<HTML>That would depend on how the new board is being made.&= nbsp; If you are sending the board out to be cut and ribbed, then follow the= manufactures specs.  If you are ribbing it yourself then it would depe= nd on the method of pattern making you are using. Sometimes SBs can simply be knocked out with a sledge and a 2X4, however I h= ad one recently which would not come out for any thing, so I cut it out usin= g a die grinder and Spurlock's SB shimming tools and cut along the perimeter= .  For me it doesn't matter how the board comes out, I use it in whatev= er condition it is in to create an approximately sized template which goes i= nto the cavity to be cut to exact size using a router. Just a word of encouragement and warning: I found SBs to be no more complica= ted than doing action work, just a different set of problems and geometry's.=   The biggest difference is that mistakes are darned expensive to fix! = Measure, think, fit, think, measure again, think, fit, come back tommorow an= d think some more.  Then get off your back side and put the sucker in!&= nbsp; There are many very good articles dealing with installing new boards in the = Journal, in fact there is a reprint book just dealing with this issue. = I found these more than a little helpful. I would be happy to help off line if you would like to give a call. Andrew Remillard ANRPiano.com ANR Piano Service 2417 Maple Ave Downers Grove, IL  60515 630-852-5058</HTML>