Epoxy components usually harden rather more progressively, though polyester components have a tendency to harden swiftly, specially if plenty of catalyst is employed.[fifty one] The chemical reactions in the two cases are exothermic. Boat builders, surfboard makers and fabricators of every kind use epoxy each day to sort sturdy, waterproof, https://www.propanraya.com/id/produk/epoxy-fast-dry