Drill Bit / screw sizes

Thanks To All Who responded,
Thought for sure there was a fiberglass screw/drill bit chart. There should be one. Have seen to many people crack their fiberglass by forcing a screw. Appears that a 1/32 to 3/64 of an inch less than the thread diamater will be about the right size pilot hole. Always remember to put petroleum jelly on the screw threads.