Here are a few comments following the latest posts on related subjects. Richard, I was using the term "touch-weight" to refer generally to the static measurements, "doun-weight", "up-weight", "balance-weight", and "friction", of the total action (minus the dampers) as these appear at the key front. I do know what "balance weight" is. We say "weight" because that's what we use to measure these forces at the key fronts. Paul Legard, Paul would like all the confusion to be removed from this discussion, and for us to provide him with a simple soultion for optimizing an action. Paul, try this. 1. Start with a well-designed action. Re-designing an action is not what you are wanting to do. 2. Use hammers that are uniformly graduated from bass to treble - no large or sudden variations in size or weight along the way. That will give you hammers with evenly graduated mass, bass to treble. 3. Use the recommended parts for that particular action. We assumed a well-designed action to begin with, so maintain the original design, ratios, spread, clearances, etc. 4. Check everything for friction, beginning with the keys alone, befure you go any further. Keys free to move - no binding - very tiny bit of side-play at the front bushings - barely enough to feel - no more than that - no side slap - no binding - no "pulley keys". Check everything else. Everything snug, nothing loose, but nothing binding, jack centers absulutely free. Don't worry about whether the shanks are round or octagonal. It won't matter, as long as you stwy with the correct dimensions and high-quality parts. I'm talking about the keys and action, not the back-action or dampers. That's another matter. 5. Do a preliminary action regulation. Double-check for any possible problems, especially any tight centers or bushings, or anything loose. Deal with all that stuff first. 6. Weigh off for even BALANCE WEIGHT (down-weight + up-weight / 2). The actual balance weight I aim for will depend upon what the piano owner wants. If you have done the preliminary things well, you will find that there won't be any big differences in balance weight and up-weight from key to key after you check the down weight. There will always be some. But if you aim for even balance weight, you won't be way off when the friction changes, as it will surely do, sooner or later. If you follow this routine, you will end up with an action that has an even response from bass to treble. But if you start with hammers that are not uniformly graduated from bass to treble, and friction that is not consistent, and then try to compensate for it with the key leads, I can assure you that you will end up with an action that does NOT have a consistent feel from key to key. David Stanwood has a patented system for doing this that we have all read about or seen. I have my own system, different from David's, that I was privately developing when David first come on the scene. Mine is still under development, so I won't go into it right here on this list. I have not yet decided what to do with it. But Paul, if you will follow the simple procedure I outlined, you will end up with an action that is consistent from bass to treble, and you will not infringe upon anyone's patent claims. You will just be doing what has already been done for years, but you will be doing it well. From time to time, some manufacturers have not been as careful as they should have been. The problems I often find in old pianos are: 1. The hammer weights were not uniformly graduated to start with. 2. The friction was not uniform to start with. 3. The factory tech tried to compensate with key leads. The result was that the down-weight might be even, but the key-to-key action response would not be even throughout the dynamic range, and no amount of regulation would make it so. Furthermore, when the friction changed, the down weight would be uneven. Sincerely, Jim Ellis
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