I've got to tell you Ed, I don't know where you get your polyester
resin, or what was done to it, or what ever, but i've NEVER heard
of all this shrinking and twisting you're talking about. A mold needs to be reinforced to some degree, depending on the size of
the part. Thats where all the time and money is spent. But this
shrinkage? I've seen literally thousands of boats, boat parts,
and pieces of whatever come out/off molds, and NEVER have I
seen shrinkage. You better not let that secret get out to the
boating AND full scale aircraft world, or there will be some REAL
unhappy folks, finding out their investment is "Faulty".
Over 40 years in glassing, Steve