At 9:06 AM +0200 6/13/03, Richard Brekne wrote: >Just commenting on a matter of historical truth there Bill. Fact is >people have >been argueing about whether or not to use them ever since they >popped up in pianos. >They start becoming controversial the moment they replace gravity and mass >evidently. Just hoping to separate fact from factoid here. It's certainly a matter where we need facts. >Which is a totally meaningless figure unless published along with >the proceedures >for measuring it so as to be able to confirm the validity of the >claim. Which of >course doesnt mean he isnt right :) Just means we cant, shouldnt... >accept that >figure at face value. At 4:19 PM -0400 6/7/03, David C. Stanwood wrote: >I set up a key on the digital scale to measure Front Weight. I attached a >rail to the metrology table and hung a wippen, (with very low friction in >the flange), on the rail so that it sits nicely on the capstan. I loaded >jiffy leads on the wippen to simulate the force of the hammer-shank-knuckle >that would normally sit on the wippen. I then held the front of the key >down on the scale by loading the front of the key with a 100 gram weight. >Then I tared the scale to zero and hooked up the spring. The scale reading >indicated the spring was working 17 grams, a figure considered by many, >including myself, to be a safe maximum for the amount that a wippen spring >should be designed to reduce the touch weight by. Then I lowered the >scale by 10.5mm simulating a maximum keydip. The reading changed by 1.5 >grams. When the spring was working 12 grams the reading was closer to >gram. So it looks, according to this sample, like about an 8% reduction in >the working effect of the spring at the front of the key from top of stroke >to bottom... (Incase you missed it..... Don't worry, there's plenty of stuff which gets by me, as you know.) Bill Ballard RPT NH Chapter, P.T.G. "If you jabber like a jabberwocky and if you walk like a jabberwocky, You must be a jabberwocky" ........... two punchy guys +++++++++++++++++++++
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