Ron: 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? 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. Why would this be a more reliable method (though, you are right, I have not experimented with the go bar method). BTW, what would be "dangerous" about the use of go bars this way--I think you mentioned that in a previous post. David Love davidlovepianos@earthlink.net > [Original Message] > From: Ron Nossaman <RNossaman@cox.net> > To: <davidlovepianos@earthlink.net>; Pianotech <pianotech@ptg.org> > Date: 7/25/2003 10:22:29 AM > Subject: Re: soundboardinstal again > > > >I believe go bars can be calibrated based on thickness, type of wood (ash > >or hickory) and length. You have to have a way of setting the piano at a > >controlled height below a top deck. Then by using go bars of a specific > >length differential between the top of the bridge and the top deck, and the > >go bar itself, the amount of force given by each go bar can be determined. > > > > > >David Love > > Don't just believe it, try it and find out. See if you can pre-determine > the final pressure from a bowed go bar pushing on a deflecting soundboard > when they reach equilibrium. You could be famous. > > Ron N
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