Epoxy Thinning

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If you're referring to the Devcon Two-ton, I've successfully used a small amount of denatured alcohol to thin it. It does make for a longer cure time, but it spreads easier and flows better. Thin it enough and you can even use a paint brush on it. BTW, the denatured alcohol works well for cleanup of your brush, as well as any excess spills!

an alternate is to place each part in a separate plastic cup(epoxy a weight on the bottom of each cup such that it will not float in the water bath.... ....take a pan thats at least 2-4" deep and gill with boiling water..way till the temp gets down to approx 120F place the 2 cups in this hot water bath ..apply just enough heat to keep the water bath at 120 F... when ready to mix do so....this will increas eth viscosity(the thinness) of the epoxy without weakening the epoxy. IT will result in the epoxy setting up much faster...so if its a 30 min epoxy it will probbay set in 15min or even faster...,etc...
Remember also that when you thin epoxy you will lose strength. But you will gain the ability to penetrate pores in wood. The West System product manual has an article on it.

The Devcon is going top cost you so much more in the long run. Get your epoxies from hobby stores like Hobby Lobby, Micheals, or any Nobby Stores that sell RC outfits. These stores will have your 5-min, 15-min epoxies etc. The thinnest I have used is Bob Smith 20-min finishing epoxy, as it nearly flows like water. The next up might be 30-min, allthough there is a 2-hour epoxy, but I am not sure if it is thin or not as I have never used it.

Should you try the 20-min for instance, and deem it to be too thin, you can in turn thicken it with a product called micro-balloons.

I typically use 5-min epoxy for surface mount fins only, 20-min for laminating composite materials (i.e. fiberglass; kevlar) onto bodytubesn and 30-min epoxy for fillets, and main bonding of structural parts.

The mid sized set of these epoxies cost about $8 and will build many many rockets.

Remember, more epoxy only adds weight, not strength...use only what you need and let the epoxy do the rest.

my $.02 worth...