Pianotech

Greetings,

Going through the action on a 1933 Mason & Hamlin model "A". The original backrail cloth had both edges (front and back) glued down to the backrail of the keyframe. While I do not always replace backrail cloth when regulating, this is the first one I have noticed that did not have just a single edge glued down.

The question is: what are the pros and cons of gluing both edges? Any recommendations as to whether or not it is advisable to do the same with the new b/r cloth?

Thanks,

Alan

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Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
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Alan, verticals have always seemed to be simply glued down in the middle of the felt, I think some grands too. The main 'pro' to gluing one edge is that you can shim the felt from underneath to fine tune or perhaps at some later date after wear; I don't know what the downside would be.

Perhaps the felt on the M&H isn't original?

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Steven Rosenthal RPT
Honolulu HI
(808) 521-7129
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Cannot say for sure, Steven (as this 92 year old action does not appear to have had anything done to it except for key re-covering and capstan [and frontrail keypin!] turning), but it sure looks to be original to me.

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Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
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Original Message:
Sent: 04-30-2025 22:01
From: Steven Rosenthal
Subject: Backrail cloth: glue both edges?

Alan, verticals have always seemed to be simply glued down in the middle of the felt, I think some grands too. The main 'pro' to gluing one edge is that you can shim the felt from underneath to fine tune or perhaps at some later date after wear; I don't know what the downside would be.

Perhaps the felt on the M&H isn't original?

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

Alan,

"I was always told" Steinway (and others') backrail cloth was glued down fore and aft to place the upper surface area under tension. This is done in conjunction with a narrow strip of nameboard felt underneath at the center to hump the backrail cloth upward. The thinking is if this backrail cloth surface is taut it is more resilient, and supports a better condition of uniform key level over the life on the instrument.

David G. Hughes, RPT

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David Hughes RPT
Vintage Case Parts
Glyndon MD
(443) 522-2201
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Hi David,

Great to reap the benefit of your extensive rebuilding experience in this matter!

Sounds like you have followed the advice you have received from manufacturers re: gluing of the cloth. Makes sense to me, as well.

Alan

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Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
------------------------------

Original Message:
Sent: 05-01-2025 09:30
From: David Hughes
Subject: Backrail cloth: glue both edges?

Alan,

"I was always told" Steinway (and others') backrail cloth was glued down fore and aft to place the upper surface area under tension. This is done in conjunction with a narrow strip of nameboard felt underneath at the center to hump the backrail cloth upward. The thinking is if this backrail cloth surface is taut it is more resilient, and supports a better condition of uniform key level over the life on the instrument.

David G. Hughes, RPT

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David Hughes RPT
Vintage Case Parts
Glyndon MD
(443) 522-2201
------------------------------

One further consideration for performance pianos on the matter of, "to glue, or not to glue," the aft edge of the back rail cloth comes to mind.

At the last convention, I was fortunate to attend a class by Bechstein's traveling and teaching concert technician, Torban Galen. One of the many valuable takeaways he shared was that if an artist wants the action to be lighter, and the technician only has a few minutes to affect this change, if the aft edge of the back rail cloth is not glued down, paper shims may be inserted under the cloth.

Like the "Montal pedal", this both decreases the hammer blow distance and the key dip, which has the effect of making the action seem lighter while maintaining the amount of after-touch. And as a bonus, it reverses even more quickly than it installs! 

Of course, this only works if the aft edge of the back rail cloth is not glued down. Don't think I would cut an already aft-glued back rail cloth in order to make this modification.

Alan

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Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
------------------------------

Original Message:
Sent: 05-01-2025 09:45
From: Alan Eder
Subject: Backrail cloth: glue both edges?

Hi David,

Great to reap the benefit of your extensive rebuilding experience in this matter!

Sounds like you have followed the advice you have received from manufacturers re: gluing of the cloth. Makes sense to me, as well.

Alan

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Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
------------------------------


Original Message:
Sent: 05-01-2025 09:30
From: David Hughes
Subject: Backrail cloth: glue both edges?

Alan,

"I was always told" Steinway (and others') backrail cloth was glued down fore and aft to place the upper surface area under tension. This is done in conjunction with a narrow strip of nameboard felt underneath at the center to hump the backrail cloth upward. The thinking is if this backrail cloth surface is taut it is more resilient, and supports a better condition of uniform key level over the life on the instrument.

David G. Hughes, RPT

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David Hughes RPT
Vintage Case Parts
Glyndon MD
(443) 522-2201