Crawls Backward (When Alarmed)

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Back Brace Repair on the Circa 1929 Martin Tenor Ukulele

While the glue dried overnight on the crack repair, I had more time to ponder how to approach the brace repair.  Originally I thought I'd use a caul to fit over the brace, and then use magnets on the inside and outside to hold the caul down.

Then I had a better idea.  I would cut a dowel to use as a lever between the brace and the top of the ukulele to hold the brace in place.

I just need to cut it to length and cut a slot in one end so it will fit over the brace.

Getting a lot of use out of my coping saw these days.  I used it to cut a 'V' into one end of the dowel.  I can slip this over the brace to hold it after it's glued.

I opened up the crack in the brace with a flat toothpick, then I used compressed air to blow dust and dirt out of it, then I vacuumed the brace.  We want to try to get as much dirt out of it as possible - not, mind you, that the crack seems to have a lot of dirt in it.

You may be wondering how in the world I'm going to get glue into that small crack inside a small instrument.

Bwahahaha.  I have this way cool syringe I got from LMI.  Notice it has a curved tip which will help position it.  You can cut the tip to suit for more glue flow, but I'm going to leave it small.

And since the glue (Titebond) is water soluble, I can just wash the syringe afterwards and reuse it.

I put glue into the crack.  Works great!

I also put some glue on the surface of the toothpick, and then pulled that through the crack to get glue in the very small crack near the main back brace.

Glued up, squeeze out cleaned up, and the dowel in place.  I thought it might be a good idea to put some waxed paper over the joint.  I don't want to wind up gluing the dowel to the brace!

And the finished repair.

The end of the brace got dented a tad, but it's not bad at all.

You can see the seam from the back crack - after this picture was taken I took some fine grit sandpaper (400) and lightly sanded along the seam to clean it up.

Originally, I had planned to make 2 spruce strips to cleat along the crack - similar to the center brace but not as wide.  The repair is now so solid that I'm not going to cleat it.  I'm not a big fan of cleats unless they're really necessary.  If the repair ever does come apart, then I'd have to cleat it.  But I'm reasonably confident that it's good as is.

 
 
 
 

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