This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment _____ From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On Behalf Of Erwinspiano@aol.com Sent: February 18, 2006 11:31 AM To: pianotech@ptg.org Subject: Re: laminated ribs In a message dated 2/18/2006 9:26:00 A.M. Pacific Standard Time, rnossaman@cox.net writes: Dale wrote > Ok Now I,lm confused. If were only trying to support only 400 to 600 > lbs. of down bearing force as Del inferred recently or whatever one > calculates this to be, then what's all the fuss about. My loading of new boards these days is typically half again over 600 lbs. Ron, so you are saying a 900 lb bearing load is probably an in the ball park average plus or minus for various sizes of pianos & string scale tensions. Then my comment a couple weeks ago about bearing being 1000 lbs or more depending on who you ask wasn't that far off this figure even though Del disagreed with that as being "excessive." Consider a basic scale of moderately high tension. Say 40,000 lbs. overall. With this string tension 1,000 lbs of string downforce equals 2.5% of scale tension. That is quite a lot considering that most companies are claiming string downforce more on the order of 0.5% to 1.5% of string tension (which would be 200 to 600 lbs). I thought I was setting my initial string downforce pretty high at around 1.0 to 1.5%. I don't like thinking about what I'd be doing to a board loading it up to 2.5%. I can't imagine it being happy enough at that level to want to stay there. Del ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/56/d5/ea/6f/attachment.htm ---------------------- multipart/alternative attachment--
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