I'm about to make a plug for a piece that needs to fit snuggly over another piece. It's like the lid of a shoebox... at least, around the edges.
I need it to be pretty accurate (within about 1/8"). The piece is 24 x 15 inches.
How much shrinkage can I expect using polyester resin? I'd like to know how much to oversize the plug so the final piece will fit decently after the mold and part shrinkage.
Thanks.