"RG" wrote...
I need to add 3 coats of cloth to re-enforce the hull of my boat. I seem to
remember that one should NOT wait 24 hours between each application, or one
would have to sand/grind the surface to wax??? Is that correct, and what is
the best time to lay the second and third coats?

Read the literature from the epoxy mfgr to be sure; there will be differences
among them.

My experience is with System 3. Using their regular laminating epoxy, their
Epoxy Book says you can wait up to 72 hours without sanding, but I wouldn't wait
that long, especially in a warm environment. I generally waited 12-24 hours
(overnight or the same time next day), based on the convenience to my schedule.
That allowed the epoxy to cure enough that I could easily feather or trim the
edges with a Surform or razor knife as needed, and the surface was not so tacky
as to make positioning of the next layer of cloth more difficult.