I now know why everyone who has made a waterbox like this says that you couldn't make and sell them profitably. But it came together ok.
I just have to decide if I want to make a baffle or run it wide opened inside just like the superfreak box that I based this on. Then make sure the halves are clocked for optimal hose alignment and glue the halves together.
Yep the original superfreak carbon box that I have is wide open inside, if you hold it up at the right angle you can look right through it. I made this one from fiberglass scraps that were laying around as a test, but I will probably end up running it for a while. It is a lot stronger than I would have thought. I broke the pvc mold trying to get the halves to slide off it. I had the whole unit clamped in a vise and was twisting the waterbox off with a strap wrench. The side of the mold that was in the vise with the waterbox over it held up, but when I clamped the bare side of the mold in the vise it cracked before the other side of the waterbox released. By then I was long past the point where I thought the waterbox was coming off in 1 piece.
After wrenching the box around trying to get the mold out of it I would be very curious to see what it would take to get it to blow out. I would bet that I could pour at least a couple ounces of gas in, hit it with an air hose, and then ignite it and the box would hold up. I`m sure its not as strong as my Tem built carbon version, but those aren`t exactly easy to find. I have only seen 2 go up for sale and I bought one of them, should have bought the 2nd even though I didn`t need it at the time.