Sorry--I should have mentioned safety. Grinding/sanding fiberglass is not the healthiest activity. If you do much of it buy a decent respirator, not just a $2 dust mask (you only have two lungs). Wear googles or at least glasses. Wear old clothes and shoes. Keep your arms covered and wear gloves if you can. Wear a do-rag on your head. Don't grind/sand in a garage or basement. Don't wear your grinding/sanding clothes into the house or wash them with other clothing. When you're done for the day strip off outside and wash your hands, arms, and face in cold water first--ground fiberglass is ground glass. You want it off your skin. Cold water keeps your pores closed. Polyester and vinylester smell terrible (because of the styrene) and the odor is a clue that the fumes are not healthy. Many people think that epoxy is safer than polyester because it has less (almost no) odor. THIS IS NOT TRUE. In fact, epoxy is more harmful than polyester. Epoxy is chemically active much longer than polyester (days or even weeks), and epoxy is much more sensitizing than polyester. EVERYONE working regularly with epoxy will eventually become sensitized to it and develop an allergic reaction to it. At the very least wear good quality nitrile gloves (if you are not allergic to nitrile!) and use barrier cream. NEVER bare hand polyester or epoxy resins--try not to let resin touch your skin anywhere. Never glass in a living area or in an area with poor ventilation. Don't smoke. Don't glass in a confined area with a source of ignition. Be very careful with leftover catalyzed resin--it can/will get *very* hot in a big hurry. It should be kept in a fireproof place until it's kicked and is stone cold. It's not worth trying to clean most brushes and containers used when laminating. Use paper cups (or plastic cups that won't dissolve in resin) and chip brushes, and throw them away when done. Only dispose of gloves, brushes, mixing cups, wipes, etc in a metal container in a fireproof place, and check the container to be sure nothing is hot. There's probably more... but have fun anyway!