Hi list, I've been doing some reading, at least what I could find at my fingertips, on action geometry, and although I can find a lot of general stuff, and a lot of theory, specifics aren't quite as easy. I've changed out the wippens and shanks/flanges/knuckles on a well known action. The new parts are Renner and are the closest I could get to original dimensions. However, they are NOT identical. The wippens are shorter in length by about 3mm, the variation appearing to be mostly out at the jack end of the wippen. When I leave the action spread at 4 1/2", as was the original, the jack doesn't have room to clear the knuckle before it burys itself in the felt stop at the end of the wippen. I can't seem to get a picture in my head of the negative effects of shortening the action spread, or if I'm doing anything wrong at all. It's been drilled into us tech types that the action spread is sacred and NEVER to be messed with. Well, I had to do something, 'cause the way it was, it wouldn't work, period. What has seemed to work in this instance is moving the hammer rail forward about 3mm. (Another possibility would have been redrilling the hammer rail to put the flanges a few mm farther back <towards the back of the keys>). I just wanted to run it past someone else who might have seen this stuff before just in case I'm overlooking a disaster looming on the horizon. Any insight? Thanks, Brian T. ===== Brian Trout Grand Restorations 3090 Gause Blvd., #202 Slidell, LA 70461 985-649-2700 GrandRestorations@yahoo.com __________________________________________________ Do You Yahoo!? Yahoo! - Official partner of 2002 FIFA World Cup http://fifaworldcup.yahoo.com
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