Hi, I’ve been infusing a fairly complex part which is gelcoated - Double gelcoat, then laid up and infused using polyester, quite a thick layup of heavy cloth (6-7mm) and the resin keeps getting through onto the tool side of the gelcoat, and then deforming the gelcoat surface so that it takes ages to get flat again.. any tips?!

If the gelcoat is not fully cured it will likely move. Also the styrene in the infusion resin may well be softening the gelcoat making it worse. Also if the gel pre-releases, it will provide an easy path for the infusion resin to flow between the gel and tool surface. 

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant