At 08:12 PM 3/31/98 -0700, you wrote: >If my memory serves I believe a carriage bolt has a round head with a >square shank. The purpose of the square shank is to prevent the bolt from >turning as the nut is tightened. My concern would be that the square shank >might start turning in the wood, which would prevent the nut from being >tightened as much as you would prefer. I would suggest using a hack saw >to place a slot in the head before installing. You could then use a >screwdriver to hold the bolt while tightening the nut if it became >necessary. > > dcp@sosinc.net >Don Price If the hole that is drilled all the way through the back is too large, the carriage bolt will keep on turning in the hole. I found that out by mistake! If that happens, you can put epoxy in around and underneath the head of the carriage bolt so that when it hardens, it will stay in place without turning. Also, be careful not to tighten the nut too much! It is possible to strip out the threads on the carriage bolt so that the nut can't be tightened and also can't be removed! Ask me how I know! Another time I was just finishing up the repair, and tightened one of the nuts too much, and the carriage bolt came shooting out of the back of the piano and made a dent in the wall 3 feet away! Maybe grade 8 hardened bolts would be in order? :-) Sincerely, David David A. Vanderhoofven, RPT #pianotech page: http://www.clandjop.com/~dkvander/ircpiano.html New web page for the Joplin Community Concert Association http://www.concerts.joplin.com
This PTG archive page provided courtesy of Moy Piano Service, LLC