EpoxAcast 690 Clear Casting Epoxy Resin - Trial Unit EpoxAcast 690 is a clear casting epoxy resin suitable for a variety of industrial and art-related projects requiring a rigid, clear finished casting; EpoxAcast 690 features a very low viscosity for easy mixing and minimal bubble entrapment; Working time is 5 hours and cure time is 24 hours at room temperature; Castings cure with negligible shrinkage and are very hard and strong. Resin can be colored with UVO or IGNITE colorants; This product is not moisture sensitive and can be used in humid environments. Recommended casting thickness maximum per layer is 3/8 in. / 0.95 cm.