I have been reading some recent posts on touchweight and related subjects, and I detect much confusion that would be impossible for me to clear up in a single post on this list. I'll just make a few general statements. In Bob Hull's latest post, his measurements indicate reasonably even strike weight, although it might be a tiny bit heavy in the high treble. Down-weight, up-weight, and balance-weight are all over the map. I don't see a column of numbers for the friction component, but I suspect that's where the problem is. Here's how I do it: I deal with the friction first. Keys first, absolutely, before anything else, then the various action centers. There is no sense fretting with action centers if the keys are binding. To do a thorough job checking the keys, the stack must of off. You will find things you can't find if the stack is on. After you have the keys all in good shape, deal with the action centers. Don't overlook mundane things like rep levers rubbing on adjacent knuckles, and stuff like that. If the hammer weight taper it reasonably even, the strike weight will be also. If that's the case, and unless someone has been messing with the action geometry, and it looks to be in order, I weigh off for balance weight, with perhaps a little give and take here and there if there is reason to do so. Friction will go up and down as the relative humidity changes, and so will down-weight and up-weight, but balance-weight will stay the same. If the friction component is fairly even; if the strike weight taper is smooth, and if the action geomerty has not been screwed up, the other measurements will fall right into place. Unfortunately, I find cases where capstans have been moved around, and other things done to the action, when that was not the problem in the first place. It's very doubtful that an S&S D has the capstans in the wrong place, but if that is the case, it's a major problem. Being poorly aligned with wippen heels is more common. I would do some very careful checking before I started messing with the action geometry of a premium-quality grand, but I would do it, and have done it, when I have found such a problem - which isn't very often. More often than not, the problems I find are those that come from the fact that somewhere along they way - at the factory or somewhere else - someone did a weigh-off while uneven frection was still present. When that happens, you may end up with fairly even down-weight, but everything else will be all over the map. That's the way I do it, and unless someone has screwed up the action geometry, or it was flawed in the first palce, it works every time. Sincerely, Jim Ellis
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