If you’re waiting for your epoxy resin to cure, there are a few things you need to know. The cure time of epoxy resin depends on two things: the hardener and the temperature. AeroMarine’s 300 epoxy resin with 21 hardener has a cure time of about 24 hours at 70 degrees Fahrenheit, while our 5 minute epoxy has a cure time of about 60 minutes at 70 degrees. However, for every 10 degrees above 70 degrees Fahrenheit, the cure time is cut by 10 percent. Just make sure you don’t raise the temperature over 100 degrees Fahrenheit, or the resin might not cure properly.