Doug,
If the action was playing OK, before removing the cloth, I would look first at the case parts, such as the fall board, key slip, as well where on the balance pin the key button is, and how far into the front mortise the key descends or rests.
The the back rail cloth partially determines the height of the capstan (in conjunction with the balance punchings,) which relates to the action elevation height, and hammer boring, as all those relate to the overall string height. I’m sure some out there have a much more eloquent and detailed description.
Joe Wiencek
NYC
Original Message:
Sent: 1/3/2024 7:05:00 AM
From: Douglas Mahard
Subject: Backrail cloth
Happy new year all,
I recently received an 85 note S&S B for action refurbishing and regulation. After pulling the backrail cloth up for replacement, underneath was three layers of different cloth thickness' and some old paper card stock. The five materials came in at a combined thickness of .3405 inches. See attached photo. This is not the first time this action had been refurbished.
The presence of all the material under the thick green backrail cloth made me curious as to how one determines the thickness needed for any specific grand action. I normally try and get as close to what the original thickness was, given all the other parameters associated with key front height and damper lever height seem to be reasonable.
This discovery of five layers of backrail material got me thinking. How is the thickness of backrail under key material determined?
Doug Mahard
------------------------------
Doug Mahard
CT Chapter
203-266-6688
------------------------------