Teardrops n Tiny Travel Trailers

Has anybody made thier own (or know how to make) fiberglass holding tanks?

RV builder I formerly worked for occasionally made them. I don't remember much detail but I think they only used them for black and grey water. I think they were made of mat glass and polyester resin over 1/8" luaun plywood (plywood on the outside). Sections were either made in wide U-shaped molds or as flat panels, then bolted together with some kind of seal--rubber gasket material or maybe high-grade caulking, I don't remember.

Best,
Tom

Sounds like a lot of work for something that will probably end up looking home made (not to be confused with hand made) and will probably end up leaking sooner or later. Thanks for the reply. I know in production they use a blow up mold sprayed with release, then layer on resin and glass and cover with a vacuum bag.

You could make real nice custom ones out of glass but it is a lot of work for just 1 or 2 tanks. By the time you where done they would probably end up costing more than if you bought the plastic ones.

It's pretty common to do it that way in sailboats so you can take advantage of the odd shapes along the hull. If you're going to use styrene resin, the INSIDE of the tank needs to be gelled because fiberglass isn't waterproof and the smell of a black or grey tank will get out.

Now most are done with epoxy because for all intents and purposes, epoxy is 100% waterproof and doesn't impart any flavour to your water once it's off-gassed. I mix the resin with about 5-10% less hardener than the ratio calls for and cure it under heat lamps. That's because the (unmixed) hardeners contain BPA. Once the reaction occurs from mixing, that threat is gone, so the slight surplus of resin insures there will be so uncured hardener...just in case.

Build your tanks however you'd like, fillet the inside corners and use some epoxy with 6 oz cloth. I've been thinking about a water tank as part of a tongue box shaped like a pirate's chest, lol.