Resin can cure either in the open air or in the presence of applied vacuum pressure using a method called vacuum bagging). Our Wet Layup guide focuses on the air-curing method.

An epoxy resin layup will cure in the presence of heat.

The cure rate of a polyester or vinyl ester resin layup can be accelerated by using a higher percentage of MEKP catalyst. Polyester and vinyl ester resin that does not contain wax, needs some other mechanism for effecting a cure, such as PVA (polyvinyl alcohol) or vacuum pressure.

Only the final layer in a polyester or vinyl ester laminate needs to contain the wax in order to cure; the build-up layers should not contain wax.

The vacuum bagging process involves placing the layed up piece (either a part or an entire hull) inside a plastic bag, applying layers of release and breather fabric atop the resin-saturated laminant layer(s), sealing the bag, and applying vacuum pressure until completely cured. The benefit of vacuum bagging is that it removes all excess resin and trapped air, resulting in a laminate that is lighter and has better strength.

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