>I was basing my assumption on an article I read some years back by Bob Hohf >(I think) about bridge recapping. He used a go bar method for prestressing >the bridge prior to setting bearing. In wedging the board, you are aiming >for a certain amount of deflection at each strut, right? You're going more for a certain amount of stiffness than deflection. >Wouldn't the >amount of pressure on the board based on the amount of deflection vary >quite a bit based on the location of the struts and flex in the struts, >among other things. Yes, to some degree, though I don't think strut flex will have much - uh - bearing (sorry) on the process. Actual soundboard deflection will vary depending on the board stiffness. Some boards will be stiff enough at a relatively small deflection, some will require more. Many an old board has been restrung that wasn't stiff enough to support the bearing put on it and still have positive crown. >Why would this be a more reliable method (though, you >are right, I have not experimented with the go bar method). Because with wedges you can feel what you've got in board stiffness. and can compare stiffness with remaining crown. Ron N
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