Boy it doesn't take much in this Forum to get a very interesting conversation going. It's nice to know that the half-punching works in both directions. Thanks, everyone!
This is just a temporary mock-up. The binder clip on the hammer affects all three forces (friction, gravitational, and inertial) and is immediately reversible. The half-punching (in this case, to increase Strike Balance Ratio) works on the latter two, but to do this with the existing BR punchings is not reversible, leaving you with a new, different SBR, which is either lighter or heavier than the original. If you carefully remove the existing BR punchings and swap in a set of half-punchings, the swap-in set had better be the same thickness as the originals, the aftertouch change, complicating the pianist's impressions. The best of all worlds is that someone has already set the keyboard with half-punchings, and all you have to do is rotate them. Even here, though there's the chance that the key level will get upset and you'll have to spend some time, adding or pulling paper punchings to restore the level.
So, I'm going with the binder clips. Now the how-to-question: will the clips damage WNG shanks? Any DAMHIKs out there?
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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
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Original Message:
Sent: 11-03-2021 10:58
From: David Love
Subject: Half Felt BR Punching to Increase Action Resistence
The key at rest actually sits on the backside of the BR punching and as it is depressed it rotates onto the front side of the punching. The key ratio, therefore, is actually changing through the key stroke. So cutting the backside of the punching will slightly move the pivot point forward and raise the key ratio and the AR somewhat. Cutting the punching on the front side only affects the KR after the key contact point pivots forward during the last half of the key stroke which is why it's not as effective as the shim method.
We will feel the most change if what we do affects the AR at the beginning of the stroke rather than at the end because inertia is more of a factor when we are initiating movement. Therefore cutting the backside of the punching to raise the AR is more effective than cutting the front of the punching to lower the AR.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
Original Message:
Sent: 11-03-2021 05:01
From: Philip Stewart
Subject: Half Felt BR Punching to Increase Action Resistence
No, trimming the back side will have 0 effect on the resistance. The key is pressed down at the front, meaning it will pivot at the front side of the punching. Changing the back side will not affect the pivot point in any way. It may, however, make the key level regulation unstable and inconsistent.
Original Message:
Sent: 11/2/2021 10:55:00 AM
From: Bill Ballard
Subject: Half Felt BR Punching to Increase Action Resistence
I've never had occasion to use the BR punching to as a quick way to lower action resistance (presumably BW, because it acts on the leverage). So I don't know the precision (across the keyboard) in which it lowers BW: the variance in its effect. Also, not having the experience here, I wouldn't know if the closeness to the BR pin's hole will vary the degree to which trimming it will vary its effect ( ie., from 0 untrimmed to its full amount, actually trimming into the hole.
All of this would be useful to know because I have an action in which the resistance (either friction or BW) needs to be raised. Because we won't know by how much until the pianist tries it, it has to be both variable and undoable. Also, temporary alterations in BW (binder clips on the shanks) or FW (back-leading on the keys) also increase the inertial resistance, and I'd like to avoid putting extra variables into the experiment. Turning the front key pins (to increase friction) is variable and undoable. However, I'd rule it out as a permanent fix.
So, trimming the BR punchings seems to be the trick IF trimming on the backside is as reliable an adjustment as trimming the front side. I also would do any trimming on felt punchings of my own, swapped in to avoid make permanent changes on the existing ones.
Additional info: the action is a new WNG, so a thorough repinning of the shanks would be a little trickier than if they were wood (the best idea here is pin pricks at 3/9o'clock around the birdseyes).
Ideas? 10Q.
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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
+++++++++++++++++++++
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