Thanks to all those who participated. I will post an example with data of one of these analyses so you can see the entire process. I'll do it as a PDF attachment so you can print it out if you want and see the step by step process. With some effort you should be able to incorporate this practice into your own weigh off if you want. Oh, and btw (Mr Hughes) you don't have to send me any money.
Original Message:
Sent: 07-16-2023 01:57
From: David Love
Subject: Touchweight consulting beta testing
Thanks David. I look forward to seeing the data but please send it to me privately.
I'm not a fan of hardwood buttons for reasons cited.
As I've mentioned to a couple of people, my output is only as good as your input and friction can contribute to measurement error, or at least discrepancies. So preparing the action for the proper measuring of UW and DW is important. Everything else is static (FW and SW).
The argument that that's why you should measure levers, come up with the AR and then plug in the static weights is that those measurements are also not easy to be consistent with and ARs can vary from end to end, which they often do. The way around that is to calculate final numbers using trendines derived from samples across the keyboard which will capture that AR change. Unfortunately that requires measuring the balance weight, or UW and DW, which brings with it variances brought about by our relatively crude way of talking dynamic measurement that require the interpretation of movement.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
Original Message:
Sent: 07-15-2023 11:26
From: David Skolnik
Subject: Touchweight consulting beta testing
Hi David –
Happy belated Bastille Day.
I've been collecting additional data from this piano, whether or not it ultimately suits your current objective. I'm quite experienced in collecting Stanwoodian data, at this point, though I still find room for interpretation as it relates to the varying effect of friction (depending upon its source) on the movement of the hammer. In the case of the D in question (#51382)!!, I've had to make multiple efforts to isolate and treat friction. Keeping in mind that this is a 'rebuilt' action, I had previously dealt with the tight hammer flanges (not sure if they're Abel or Tokiwa, but definitely not Renner). Note that the work itself was done at least 6 years ago, if not more. The continued friction problems, which made measurements mostly useless, was persisting from the keys bushing. Hardwood buttons had been installed (along with bronz-ish colored balance pins, of somewhat varying diameters). These buttons are not friendly. The cloth is extremely thin, and the wood resists any nuanced plier compressing, so that, when they're tight, as these were, there aren't many options. As evidence of poor fit, the pins had dimpled the resting position of the pin, even with the cloth being as it was. I ironed AND compressed (when necessary), along with using protek on pins (McLube availability?). It was better (at least yesterday) to where I will gather date (complete), from which I can either extract what you would need, or simply send all of it, for your amusement.
My own objective with this piano is to determine the extent of improvement that is attainable, without starting from scratch (new keyboard/frame) but also without wasting time and money.
I'll get back to you.
Thanks
David Skolnik
(917) 589-2625
Original Message:
Sent: 7/14/2023 11:54:00 AM
From: David Love
Subject: RE: Touchweight consulting beta testing
I do have some room for some additional testers if you are interested. Just a reminder, I need people with "on the bench" projects. That can be anything from just hammer replacement to the entire action. You need to be familiar with Stanwood measurement protocols and have the tools to do that. You will be giving me SW, BW, FW on a set of samples. If you have the hammers that you will be using that's great, if not then we can use the old hammer assembly to determine the set up. I don't need to know the action ratio, knuckle hanging distance, wippen weight, key ratio or anything else really (though it helps if I determine your goals can't be met with that configuration).
I'm hoping to either write an article or, better, teach a class on how to do this on your own, it's really quite simple. The method gives you a very simple way to determine your target hammer or strike weights (I can work with either), predetermine and calculate the FW specs from those samples and FW/BW relationship to see if you are in the sweet spot of inertia. In the end you'll get a note for note hammer or strike weight printout and FW printout from which you can lead the whole keyboard. No weighing off entire actions, just a representative set of samples.
Thanks
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
Original Message:
Sent: 07-10-2023 12:59
From: David Love
Subject: Touchweight consulting beta testing
Thanks to those who volunteered. I just want to add that I need an "on the bench" situation, not a hypothetical. I will need you to take several sample measurements and then I will give back to you my analysis and calculated SW and FW for your desired BW. You'll then need to test the outcome. The weights I'll need are SW, FW, BW on a given set of samples, C1 - C8 will be fine. More is always better but not required. Also measure the key ratio naturals and sharps, if they are different, I'll need to know that and by how much.
I will be then be able to let you know if your current set up requires action ratio modification and approximately how much or if you can just go with my numbers. I can make suggestions as to how that should be done though I don't have time right now to do an instructional on capstan relocation. Often this will be a choice of either a particular SW curve and/or knuckle placement if you are determining which parts to use. Otherwise you'll get a SW curve (with numeric data) and a FW curve (also with numberic data) and the BW target that will be produced.
The degree to which BW targets are hit exactly depends on the consistency in the execution in the first place. Balance rail pin line and capstan line are the most critical in this respect. The question of whether to accept a smooth FW curve and slightly bumpy BW yield or vice versa can be discussed but is a choice that usually needs to be made.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
Original Message:
Sent: 07-07-2023 12:04
From: David Love
Subject: Touchweight consulting beta testing
I've developed a spreadsheet which will calculate both smooth strike weight (or hammer weight) curves and front weight curves which will produce a targeted balance weight of your choice. The information will also tell me (and you) if you are in the low, medium or high range of inertia. It's my intention to offer this as a service (for a fee eventually). In the meantime, I'm doing some beta testing right now and so will do an analysis on an action that you are setting up or rebalancing. You will need to be familiar with and be able to accurately measure balance weight, strike weight and front weight on a set of samples from the piano you are working on. A Stanwood style platform for taking those measurements would be necessary. I'll give complete instructions for the data I need and provide you with the data you need=and ask you to verify the results. I've been using this system for several years now and it works but the proof is often doing it for someone else.
People need to already be familiar with these general concepts, I can't teach the whole thing from scratch for this testing.
Contact me privately if interested at davidlovepianos@comcast.net
I can only do 3 at the moment so first come first serve. I may offer more opportunities later.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
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