Another advantage of the binder clips is that one can adjust to even out down weight.
Original Message:
Sent: 04-14-2024 03:00
From: Geoff Sykes
Subject: Touchweight question
Yes, the goal was to make the action heavier. The half cardboard punching was placed on the player side of the balance pin. I separated it from the top felt punching with one thin paper punching to avoid having the half punching work its way out due to any possible rocking motion from the felt punching. For the most part this has worked, but it's not foolproof. A teeny tiny drop of glue, perhaps gluing the half punching to a paper punching, would probably work very well. Next time, however, I'm trying the mini binder clips first.
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Geoff Sykes, RPT
Los Angeles CA
Original Message:
Sent: 04-14-2024 02:06
From: David Love
Subject: Touchweight question
Floyd
Floyd wrote: "The stated objective is to make the action lighter, not heavier, and the half punching used as a shim is mounted on the player side of the balance rail, not the stack side."
The original post was actually to make the action heavier, not lighter. In that case you want to move the fulcrum toward the player (as you stated). Or, in the case of the shim, place it in front of the balance rail . To make the action lighter you would want to mount the cut punching behind the balance rail or the shim underneath the back side of the BR punching. Essentially, the goal is to move the fulcrum either forward (to increase the AR) or back (to lower the AR). My statement was more for general purposes but I'm typically trying to make actions lighter rather than heavier so fell into that trend.
Whether you use a cloth punching or a cardboard punching probably doesn't matter though most of what I've seen is the cloth punching being glued. The shim raises either the front or the back of the existing punching and thus moves the fulcrum which effectively changes the AR. via the KR.
For reasons already stated, I prefer the shim method but in this case would opt for the mini binder clips as the best, and easiest, option which is easily changed without ever removing the stack.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
Original Message:
Sent: 04-13-2024 21:16
From: Floyd Gadd
Subject: Touchweight question
I think a couple of things are being missed from the original post. The stated objective is to make the action lighter, not heavier, and the half punching used as a shim is mounted on the player side of the balance rail, not the stack side. Second, a cardboard half-punching is being used, not a cloth one, so, I presume, it is placed under the cloth punching. This being the case, nothing even semi-permanent needs to be done here in terms of gluing. I suppose the half-punching could be glued to the balance rail, but it could also simply be glued to one of the other punchings that sits under it. The solution Geoff has chosen is almost identical to the veneer shim approach, though I usually imagine a veneer shim to be less wide in the horizontal dimension than what is being provided by the cardboard punching, again, assuming the veneer shim is place right up against the balance pin.
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Floyd Gadd RPT
Regina SK
(306) 502-9103
Original Message:
Sent: 04-13-2024 03:19
From: David Love
Subject: Touchweight question
The stuff I buy in packages of small sheets is about .040" or 1mm. I prefer to use it with thin felt punchings. Most lumber years carry a selection of hardwood veneers.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
Original Message:
Sent: 04-12-2024 15:25
From: Joe Wiencek
Subject: Touchweight question
David,
Do you have an approximate thickness of the veneer you use for lowering the action ratio?
Thanks,
Joe Wiencek
Original Message:
Sent: 4/11/2024 6:51:00 PM
From: David Love
Subject: RE: Touchweight question
Sorry, lots of thumbos which I've now corrected, hopefully
Of course it's up to you what to do but cut punchings is not the simplest method. Binder clips are much simpler. All you have to do is clip them on the Shanks and remove the handles, Nothing more to it than that. Thirty minutes. Punchings you have to remove the keys you have to glue the punching on, etc. etc. takes a lot longer. You can also buy cut pinchings (wurzen felt ) that Pianotek used to sell and now Schaff carries them, and you can just exchange the punchings without gluing anything on. They are not cut quite as severely but it's the same idea.
My preference for lowering the key ratio is to put shims behind the balance rail made of thin veneer (I've posted this several times).
Either way you'll have some work to do afterwards. If you put on binder clips, you'll probably have to do some adjusting to the repetition springs. If you do something which changes the action ratio via the key, you'll have to reset the key dip or at least review it. Of course, if you do lower the action ratio by shimming or doing something to change the key ratio you will need more dip, which is why putting veneer shim behind the balance rail is nice as it raises the key marginally. Just cut 1/8" strips and insert them under the existing punching, tack them in place with glue. You can do it on site very easily, takes about 30 minutes plus whatever is necessary for key dip.
