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I'm a newbie when it comes to fiberglass, so please leave comments!

**Correction: Minwax Polycrylic is actually acrylicbased, not a true polyurethane or urethane.

**42918 Updates:
After about 40 flights, both the epoxy and the Polycrylic fiberglasscovered areas on my DIY Specter V3 plane are sticking and strengthening well. The only downside I see is that neither covering stuck well to the lightweight spackle I used to fill imperfections.
Denatured alcohol does not dissolve XPS foam (extruded polystyrene). Several things will dissolve it, however (acetone, benzene, CA glue, etc), but not denatured alcohol. I think confusion about this is the source of some dislikes on this video, and that's fine.
*end of updates*

I'm building my first hotwire cut RC plane out of XPS foam (Owens Corning FOAMULAR 150) and comparing how well this foam covers with 3/4 ounce fiberglass using Minwax Polycrylic or ZPoxy brand epoxy finishing resin. I compare adhesion, puncture resistance, and rigidity. I find that both of these are useful adhesives with different strengths!

Thanks to NoddRC for making a similar video using DTFB:    • Nodd RC  039  Polycrylic  

And thanks to the AMA for this fiberglass and ZPoxy tutorial:    • Fiberglassing Tutorial with Greg Hahn...  . This is where I learned to mix the two Zpoxy parts together and split it with denatured alcohol.