Like C.M. I stick mainly with slate. I use a good quality two part epoxy and it seems to hold the slate well and doesn't create any deadness ( I use a toothpick to lay it on in a thin bead). When I use it for a glass soundboard I distress the glass at the glue point and so far I haven't had one turn loose (knock wood). I am used to using lacquer at the pipe organ building business where I work part time, so I use it on my calls. If you use lacquer be sparing and build it up in thin coats ( if you try to spray it too thick it will run like crazy). Use 0000 steel wool to buff between coats and use a tack cloth (available from your home store) to clean up residue before the next coat. On pot calls I apply a coat of paste wax after the finish cures. Every Builder has his favorites, some of the old school guys even have secret formulas. No matter what glue or finish you decide to use be real careful not to get any oils, waxes or finish on your friction surfaces. Hope you have good luck and a good time making your calls.
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