Re: [CAD_CAM_EDM_DRO] Epoxy

Bill;

I buy large quantities of epoxy for various projects. www.raka.com has good
epoxy and their prices are half of what others charge. I just purchased
another 30 gallons from them this morning. I think they have a trial kit
for those wanting to experiment.

In general, the higher the ratio between resin and hardener, the better the
physical properties. However, high ratio epoxies are also more sensitive to
proper mix ratio and much more likely to cause skin problems. I stick to
2:1 formulations for this reason. West System epoxy is 5:1 and is known for
its ability to cause skin sensitization. It is also $75 a gallon vs $35 for
Raka 2:1 epoxy. Both are 100% solids amine cured resins.

Nearly any colored powder will work as a colorant. Just remember to get the
resin/hardener mix ratio exact. Unlike polyester, epoxy does not cure
faster if more hardener is added. Incorrect ratios result in incomplete
cure.

Use a slow hardener if you want to avoid bubbles. Going over the surface of
the applied epoxy lightly with a heat gun or propane torch will pop most of
those that form. Vacuum bagging also works but it can be a pain to set up.

Epoxy is habit forming. I started out buying three gallon kits. Now I'm
strung out on truckload deliveries. Read some of the testimonials on the
West System website and you will see why.

Doug