hi , just looking to put my mind at rest . next summer im going to be building a 600 gallon tank for freshwater stingrays out of plywood and fiberglass and after talking to a fiberglass company about finishing the inside of the tank in a black gelcoat type topcoat he said i would have to heat the finished topcoat up with large hotair blowers / fan heaters to burn the styrene out of the topcoat to make it fish safe or drinking water safe . for some reason this is bothering me and i was just wondering if anybody else had any experience with topcoat/gel coat or have burnt out styrene themselves. thanks
fiberglass/topcoat question
- Thread starter fly boy
- Start date
I've never heard that before. As long as the surface is cured completely not still sticky to touch when you fill it with water.
This mite be of some help[, i was going to expalin but this is easyer LOL.
http://www.cfsnet.co.uk/acatalog/ponds.html
If you look through to the gel/top coat section it will explain. If its good for KOI then we should be fine, its what i am going to do with my 500g tank.
wayne
http://www.cfsnet.co.uk/acatalog/ponds.html
If you look through to the gel/top coat section it will explain. If its good for KOI then we should be fine, its what i am going to do with my 500g tank.
wayne
My 600gal tank is fiberglass with a gelcoat topcoat. I laid chopped strand matting by hand and sprayed pigmented gelcoat over top. I would definitely recommend doing every inch of the tank with cloth or mat instead of just applying resin/gelcoat directly to the plywood.
What the guy may be talking about is if you use "unwaxed" resin with your fiberglass, it will remain tacky, even when cured. This is because the moisture in the atmosphere prevents the surface of the fiberglass from properly curing. Even using "waxed" gelcoat, sometimes the surface stays tacky. The proper way to deal with this is to spray or brush something called PVA (a water soluble mold release agent) over top of the cured fiberglass. This forms an airtight skin on the fiberglass and lets it cure. The PVA can then be washed off. PVA is cheap at any plastic or boat repair shop, I think a gallon of it is $20 or so. You shouldn't need anywhere near that much though.
Blowing hot air onto fiberglass to "burn" the styrene out is nonsense. The only thing it might do is force the surface to cure due to the low moisture content of the warm air - but I wouldn't rely on that methot. Like I said, PVA is cheap and easy to use.
What the guy may be talking about is if you use "unwaxed" resin with your fiberglass, it will remain tacky, even when cured. This is because the moisture in the atmosphere prevents the surface of the fiberglass from properly curing. Even using "waxed" gelcoat, sometimes the surface stays tacky. The proper way to deal with this is to spray or brush something called PVA (a water soluble mold release agent) over top of the cured fiberglass. This forms an airtight skin on the fiberglass and lets it cure. The PVA can then be washed off. PVA is cheap at any plastic or boat repair shop, I think a gallon of it is $20 or so. You shouldn't need anywhere near that much though.
Blowing hot air onto fiberglass to "burn" the styrene out is nonsense. The only thing it might do is force the surface to cure due to the low moisture content of the warm air - but I wouldn't rely on that methot. Like I said, PVA is cheap and easy to use.