Jenneetah wrote: > At 7:44 AM +0100 9/1/04, Richard Brekne wrote: > >> The knuckle core seems to be very much t ilted towards the hammer... >> which changes the shank ratio from the intended one, in this case >> increaseing the leverage of the shank. > > > What ever its positive effect on shank ratio, it weakens the knuckle > core as a structural element. The jack's thrust is no longer being > received by something mounted normal to the shank, and this situation > over grows worse. He he... I dont think I said increasing the shanks leverage was a positive thing.... It should be what it should be... tilting it forward is a classic slop mistake. That said.. maybe the photograph just plane gives a erroneous view of the situation. > > It also confuses technician who continue to use it as a guideline for > setting jack position under the knuckle. As the jack is being set to > something other than normal, it is being pulled away from the normal > line of force. Ric, you spotted right off the un-square knuckle core. > The jack which is sitting well behind the knuckle's center could > easily have been put there by a technician using the core as a guideline. Agreed... and this is just one of several problems this kind of thing can incur. It introduces a whole bunch of touchweight inconsistancies... as one simply has to believe any angling of the knuckle is more the result of random error then purposeful design. > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives > Cheers RicB
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