Tom, I have been doing such repairs for almost 25 years. The best way is to remove the bridge pins and then "V" out the crack to half the depth of the bridge pin holes. ( I use a very sharp, large "Buck" knife for this "V-ing"). I then fill the "V" with "Steel Epoxy", (Devcon or Duro brands, found at the good hardware stores), then re-insert the bridge pins while the epoxy is still soft. The tool(s) of choice is(are) artists palette knives. Smooth and build up the steel epoxy to above the top surface of the bridge. Wait 3-4 hours until the epoxy is in a consistency of modeling clay. Carve the epoxy to the shape needed, (ie notching, leveling), with a tool called a "spoon gouge". Let set, (NOT DRY) and do the final shaping scraping, etc., for a perfect reproduction shape. It is advised that you NOT color the repair with a felt tip pen. The solvent in felt tip pens is alcohol and is also the solvent for epoxy, so refrain from being too neat and tidy. (don't ask how I know the felt tip pen juice breaks down the epoxy!<G>) I have hundreds of these repairs, out there, and haven't had a failure, as yet, (knock on soundboard). <G> For "hair-line" cracks repair, it is best to use a clear, medium set epoxy and an old high watt soldering iron. This is done with the bridge pins left in the bridge. First, seat the bridge pins to their proper position, with a #3 nail set. While you are doing that, have the soldering iron plugged in and heating. Mix small batches of epoxy. Apply the epoxy to the opposite side of the bridge pin with a drop on the tip of a wooden, round cocktail tooth pick, while heating the bridge pin with the soldering iron. This will take a bit of practice....when the epoxy starts to be drawn into the hole/wood, immediately remove the soldering iron...go to the next pin. Once you have gotten all the cracks filled, wipe the excess off with a rag. (final clean up should be by scraping after the epoxy has set) DO NOT be tempted to clean up with Lacquer thinner! This will degrade the bond of the epoxy! Do clean up your tools/self with lacquer thinner, then immediate soap and water. (Please, no comments about the toxicity factor, ALL!) I know this is somewhat complicated to read, but the process is simple and works very well. Happy 2002 to all! Regards, Joe Garrett, RPT, (Oregon)
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