..... which is what I've decided to "dub" this process .... ( And which, because I'm feeling particularly generous today, I won't even try to patent or license !!! ) A) Make a Mylar (TM) or paper pattern of the bridge sweep. B) Feed it behind the posts, lined up with the soundboard buttons, marking on it where the ribs cross. C) Trace it to a plank. ( Like a 2x8 from the lumber yard . ) D) Drill straight through the plank (3/8" holes ) on the rib marks, and squeeze threaded inserts into them, and run matching, long, 5/16" , full-thread bolts through them and out the other side. E) Place it all against the back posts, so the tip of the bolts are right over the ribs, where they cross the bridge line. F) Make your laminate out of whatever you feel comfortable with, and place it along the top of the rib spine. Place a block-of-wood caul on top of that, and run the bolts out until they press the caul, laminate, rib, rib spine togetrher, bowing out the board. Start with ribs toward the middle, and work toward the ends of the bridge. ( Toward the treble first, probably. G) Check to see what sort of bearing you're getting. H) When you have the bearing you want ( and probably a little more ) wrap tape around the bolts where they go through the plank, to mark how far they're threaded in, and back them out. Then put glue on the laminate, and put it back under the block caul and squeeze everything together again, to the point the bolt was turned in, before. Let dry, remove, and check your bearing again. If it were OK to use some sort of close-grained wood instead of sugar pine, thin laminates could be useds, and added if the bearing were inadequate. I ) Check for load bearing, fix cracks, restring. Peace, Thump ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
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