For over 50 years, EA-40 epoxy has remained one of the most widely used laminating resins for making archery bows in the world.
The most common reason for crystallization in epoxy resins is temperature related. Our recommendation for storing all materials is at a constant 73°F / 23°C. However, sometimes EA-40 is exposed to cold temperatures or even freezes solid in transit.
This will result in the resin exhibiting crystallization (small particles) coming from the Part A on the wood surface and can even result in delamination between layers.
Remedy; some bow makers have been successful in eliminating crystallization by heating the Part A 150°F/60°C for 4 hours, thoroughly mixing every hour. Do not heat the Part A in plastic containers and don’t use your home ovens. We’ve had customers melt their containers in their home ovens. After heating, let cool to room temperature before using.
Another reason for crystallization is old material. If crystallization occurs due to the material being too old, eliminating the problem may not be possible. Too old is anything beyond 24 months from date of manufacture in an unopened container.