So I have a Windrider Hawker Hurricane, appears to be EPO, comes unpainted so you can choose your own scheme. Painted it up, flew it a couple times, let it get too far away, lost orientation and crashed it. Smashed up the nose pretty bad so got a new fuselage. First time around, wiped it down with denatured alcohol, then painted it with airbrushed latex house paint. Looked awesome, but even after many months, even low-tack masking tape pulls off the paint. I have been testing finishes using the inside of the old fuselage. Wiped it down with paint thinner, then denatured alcohol, then acetone. Tried Krylon Fusion. After a couple days of drying, paint came off with masking tape. Tried WBPU, ditto. Tried oil-based PU, ditto. Was hoping I could find something that stuck well as a base to paint over with latex, so far not encouraged by test results. Multiplex has a "primer" for Elapor/EPO--not a paint but a cleaner & solvent to prep surface for paint--that can't be shipped to the U.S., not sure why but it is extremely toxic and flammable. People talk about mold release, but to me the surface just feels super slick, almost greasy, even after solvent cleaning. I remember reading about some other foamies with similar paint resistance, I think the Flyzone Beaver was one.
Any suggestions to improve paint adhesion?
- - Dave

P.S. Oh, yeah, also tried Zinsser 123 Bullseye, had high hopes from other posts, but even after 3-4 days, still came up with low-tack tape.

Good quallity dyes make EPO surface very smooth - not very much for paint to grab.
For EPO you can rely only of mechanical paint stickning. And your parts are smooth and flexible - not good combo.
Answer to your problem is very simple. Help paint to have something to grab on. Before paint carefully sand EPO with 200-400 grit paper.

Try Rustoleum X2 for plastics. It worked great on a Fun Cub which is same material. Do a light coat and let dry for 2 days, then work up to full coverage. I only did 3 coats total on wing and it looks great and doesn't chip.

DaveA,

Many mold release agents need to be washed off first with warm, soapy water , and then move on to either denatured achohol, or automotive wax and grease remover. Next step would be to sand lightly with 600 grit paper. Next step is to use a aerosol automotive paint adhesion promoter such as Bull Dog, designed for plastics. Looks like rustoleum and Duplicor are making clear adhesion promoters as well. One or two LIGHT coats, let dry, and paint.....