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This Martin uke is un-numbered, but dates from some time in the 1920s. It's a model 2M, which means that it has front binding but not rear binding, and has mahogany back and sides rather than koa.
It's in original condition, but has recently acquired a nasty side crack. The tricky part of repairs like this is to get the two edges aligned - mahogany tends to splinter and it can be difficult. Gluing up the crack before the edges are properly aligned is asking for trouble!
I used the tip of a scalpel blade to ease the two sides into place and then clamped them using some side crack clamps. I made my set years ago, but Stewart Macdonald now make a very useful version. A cleat wasn't necessary in this case, so I used a non-stick caul inside. Hide glue was used for the repair. With a very thin coat of shellac the repair is almost invisible - one of the best I've done. Shellac is a good option because it's less glossy than cellulose, and blends in with the original finish very well.