Based on my still limited understanding of the fine physics of the action, we'd want the more efficient connection between the flange and the rail to limit any, even if only very slight, movement or loss of energy at that point.
On the most extreme end, with a soft felt/cloth under the flange we
could get twisting (axial rotation of the shank), rocking (fore and aft) or simply variation in impact based on force-harder hammer blow would lead to more movement of the flange on a soft support.
On the other hand, nothing under the flange
could make aligning and maintaining hammer alignment a little more challenging as there would be little friction between wood/wood or wood and metal-we'd have to over tighten the flange screws, exacerbating wear from seasonal humidity changes.
Maybe the difference is negligible in practice?
I appreciate the recommendation for sandpaper and have some nice Norton wet/dry 220 that is black. Thinking it should work nicely. I'll post some photos for other to reference once I get into it.
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Daniel Petrzelka
Mount Vernon WA
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Original Message:
Sent: 10-28-2018 01:20
From: Edward McMorrow
Subject: Main Action rail - sand paper
I have heard this claim about cloth under hammer flanges "damping" noise and it simple does not pass the smell and double blind test. There is a screw whose head must firmly contact the flange and this can transmit all the vibration available right into the action frame and keyframe right past the cloth.
Do a test sometime. Remove the cloth from a few notes, (and be sure to line the hammer up the same as it was), and play the notes. I can't hear any difference! Maybe some can, I don't know but I can only go by what my own ears tell me.
I despise the self-adhesive pressed felt hammer rail strips Steinway uses. They compress over time so every time one travels and or spaces the flange the cloth has to settle and this changes the travel and spacing again. I want it STABLE!
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Edward McMorrow
Edmonds WA
425-299-3431
Original Message:
Sent: 10-27-2018 19:12
From: Karl Roeder
Subject: Main Action rail - sand paper
Mr. Grey.
I was told by the engineering department that the purpose of the cloth on the hammershank rail is to dampen noise. Specifically the noise caused by the vibrations transmitted from the hammer striking the string back to the hammershank flange. Any gaps between the flange and the rail could cause unwanted sound when the vibrations caused the flange to flex. Given the Steinway flange mounting system, there will usually be a lot of such gaps caused by the use of traveling paper. The repetition experiences no such violent collision due to the escapement mechanisms. Thus no cloth on the repetition rail.
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Karl Roeder
Pompano Beach FL
Original Message:
Sent: 10-27-2018 18:48
From: Peter Grey
Subject: Main Action rail - sand paper
Any speculation on why Steinway used/uses cloth/felt on the hammer rail anyway? Why not on the whippen rail? Why not just straight to the rail?
Pwg
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Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com
Original Message:
Sent: 10-25-2018 20:11
From: Jon Page
Subject: Main Action rail - sand paper
For wooden action rails, I use a heavy "J" weight paper which has pressure sensitive adhesive from 6" rolls. Two strips cut to width needed for the length of the rail.
For S&S, I use fine emory cloth in 1" rolls and rip[ in half lengthwise to fit the rail's width. For the tenor section, I bend the center brass support to get the double-sided tape and cloth laid down in one piece.
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Regards,
Jon Page
Original Message:
Sent: 10-25-2018 15:16
From: Alan Eder
Subject: Main Action rail - sand paper
I was first taught about substituting sand paper for cloth on Steinways by someone who used 80 grit. I have done that, but have more recently used 120 to 220. After learning of Jon and Ed's practices, though, I think I will try a finer grit next time.
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: 10-25-2018 14:25
From: Daniel Petrzelka
Subject: Main Action rail - sand paper
Yes, this Baldwin G with metal rail does have machine screws for the flanges-10-24 thread I believe, with a tapered point for alignment. I would be concerned about abrasive entering the treads if I were to punch with an awl and then tread the machine screws.
Two parallel strips seems like a safer bet for this one.
I have cloth backed emory rolls, 1" wide, but it seems pretty thick for this application. Any concern about the effect on the geometry? I'm inclined to use the thinner 220 sheet abrasive cut into to strips.
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Daniel Petrzelka
Mount Vernon WA
Original Message:
Sent: 10-25-2018 13:37
From: Jon Page
Subject: Main Action rail - sand paper
Leaving a gap at the screw line is OK. Some Baldwins have machine screws and punching with an awl will not work. For S&S rails, I use fine emory cloth (bought in rolls from Klingspor) and double sided tape (3M for window treatment) and punch the holes with an awl.
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Regards,
Jon Page
Original Message:
Sent: 10-25-2018 00:55
From: Willem Blees
Subject: Main Action rail - sand paper
Two thin strips is a good idea. But you also glue on a solid strip and use an awl to punch holes where the screws will be. It's not that difficult. Done it many times.
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Willem "Wim" Blees, RPT
Mililani, HI 96789
Original Message:
Sent: 10-25-2018 00:26
From: Daniel Petrzelka
Subject: Main Action rail - sand paper
Thanks all.
Two strips sounds very straightforward - I had been scheming on measuring punching the holes out prior to gluing, but that will save considerable time.
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Daniel Petrzelka
Mount Vernon WA
Original Message:
Sent: 10-24-2018 22:08
From: Edward McMorrow
Subject: Main Action rail - sand paper
I do much as Jon does on the flat rails. Two strips on either side of the screw holes. I do use 3M 77 spray glue on the metal Baldwins. I prefer the grip of 220 grit.
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Edward McMorrow
Edmonds WA
425-299-3431
Original Message:
Sent: 10-24-2018 20:58
From: Jon Page
Subject: Main Action rail - sand paper
I buy a roll of 320 grit, pressure sensitive adhesive from Klingspor. 6" rolls with strips cut to the length of the rail. There is no need to punch holes because you install two strips, one on either side of the screw line. Heavy J weight paper.
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Regards,
Jon Page
Original Message:
Sent: 10-24-2018 14:30
From: Willem Blees
Subject: Main Action rail - sand paper
Rubber cement works very well as an adhesive. Use 220 grit wet/dry sand paper.
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Willem "Wim" Blees, RPT
Mililani, HI 96789
Original Message:
Sent: 10-24-2018 13:45
From: Daniel Petrzelka
Subject: Main Action rail - sand paper
This 1920's Baldwin G has the horrible old black plastic/rubber on the main action rail (under the flanges). It is, of course, causing issues as I remove and re-pin flanges while testing flange friction.
I've decided I need to pull all the flange screws, scrape the old material off, and re-align and re-travel them all.
This Baldwin has a metal rail. Is sandpaper the best current material to use a top the main action rail?
Super 77 adhesive?
Any recommendations on what grit paper?
Also favorite material for traveling hammers?
Any thoughts greatly appreciated.
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Daniel Petrzelka
Mount Vernon WA
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