I finished my 1/5 Sig Cub with 4 coats of nitrate dope followed by Rustoleum spray bomb (acrylic enamel), and topcoated with Minwax oil-base polyurethane. Portions of the plane (underside of wings, fuse, and tail) were done with nitrate dope followed by Top Flite LustreKote (acrylic lacquer) which also got a topcoat of oil-base poly. After 2-1/2 years, the finish is just like new, except on the underside of the boot cowl where the exhaust mist has caused the oil-base poly to wear through in a couple of places. The LustreKote underneath it is perfect.

I recently played with a piece of Koverall I attached to a frame and stretched. I painted it with latex interior house paint; the first coat was applied to penetrate the fabric, the second coat filled the rest of the weave, and the third coatsmoothed the finish to the point you could barely see the fabric. I let it dry for two days, then pulled the fabric off the frame, wadded it up, and then smooothed it out. The paint did not crack at all. I plan to cover my BUSA Bristol with Koverall and finish it this way, and then clearcoat it with LustreKote to fuelproof it.

Be aware thet oil-base polturethane is more resistant to glow fuel than water-base; oil-base will "yellow" the finish somewhat, water-base does not. I have seen on many of the models in my club that long-term exposure to fuel will break down oil-base polyurethane in areas that receive a direct exhaust spray. As an example, one of the guys has the BUSA DR-1. The landing gear winglet finish came completely off in about a year and a half with a glow engine, and the exhaust ended about 6 inches from the top of the winglet but was directed straight at it.