Notes on Using Epoxy Resins for High Power Rocketry

Optional

We like to have a two-part epoxy putty on hand for use as weight in nosecones or for any random epoxy need where the more liquid variety might drip away. These are usually found with the other glues and epoxies. They have a thin plastic separating the two parts, which require a certain amount of kneading to mix to the correct color and enable the curing process to start.

One Way Rocketry does everything that might help make a launch more reliable, or more simple. To that end, we leave little to chance. Putting a weight in a nosecone, even one made from a two-part epoxy itself, might still break loose on a really high acceleration launch. That’s why we always backfill the nosecone with an expanding, heat-resistant, two-part Adjustable Density Expanding Foam from Public Missiles LTD. We also like to fill the gap between the airframe and the motor tube with this expanding foam. It usually helps brace the fins that are fitted through the airframe. While optional, it is highly recommended. The foam set from Public Missiles will last a while.

Who hasn’t used cyanoacrylate, a.k.a. “Super Glue”? Its great to have on hand for a variety of uses, but is not required for High Power Rocketry. We sometimes use it as a very quick-dry “tack weld” to hold something perfectly in place until we get the epoxy to set.

Cleanup

An ounce of prevention is worth four half-pounds of cure; one part each resin and hardener.

Abraham Franklin

The best cleanup for epoxy of any kind is to plan ahead and leave nothing unwanted behind; or at least leave behind only enough to wipe up with a paper towel. Having said that, Acetone is the best answer to uncured epoxy cleanup. We buy acetone by the gallon, and refill an Acetone Resistant Trigger Sprayer from Delta Industries.

Acetone also works as a thinner for the epoxy, and may slow or stop the hardening process, depending on the amount. We don’t recommend “thinning” with any more than 10% of the mixed epoxy volume. So if you were to make 200mL mixed epoxy, try not to exceed 20mL acetone for thinning.

Paper towels are your friend. Speaking of friends; keep your friends and family happy and buy separate rolls of paper towels just for epoxy work. Don’t be afraid to use them, and its always best to first wipe any uncured epoxy from your skin with just paper towel to physically remove the resins and solvents. Soap and water may not remove epoxy from your skin. Best is to wear disposable gloves.