"Filling the Weave"

Without epoxy, fiberglass is just an itchy, loosely-woven fabric that you can unravel in your fingers. Saturated and bonded to plywood in a hard matrix of marine epoxy, fiberglass cloth becomes a tough sheathing that is singularly strong and durable. The trick is to gauge how much epoxy to apply to the fiberglass. Too little, and you're missing out on the strength and abrasion resistance of the 'glass sheathing. Too much epoxy, and you're adding a lot of weight but no strength, and you're wasting epoxy.