Terry Sorry I forgot to address that point. The answer is yes as to measuring the string gap at the string rest/aliquot How large a piano is it and how old? I think I'd like to know that before saying anything hard and fast but if the wood looks sound and you have new bearing values I'd push it pretty hard And always keep the dmp chsrs on.! I know what does that mean? To answer that fully will require finding John H's. articles but to cut to the chase the method I and many of my colleagues use is called a pre-stressed method of setting bearing and is easily adapted to fit your situation as well. This method requires that the board be at some reasonable R.H.(which it is ) then installing the plate and securing at the block,nosebolts and a few places at the rim. At that point pull a string thru agraffes over the bridge and see what you have in the way of a gap between string and rest . Lets just assume at this point your bridge is a perfect original bridge and the height is good (which in your case is possible since your bearing is mystically so good). Good meaning the too tall bridge will provide adequate bearing. The info gained from the next step will lead you to know if you will lower or raise the plate shim or unshim string rest or install new bridges to get what you want . Cut 4 thin/small maple wedges and starting at the central strut wedge one between the top of the bridge and the bottom of plate strut while pounding downward on the bd. near the strut . Repeat at each strut location then return to first and repeat cycle of pounding to ensure even preassure on the board. As your pounding ( Pounding is not violent just firm and yes you do develop a feel for this and each boards resistance is different and will pre-compress to varying degrees) Once the bd. is compressed retake string thru agraffe. readings and over bridge. The gap I want to see is roughly 2.5mm in the top treble 2.25next section down nd 2ish in the middle to bottom. Please these are not hard and fast and there. are variations we all use depending on the sit. and are intended as a good starting point and one I feel is safe for your siuation. Usually the amount the board sinks is fairly predictable. I.E. 3 m.m. at the central strut 2 or so at next ten /treb. and 1ish at the top. and 1 or 2 on the bottom. Do not over pound the bottom it needs to flex as it's near the rim glue joint Hope this helps and if I left anything crucial out ( like a lot o stuff) Buzz me another post.This should get you started Dale Erwin P.S.Wish all new/young? techs. showed your persistence!
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