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Crack through violin low G tuner hole

Steve,
       I have a crack through the low G tuner hole of my violin. Mainly on top. It is not all the way through yet. About 1/2 inch top and 1 inch below. Will it get worse and should I fix it, and how. I thought of drilling in to the side above and below the tuner hole and putting screws on each side and clamping the crack and preventing from going any further. Then putty over the small crew heads and lightly finish.
Any recommendation would be appreciated.
Bart
 
 
Bart,
       Don't put screws in it. Metal is stronger than wood, but the joint between the wood and the metal is much weaker. Removing wood and replacing it with metal can put a pinch right where you need it, but at the expense of the strength of the whole peghead. A good glue joint is stronger than the wood.

       First, close the crack. Remove all the pegs and strings so that you have a clear work field. Study the crack closely. You must be able to close it with moderate clamping pressure. If it won't close easily you must re-fit the crack, with an Excell #11 knife or the like. If the clamping pressure used exceeds the strength of the glue to hold the crack closed, it will re-open. The proper glue for repair on a violin is hide. It dries very hard and carries vibrations well, and comes apart easily when needed. Slow drying Epoxy (not 5 minute) is best for this job. It dries very hard and has a long time to capillate deeply into the surrounding wood. Vibration carrying and re-open-ability are not necessary for this joint. Mix more than enough in a jar lid. Stir it with a toothpick very, very thoroughly. Put a lot on the crack and then pump the crack open and closed until glue comes out the other side. Clamp it. Wipe off all the excess epoxy with kleenex and mineral spirits. Epoxy cleans up easily when it's wet. When it is dry it must be filed off. The clear epoxy will lens any tiny gap in the joint. If the crack is not perfectly closed, put a little color powder into the epoxy.

       The normal reason that a peghead cracks is that the pegs don't fit. Luthiers have matched shavers and reamers, to true the roundness of the peg and fit the hole so that the pressure of the friction fit is distributed evenly to all parts of the joint. If the taper is wrong, or the peg out of round, the peg will put all its stress into the spots that do contact. There is a fair chance that with the strength of the epoxy and the peg properly refit, you might be done. It would not be crazy to string up the violin and play. If it cracks again, repeat the above steps and then move on to reinforcing the joint.

       Buy some boxwood bushing blanks from a luthierie supply company. These are conical pieces of boxwood. Ream out the cracked and glued hole. Glue a slice of boxwood into the hole. Re-drill the peg hole so that there is at least 1/16" of new wood around the peg. Be sure that the grain of the new wood is at least slightly cross-grained to the old crack. It is also possible to use cylindrical boxwood or maple, packed into a straight cut hole. It is just a lot harder to do. Trim it, scrape it and match in some finish. Oil varnish with color powder is the right thing to use. Much faster and nearly as good is flake shellac with color powder.

       To do this job right you will need a couple of hundred dollars worth of shavers and reamers and clamps and finish. This may be a job you will want to take to your luthier. And, by the way, check the fit of all your other pegs!
Steve Mason

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