I did the Hickory Valley log pond way back in about 1976 with clear casting paper weight resin, worked great. So I thought I knew what I was doing when I went to attack the Hickory Bridge T-trak module.
I did the entire thing with Michaels castin' craft resin, which is some of the stinkiest stuff imaginable as well as exothermic; the pour was 1/4 x 10 x 34 inches so that's a LOT of material.
What a disaster that was. First, it started to ripple... then it broke loose from the bottom and look 'silvered', well... I can live with that...then it shrank and split right at the bridge piers. I panicked and ripped the stuff out before it got worse as it was still warm and a little soft, in the process, ruined the carefully painted plaster bottom. Took several weeks to repair all the damage and redo it for another shot.
This time I used Deep Pour.... about 2 1/2 bottles worth to do the same depth, and that was now over two years ago. It worked GREAT. It hasn't warped, cracked or yellowed. A lot of people have now seen this at Altoona. So it's a hearty endorsement to say the least. Since then I used it on the creek on the Trunkeyville module, and I'll be using it again. It did what it was supposed to do and didn't stink up the place either.
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The creek at Trunkeyville had the water effects ripples added:
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I've got another log pond to do, and a creek, and I'll be using it again. I never want to risk total failure of a final scenic detail like I did on the bridge again. If that had hardened after it cracked I think I would have thrown the entire module out.