---------------------- multipart/alternative attachment Ric When you read John Hartman's articles on the "Effects of down bearing" on tone the method he describes in his 4 th installment is the way many people I know personally set up bearing load in their new boards including me. (old boards too with variations) It is an old factory method used by Steinway & others to set bearing in the factory. It doesn't take a genius to do it, just careful consideration & attention to details including the approx EMC at the time one is setting the bridge heights for bearing. The description of condition of bearing in the 1960's Stwy L I wrote of in a recent post & the toanl results I routinely encounter in my own set up this way tells me that this method is quite accurate and capable of finding the sweet spot in boards with new or adequate crown. Putting a number on it nice but it won't change my procedure or outcome although inquiring minds always demand to know including mine. In a board with little crown 200 pounds might be all you could apply safely so a consensus will/should probably only apply to new boards. Oh yeah consensus....? here?? right!!!! Reading the articles will answer the question you ask in your paragraph 2 Happy reading or maybe you did that already? Dale Given the fact that I am about to sink my feet into this kind of thing seriously for the first time... I shore nuf would like to see some semblance of consensus formed here. Strikes me that a range of 200 to 900 lbs of down bearing on the soundboard is a rather huge window. Could you guys please go a bit into how each of you arrive at your figures ? And I would also like some words on how typically this load is spread over the panel.... along with a few words about how one designs ribs to carry the load as it varies over the board. Also... assuming the greatest load is up in the treble (which I seem to have got into my head is the case) how likely is it that given a board with grain going perpendicular to the bridge with the longest ribs then being in the treble area, would be able to hold up against the minimum figure arrived at above. Thanks RicB ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/d9/57/28/7b/attachment.htm ---------------------- multipart/alternative attachment--
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