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A largish project has landed in the workshop recently that I thought might make an interesting thread. It would also help me solicit opinions and advice as I proceed

On the bench is a Martin OMC-28E that suffered partial immersion in some recent flooding we experienced in these parts.



This was out on a stand and, according to the owner, was immersed about 1/3 of the way up the body before it was rescued.



The back binding and purf is off completely. The back is loose from upper bout to tail block on both sides - it’s still attached at tail block and neck block. There’s damage to the kerfing.

Also, the finish on the back is … not great…



There’s also a significant crack at the Center strip. This is because:



The two lower back braces are off altogether, as is some of the center reinforcement. The other two back braces are 85% loose and barely hanging on.

The neck is and fingerboard are in good order, geometrically speaking. The neck finish, however…



The heel cap has also fallen off at some point and was lost. There’s what appears to be mold spores blooming under the peghead finish too.



The soundboard bracing appears to still be well adhered to the soundboard. The soundboard finish is also in ok shape, except in the area of the binding, which is loose.



Finally, due to the loose back and bulging sides, the neck angle has collapsed:



So I’m looking at bracing and crack repair, regluing the back, rebinding, the likelihood of a partial refin and, assuming returning the back/sides to their correct location doesn’t greatly improve neck angle, a neck set and associated fretwork.

This will be a slow, long-term project that I squeeze in around the regular flow of jobs in my shop. I’ll try to post updates as regularly as I can.

To kick things off, since the back binding is toast and the back itself is 80% loose, I’m considering whether I should just remove the back altogether to facilitate repairs inside the box. I welcome your advice and input!

The few I’ve had come through the shop with that many problems all got the back removed. Makes it a lot easier to fix all those issues inside the box, in my opinion. The trade off is having to reattach the back which is a bit of a pain.

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Steve Smith
"Music is what feelings sound like"

Yeah, Josh - Pop the back and do what you gotta do. Wouldn't hurt to let it dry some more, just to be sure. Big job, long hours on the bench, should be a big paycheck when it's completed. Good luck!

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"Act your age, not your shoe size" - Prince

I've had a D-35K in my shop for 10 years that suffered similar damage except someone stashed it away wet so the back's interior was full of mold. Took the back off and slowly started putting it back together whenever I had time. Finally about ready to close the box. I think the finish on mine will be acceptable as is, but yours may need an overspray. Or not, and just let the ugliness tell the story. Except for the neck which definitely needs some finish. Good luck.

If I'm seeing that correctly, it looks like the sides tried to straighten themselves at the waist. You've got your work cut out for you!

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formerly known around here as burbank
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http://www.patfosterguitars.com

Yes it could be tricky. I think I’ll need to cobble together some kinda rube-goldberg clamping and spreading arrangement to bully everything back into place.

If I were trying this (with my minimal skills) I'd make some form to fit round the rim and get it in place, with the sides lined up properly, before I removed the back. I think I'd also clamp the face and neck down to a board, to keep the top geometry in place

I suspect once the back is off it will all want to move around somewhat, and I'd surely manage to replace the back in a way which achieved 1/2 inch action at the 12th if I didn't do this!

If I have to take a back off I make a cardboard outside mold. They usually want to spring out of shape like that.

Different situation, but seeing that cardboard mold gave me a good idea for a situation I've got - thanks for the brain wave!

Clever repurposing of what most would consider trash.

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"Act your age, not your shoe size" - Prince

Here is my Rube Goldberg jig for side alignment. It is bolted to the top of my guitar cradle for cutting binding rabbets. That is a 70's era D-18 that is currently in the jig.

Great ideas, thanks. The sides may already be distended too far from their original position for a cardboard mould in this case but I love the idea.

Barry, I think I will be making a jig similar to yours before this job is over.


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Wow! that's awesome Barry.

I wonder if I could squeeze a few more bolts in there.

Sure - - - the brackets each have two threaded holes for bolts and only half of them are filled.

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Peter Havriluk

Barry, I assume you drilled and tapped all those holes yourself and there isn’t some convenient source of brackets with pre-tapped holes at just the right height?

Josh....DIY

I thought so!

I bought an angle iron (aluminum actually) cut it up and drilled away.