For what it's worth I'm not a fan of the cut punching method, not just because of something glued to the bottom the key, but because it only changes the key ratio at the end of the stroke when the cut part of the punching comes into play. Since the key rests on the back of the punching at the outset, the front of the punching doesn't actually come into play until at least halfway through the stroke. By that time the force to overcome inertia has already past. But clearly, there's some disagreement as the best methods.
Good luck.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
Original Message:
Sent: 04-11-2024 11:54
From: Geoff Sykes
Subject: Touchweight question
Oh, I had no plans to go back and change what I've already done. It's working. But gluing in the cut punching's is something I think I will go back and do. Good suggestion. Moving forward, I think I'll try the spring clips next time.
Thanks to all for your replies.
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Geoff Sykes, RPT
Los Angeles CA
Original Message:
Sent: 04-11-2024 11:39
From: Dave Conte
Subject: Touchweight question
David Love is absolutely correct.
However, this would be more work. The fact that the customer is already happy with what you have done has to carry weight in your decision. Shifting methods at this point would start to raise questions and undermine your abilities in their mind. Apart from the punchings shifting out of position, don't mess with it. What you have already done will stay put if you fix the punchings in place with some sort of adhesive unless you deliberately remove it.
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Original Message:
Sent: 4/11/2024 10:52:00 AM
From: David Love
Subject: RE: Touchweight question
I like the mini binder clip solution. You can attach them to the shank at any point on the shank and use them as a slider to adjust both actual downweight and inertia (inertia being primarily a function of SW:AR relationship). I often set up new actions with a mini binder clip attached to the proximal side of the shank and then set the weight at the lightest touchweight I think the customer will like or accept. Then if they want it heavier (or higher inertia--they are not quite the same btw more on that below). I can just slide the clip down the shank (or add another if necessary even). That gives me a quasi-adjustable action and the clips will stay put. I've had them on pianos for years.
There are two aspects to touchweight. There's inertia, the force to overcome acceleration of a mass, and then there's the static downweight, or balance weight if you prefer. The downweight is simply the minimum force required to actuate the key at, for practical purposes, zero acceleration. We don't play the piano in the way that we do a weigh-off because the acceleration is too slow to get the hammer to the string, but it does give us a minimum force required to move the key (which can change with friction). Inertia involves acceleration which is how we play the piano. So you can increase the downweight by, say, removing a lead in the key but that won't appreciably change the inertia. If we remove a lead in order to raise the DW by, let's say, 4 grams, that's about one lead weight approximately 12 grams removed from a distance of about 1/3 of the way from the balance rail to the front of the key. That lead removal will have very little effect on inertia, it just doesn't contribute that much.
So first try and determine if what they want is an increase in the static weight or an increase in inertia (if possible). To increase inertia, you have two basic choices, either increase the SW or increase the AR. It doesn't really matter which one you choose. David S's method below increases the AR, the clip method increases the SW. I find the clip easier, less intrusive on the action (I don't like gluing things to the keys), and, in this case, adjustable.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
Original Message:
Sent: 04-10-2024 22:21
From: Geoff Sykes
Subject: Touchweight question
1991 Yamaha C3. Very nice piano in great condition.
Customer asked me to add weights to the keys because she and her daughter thought it was too light a touch. I talked them out of using weights, and avoided the subject of touch weight analysis and re-leading. As a repair that I could actually do myself, I opted to use the trick I learned years ago, probably here, about adding half a cardboard punching to the player side of the balance rail. Re-leveling the keys was a task but the customer was happy with the result. However, even though I made a point of placing that half punching underneath an existing punching under the thick top felt punching, I've been called back twice now to address several that have slipped out. Looking for recommendations on how I can get these half punching's to remain in place.
Moving forward, next time I'm called to increase touch weight I'll probably invest in those small spring clips and add them to the hammer shanks. Again, a trick I believe I learned here.
Thanks --
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Geoff Sykes, RPT
Los Angeles CA
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