We are vaccum forming wings and fuselages and are looking for something compatable with the epoxy to color it so there is no need for paint. Any suggestions?

I don't know how it would work with vaccum forming and I would suggest trying someting else first. ---- I have mixed food coloring in my epoxy to tint it, never tried for full color. I would also think " RIT " dye could work. The dye might change the cure time a little but should work.
If you try either one , let us know how it works. ENJOY !!! RED

What colors?

Skypilot One
I guess we don't want to limit the color possibilites. Just looking for what will work.
red head
Good ideas, will try them.

Your best bet is to spray color epoxy paint in the mould. Or you could add aluminum or other pigment recommended by the manufacturer.