At 9:50 PM +0200 12/14/02, Brian Lawson wrote: >Hi, if you take some keys out and activate the action with your finger is it >still sluggish? else, is the front rail pin going too far into the mortise? Brian is getting you started with troubleshooting. I'd: 1.) put your hand on the backsides of the keys in an offending neighborhood (a better way to set them aside in the troubleshooting isolation), step on the sustain pedal (to remove damper spring pressure), and with the other hand, lift the wippens from the front-side, remove your hand and watch the wipps and the hammer butts drop back. That'll tell you that the problem is not in the keyboard or the damper levers. 2.) Lift a set of wipps part-way up (half-blow for the hammerheads) with one hand and with the other, gently push the hammer heads the rest of the way up to the strings. Now let the hammers fall back, and watch for sluggishness there. That is the second half of the hammer blow, where gravity has the least effect on tier return. You can do the same test for the first half. Either of these will now eliminate the hammer flange pinning as the source of the friction. 3.) With the sustain pedal on, hold a section of hammers up to the strings, with the other hand, lift individual wipps until the jacks hit the butts, release and watch for slow returns there. This tells you it's in the wipp flange pinning. 4.) Key friction is checked with the action out. First the front bushings: check for at least 1mm of lateral play with the key at rest *and* at the bottom of the dip. The center bushings should also have that same side-play. Better yet, lift the key perfectly parallel with the balance pins. After 3/8"-1/2", the mortice will clear the pin. Now how does the lift of the key feel (once cleared the center bushing). Continue lifting now that the only remaining sliding contact is the pin in the balance hole. How much lighter does the key feel once you've finally lifted it completely off. (Another test for the balance hole friction, assuming center bushing friction is fine, is lifting the key at rest from the front 1/8" upwards off the balance rail felt punching. Does the key fall back of its own weight?) You'll see buzzards circling overhead when the friction is not in the individual components but in their combination. Bill Ballard RPT NH Chapter, P.T.G. "When you do, you will" ...........Albert to his charge Chris, in "What Dreams May Come" +++++++++++++++++++++
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