In a message dated 7/19/99 10:09:27 PM EST, Billbrpt writes: << If you move the bottom posts up or down even the smallest amount, you will change the lost motion by quite a bit. >> I should have called "lost motion" the "capstan adjustment. Assuming that a factory technician overadjusted the tension on the action on the right side, this would have made the capstan adjustment higher than normal to have no lost motion. If the lost motion had been well taken up, the checking should have been very close and there should have also been excessive aftertouch. The jack would have been tripping out somewhere in mid key travel and clearing the butt by an excessive distance. Most new vertical pianos are set up with a short blow distance and plenty, if not a little too much aftertouch but this is done for a very good reason. Natural compression of all of the felts sets in over the first few years and the dimensions become closer to normal by themselves. Keeping the capstans properly adjusted so that there is little or no lost motion should be a routine adjustment that largely in itself keeps the action feeling normal. In this case, I'd speculate that if the support bolts were turned down just enough so that the screws could be inserted and the action installed, the technician would find the treble end hammers standing above the rail. It might also be likely that the standing pattern is not straight across but at an angle with the most deviant being at note 88. Once the capstan adjustment has been made so that the hammers rest normally upon the rail, the technician would most likely find that *no other adjustment is necessary*. To take the tedium out of correcting such a mess, adjust a sample key to find out how many 1/4 turns with a capstan wrench or driver that it would take to correct the *average* adjustment. If the pattern is at an angle, plan to have to make more turns at one end, decreasing to what would satisfy the other end gradually. If the capstans require more than a half turn, it is just as easy to pull the key out and turn the capstan whichever gross amount that you estimate, returning it and moving from key to key while observing your results but not correcting them, altering the amount of turn as you go, then reserving your fine correction to a second pass. It is a lot like doing a pitch raise tuning: one quick and rough pass followed by a fine adjustment. Each one is more efficiently and less stressfully done. In the rare and severe case where you must correct the faulty placement of an action, you need to keep in mind that any turn of the capstan affects the aftertouch and the checking distance (also the damper lift). There is a rather comfortable amount of leeway that you can take with most verticals but there are limits. When changing the position of the support bolts, watch what happens to aftertouch and capstan adjustment even before strike point and damper alignment. Finding the place where the action will work properly *and* you have to make the *least* amount of other corrections (namely capstan) will be the best solution to the problem. Bill Bremmer RPT Madison, Wisconsin
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