Here's a rare bird, that got the top punched in during delivery. Can't seem to get the pieces of the top to lie flat, as they are wedged together. Am afraid of breaking off splinters and making things worse. The back came off cleanly, and is very thin, as is the top. This mandolin is extremely light in weight. Wanted to ask the folks who know, before I screwed this up.
You mite just as well replace the top as that thin top will never stand the presure of the strings. That is likely what happend to it in the first place.Bill............
Top was in one piece with two repaired cracks, box and mandolin had matching holes through them. It was ugly.
If you really want to save the top, you might try dampening the busted up area before you try to bend it back into shape.
This looks to be refinished so I'd guess that someone attacked it with a power sander of some shape and thinned it too much. I can't tell very well but there appears to be signs of less sanding around the base of the fingerboard which may give you some indication of how much was removed. If it's as thin as it appears on the pictures it's possible that the top doesn't resonate very well now anyway so replacing it may actually improve the sound.
This may be a HORRIBLE suggestion, but it may lead you to a good one, so I'll post it.
I just dealt with a Venezuelan Cuatro with insanely thin sides and top. The wood all over was the thickness of veneer - about the same thickness as the wings of a balsa wood airplane toy, and about as strong.
I patched the cracks as best I could, but still have a pretty big hole with missing wood on the side. There was no way to pull the side off without destroying the wood, so I ended up laminating over it.
My first attempt was a piece of pine veneer that I had bent on a pipe. It fit well, but refused to clamp flat - the amount of pressure that was required would, once again, have collapsed the instrument.
I pulled that off, and then did the most unconscionable thing possible - I laminated over the hole with a 2 inch wide piece of heat-adhesive laminate. It is now solid, and while it doesn't look great, it seems to function just fine.
You might consider making a veneer for the interior of the instrument, very thin, but enough to give strength to the top. You would be putting in all kinds of patches anyways, so you might as well just veneer the whole thing. I don't think that you need to use the heat-adhesive for this, since you can probably clamp it just fine. Then you can cut through the soundholes and shape them to look correct again.
You know, Mark, that might not be a bad idea at all. It would save the original top and it probably wouldn't be any more work than making a new one from scratch. I'm not so sure about the longevity of the heat activated glue you used but you can be the test subject on that too.
Ugh, tell me about it. Luckily, it's for the side of the instrument in my case, not the top. Good 'ol hide glue for that. Or is it good ol' hide glue? Where does that apostrophe go, anyway?
Hit it with some steam, held my breath and pushed out from the rear. Everything popped back into place. Will need some interior reenforcement because of the cross grain breakage. Have some very thing poplar to put in there. Think it will work out okay.