epiphiny43
Posts: 688
Joined: 10/20/2006 Status: offline
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Lucy's link is correct. (http://www.doityourself.com/stry/how-to-refinish-a-fiberglass-bathtub ) You want an activated carbon cartridge solvent safety mask. If it doesn't fit tight around your face and against your nose, it does little good. Using a spray gun without safety googles is retarded. A cheap paper set of sanding/spray overalls saves clothes and most toxic exposure. It Ain't that toxic! Friends are over 60 who haven't used masks and work with fiberglass and resin every day, since the 60s. We don't want to know what their liver looks like, however. You can use a brush if a cheap Harbor Freight spray gun and a source of compressed air isn't available. Expect to sand out brush marks with affordable brushes. I do this professionally with expensive brushes and would never guarantee the vertical walls to come out nice without re-sanding. If the tub can be rotated paint each surface when level/flat. Do the next as soon as it starts getting tacky and won't run. Your finish won't come out any better than your sanding job. 200/250 grit should be fine. Change sandpaper when it clogs and stops cutting well. NO swirls and gouges, use a soft backed random orbital sander attachment. Hand sand the corners where the power tool doesn't fit. You are through when all the shiny is scratched off, and the dirty coating is removed. Good light is essential. Take breaks if your back or other muscles involved in sanding start talking to you. They'll be louder later. ACETONE DOES NOT ATTACK FIBERGLASS OR ANY RESIN MATRIX IT'S USED WITH. Anyone who works with the materials knows better. Acetone is also a normal part of our internal metabolism, but in Smaller quantities! Don't freak if some splashes on you. Don't promote it either. The resin is worse, and no more toxic than any number of 'household products' under most kitchen and bathroom sinks. Half of these are likely to kill your pet birds, and are poisoning your children. And the Combover is annihilating the EPA . . . YOU don't have to be a retard, research what you put in your home's air, and on your skin. The various laminating and gel coating materials are potentially toxic. The resin catalyst is the worst (Methyl Ethyl Ketone Peroxide), handle Only with barrier gloves on! A good policy for all fiber laminating materials or coatings over them. I use a holding tool or wrap as the MEKP tends to run down the sides of the small squeeze bottles you buy and dispense it from. DROPS, not squirts, or the gel coat goes off in your gun before you are finished spraying. Find directions for the product. Read them. Follow them. Test your barrier gloves before working. Many dissolve in the common polyester resin, due to the styrene in the mix. Some won't tolerate acetone. I use the yellow kitchen gloves if a box of suitable disposable gloves aren't at hand, but some brands tend to leave yellow spots on work once the gloves have been exposed to solvents. Disposable mechanic's barrier gloves are cheap and if chemical resistant, my choice for their tear resistance. Dispose instead of clean with fresh solvent. An argument for cheap 'chip brushes' if not spraying from a gun. You NEED solvent to keep the spray gun working. Clean after each use before the gel coat hardens in the gun. If a coat needs more sanding from your learning curve, you have to let it cure to fairly hard, then scratch the whole surface if the next coat is to bond. This goes fast with clean paper and sanding at the earliest possible time. If the sand paper is clogging badly, you are too early. You want dry dust but easy cutting. Use firm blocks wrapped in paper to flatten off brush marks. STOP sanding when its flat, before you go through to the old surface. A side light helps greatly when sanding. Susceptibility to fiber glass particle itch is avoided in you only sand the existing gel coat, NOT sanding into the fiberglass. Even when into the glass fibers, some itch badly, others never notice. Washing off with cold water works better. Hot water opens all the skin pores and the smaller fiberglass bits don't get washed off. See above on paper barrier suits. Last one I bought was ~$5. Before sanding and refinishing, try various cleaners. 409, Boat hull cleaners (Expect to get raped by boat supply houses, it's their tradition.) Simple Green, Acetone. MEK if you know where to get it, and have access to a good mask. Stay UPWIND of all solvents in use. USE Gloves. (MEK is not MEKP, the polyester catalyst!)
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