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I’ve just had a Wenge body guitar returned to me that I made a couple of years ago with one crack in the back and the beginnings of cracks in both sides around the upper bout.

The owner has attempted to repair the back crack with superglue as a DIY repair, but it’s separated again.

Now, I’m no repair expert, and I’d be eternally grateful for advice on how to proceed.

My initial thought is clean the superglue out of the back crack, glue with titebond, cleat the inside and clamp with magnets. Am I thinking along the right lines?

As for the side cracking, I’m at a loss as to stabilising them. Has anyone repaired similar cracks before?

Thanks in advance.

Steve.

The problem is that the CA wicks into the wood pretty deep. Every repair is unique and it's hard to make a judgment call with no pics or even better seeing it in person. Titebond would have been the better choice for your customer to use first but what can ya do about that now? You may have to saw cut out the crack to fresh wood and inlay a splint. You might be able to get away with using CA since it does stick to itself well. Or a black/brown epoxy might just do the trick and fill in any voids if necessary. I glue up my back panels with epoxy so that's probably the direction I'd go in personally.

I have had success repairing cracks on curved surfaces by putting a piece of surgical gauze tape over the crack on the inside and soaking it in CA. This critter has no bracking inside and would be almost impossible to fit cleats but the gauze tape worked perfectly



Once you get the crack closed and stable you can figure out what kind of cosmetic repairs you want to do - I often only drop fill the crack and scrape it back. Sometimes I'll rub parafine along the edges of the crack to keep CA from flowing out onto the finish.

I've also learned a little trick when applying cleats - if it is a flat surface inside the guitar I put the cleat on one jaw of a clamp by wrapping masking tape back on itself to make sort of weak double sticky tape. I'll also put a piece of tape on the screw part of the jaw to keep it from turning (not shown in this picture)



When I reach inside the guitar I line the outer jaw with the line of the crack (with some sort of caul) - then I know the cleat is centered over the crack on the inside. Snug up the clamp, when you get ready to remove it the masking tape releases easily



(The top on this guitar had been bumped - was both cracked and separated at the side joint. Used Titebond to get some working time)

Wow, that’s great. That gives me a little confidence to get on with the repair.

The gauze fix sounds perfect.

It’s a tru oil finish so I’ll just rub back and apply some more.

Thanks again chaps.

Do you know the cause of the cracks? Were they a result of damage or did the guitar dry out?

_________________
Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

If the cracks are relatively tight you can use a color matched powder stain Van Dyke brown?) and CA to fill any small voids, by first wetting with CA and then sprinkling powder stain into the wet CA. Neatness counts - keep the CA only in the crack as much as possible.

Not rough handling or apparent trauma as far as I can make out.

The guitar had been to university halls and gigged in pubs, so probably subject to undesirable humidity. The owner is a student.

The cracks are very tight and the wood dark, so I’m not too concerned about disguising the repair.

Many thanks for the advice, Clay.