Additives

These hollow, purple-brown phenolic spheres make a low-cost low-density filler. They make a light-weight fairing compound with good compressive strength. Blend with Silica Thickner to prevent sagging. See this excellent primer by Christine Merchant

for making structural fillets Wood flour is very fine, filtered, sawdust-like wood by-product. It is an excellent all around filler for creating glues and structural fillets. Use in sewn-seam and stitch and glue construction. Wood flour combines with...

high strength thickening agent for epoxy The most popular thickening agent for epoxy, silica makes a smooth, non-sagging, high-strength mixture for structural bonding, filleting and filling. Mix both epoxy resin and hardener then add silica until the...

Glass bubbles are lightweight hollow white glass spheres. When mixed with epoxy, this light weight filler will make a very easily sanded putty for filling and fairing. Use the same as phenolic microballons.

Everyone knows it is dangerous to have slick surfaces on a boat. And everyone seems to have a formula for making a non-skid surface. You have heard of using such household materials as salt or sugar and you have seen exotic materials that cost an arm and...