Composite body crack repair

[basil_555]

Hello. I have just acquired an Ovation guitar copy made by Stagg (composite body). I bought if from Ebay, but when it arrived, I noticed a significant crack on the back (as you can see on the photo). What do you think is the best way to repair it? How should I then remove the excess of the glue and make the crack invisible (rubbing in some black powder?) The surface is very rough! Thank you.

[D. Churchland]

An interesting condundrum.

It won't be invisible, unless you can replicate the texture on the composite which is highly unlikely.

The best thing I can think of is to develop a clamp method to close it. Epoxy or superglue would be your best bet to glue it.

I wouldn't worry too much about excess glue/epoxy on the inside, I would simply use a scraper on the outside to get it somewhat level with the surrounding composite.

You don't have many options with composite. You can fix it, or look at buying a new guitar which might save you alot of trouble and time. Get an all wood guitar if you do, you'll find that repairs are much simpler that way.

[cooper59]

if the seller didn't disclose the crack you can get your money back from eBay.

[Frank Ford]

Offhand, if I were expecting to try to fix this one, I'd get some cyanoacryate in the crack and hold it shut until the glue set. Then, working from the inside, with the preamp components removed, I'd scuff sand the interior area well with 80-grit sandpaper to prepare the surface. Finally, I'd saturate a piece of canvas with slow set epoxy, and pave over the entire area for a couple of inches on either side of the crack.

[phavriluk]

That guitar looks to me to be 'composite' all right, wood and moulded plastic of some kind, by the looks of the crack. If I was doing the repair, I'd like to find out whether the body material responds to solvent cements, and if so, I'd get my clamping and gap closing tested, and then use that solvent cement in the crack and clamp it up for a day or two. And then reinforce the inside of the crack as suggested in another reply. I think, and the word is 'think', that a crack repaired with a solvent cement is likelier to not crack again as compared to a crack repaired with CA.

[Earl49]

First thing I would do is to drill a small hole (1/16" or so) right at the end of the crack, to stop its progressing any further. A crack is a major stress riser / concentration, and a relief hole would reduce that tendency.

Repairing the crack itself has been covered pretty well already. Is there any way to find out more about what this composite is (from the manufacturer)? That would give clues about proceeding with the repair.

[Rockysdad]

Originally Posted by Earl49

First thing I would do is to drill a small hole (1/16" or so) right at the end of the crack, to stop its progressing any further. A crack is a major stress riser / concentration, and a relief hole would reduce that tendency.

Repairing the crack itself has been covered pretty well already. Is there any way to find out more about what this composite is (from the manufacturer)? That would give clues about proceeding with the repair.

+1 on this response!

[Hot Vibrato]

I like Frank's response, but my first thought was that I've seen fiberglass resin for sale at the auto parts store, and that might be a good way to reinforce it from the inside, although I have no experience doing that sort of thing.