(string instrument with a pear-shaped body and a long neck, played with plectrum)Ĭ3 – E6 (tetrachordo), D3 – E6 (trichordo) The first time I repaired it, I used a slightly softer epoxy and carbon fiber rod, set not quite as close to the edge of the nose, and it pulled loose after a few months.Greek plucked stringed instrument Bouzouki I had to do this on the bow I mentioned above, and the repair has held now with no problems for several years. If the epoxy is hard enough, this will work. If removing the tip plate isn't an option, then you'll probably have to make a slightly oversize hole in the mating pieces that allows enough clearance with the dowel to take care of any position/angular mismatch in the holes, then rely on the gap-filling abilities of the epoxy to fill the gap. If the tip plate also needs replacing, the easy way is to remove the old tip plate, glue the broken pieces back together, drill up through the mounting surface for the tip plate (mark the drill so you can see when you've reached the right depth), fit the dowel and epoxy it in place, trim it flush with the tip plate mounting surface, then install a new tip plate. The tricky part is drilling perfectly matching holes in the two sides of the break to hold this splice. A piece of pernambuco from an old, unrepairable bow might also work. I've had better results with a piece of very, very, very, very hard wood (I used osage orange, the hardest hardwood in North America) to make a dowel about 2/3 the diameter of a toothpick. I've tried a piece of carbon fiber rod, which has the required strength, but has difficulty getting enough shear strength in the bond along its sides to keep from pulling loose. You're going to need to fit a splice in that area, parallel to the edge and as close to it as possible (but ideally still hidden inside, out of site) that can carry that tension load. The most critical area of the tip is the portion under tension, right along the "nose" edge of the tip. If it bends at all without breaking, and holds a bend at all after you release it, it's too soft. If you mix a batch on waxed paper about the size of a quarter, maybe about 1/16" thick, let cure at least a day and then try to fold it in half, it should snap with a clearly brittle failure. Soft epoxies are optimised for peel and impact strength, while hard epoxies are optimized for tensile and shear strength. Hide glue might be made to work, if the splicing parts are fitted perfectly, and have enough surface area, but it's going to be very tricky, and the first time you try to use the bow in damp air there's a good chance it could come apart. ![]() Hard epoxies work OK (make a test sample to check this before using it on a bow). There's an astonishing amount of stress in the tip, and the repair has to be very good to have even a remote chance of holding.ĭo not use glues that dry "soft" and rubbery, like some forms of epoxies, or that can creep under load, like white glues (Elmer's) or aliphatics (Titebond). One of my favorite bows is one with a busted tip that a friend gave me, and I repaired. A broken tip is considered to be a "fatal" injury by many, sort of the bow equivalent of a bad bass bar or sound post crack in a fiddle, but they can be fixed.
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