Hi, I'm completely new to epoxy resins but was looking to experiment with a smaller piece of timber before I tried something larger. SO I ordered a piece of waney edged timber on ebay, but the thickness was only 18mm. Will GlassCast 50 work here? Looking at the river table video, I was going to seal the under side, pour the river but then also use the same to do a top flood. Would this work?
Thanks.

18mm is fine.  GlassCast 50 when cast in wood (such as river tables) can be poured up to 25mm thick per layer, so you should be able to do that in one pour once you have sealed the timber and are good to go.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant