TotalBoat ThickSet Epoxy can be applied directly over TotalBoat High Performance Epoxy before it has fully cured. The High Performance Epoxy has to react and go through the exothermic reaction before applying ThickSet. Once the High Performance Epoxy has passed its peak temperature and cools back down to a relatively warm room temperature (75-85°F), it can be overcoated with TotalBoat ThickSet. At this stage, the High Performance Epoxy should be firm, and may have a slight tackiness, but it will not be fully hardened.