mils (from nothing) at the glides, which I don't think is a serious deflection/imposition. Sure, it's a fluid situation, but at least it's something I can be consistent with.

------------------------------
William Ballard RPT
WBPS
Saxtons River VT
802-869-9107

"Our lives contain a thousand springs
and dies if one be gone
Strange that a harp of a thousand strings
should keep in tune so long."
...........Dr. Watts, "The Continental Harmony,1774
------------------------------


Original Message:
Sent: 03-05-2024 12:27
From: Joseph Burros
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Wow, I did not know that about setting the direction of the casters on each leg. Interesting!

And thanks Chris Brown for taking the time to go into such detail. A lot to analyze there. I will reread what you wrote a number of times.

------------------------------
Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com


Original Message:
Sent: 02-29-2024 13:56
From: Steven Rosenthal
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Wow. Thanks to all for their erudition. 

Sure would be easier if everyone played the harmonica.

------------------------------
Steven Rosenthal RPT
Honolulu HI
(808) 521-7129


Original Message:
Sent: 02-29-2024 11:13
From: Peter Grey
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Tim is right on the money.

I was told years ago though that Bosendorfer recommends that the front casters be oriented pointing inwards, so that if there is going to be any flex in the bed, it would be to flex the middle upwards (theoretically always the same if oriented thusly). Other orientation would tend to be random (again assuming a flexible keybed).

I try to follow the above rule. Some simple testing should prove whether you have an issue there or not.

Peter Grey Piano Doctor 

------------------------------
Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com


Original Message:
Sent: 02-29-2024 08:30
From: Tim Coates
Subject: Does anyone have a protocol for bedding the action so that key dip remains accurate?

Wheels do not sit directly centered under the legs.  Incorrect position of the wheels can cause the keybed to be torqued.

People may scoff at this protocol, but I find it critical as a starting point:  the wheels need to be set so they are facing either to the front or the back.  This will alter the regulation.  If they are set facing either side of the piano the keybed will be torqued which in turn will change the regulation.  If the keybed is torqued, installing the action will further affect the torqued situation.

------------------------------
Tim Coates RPT
Sioux Falls SD