I'm rebuilding an old French bass that was busted to splinters in a car accident. I removed some large breast patches from the top to find, to my horror...EPOXY! Those things were glued in sloppily with epoxy which was, in some places, thicker than the patch. The only thing that worked for removal was steel scrapers sharpened with a death burr. I spent hours getting this crap out. And the stuff had soaked into the top layer of spruce, rendering it stiff and no longer porous, so there was no alternative but to dig out some of the original wood. I think this was done during a period of lack of respect for basses, and I hope this type of work is not going on any longer...
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