I use Rustoleum spray paint on my DTFB models but there is no adhesion to the taped parts. The paint can be pealed off like a separate layer of plastic. Has anyone found a solution that will not damage the foam board parts?
I wouldn't use the paper tape as a hinge tape. It might work, but any treatment soaks in and the tape becomes brittle -- fine for an edge, but not so good for a hinge.
Have you tried sanding the packing tape lightly with a fine-grain sandpaper? it breaks the smooth surface and gives the paint more to grab onto.
You might also consider one of the paints designed for plastics, although I've seen a few of those not live up to their advertised "works on plastic"
finally, if all else fails . . . try Blenderm. It's a medical tape that works great as a hinge tape, but it's also a bit more textured. It's harder to find in brick-and-mortar stores, but it should have a better chance of holding the paint.
I use to fly JK Aerotech Mustangs, Zero's and Jugs in RCCA combat. Used Rustoleum over the tape by buffing it with 200 grit sandpaper. It did come off after a bit BUT that's because I was dousing it in 10-15% nitro. That and ramming them into other airplanes in search of streamer. Dry wings never rubbed off that I'm aware of AND thanks to the JK Aerotech style of building that soon took over,rarely did they wear out. I rolled over and pulled for a streamer about half too low once and planted my zero full speed into the ground. replaced a servo arm and made the next heat. Tough little buggers and with a screaming Norvel 25 they were doing uppers of 90mph. The little mustangs were just about untouchable. My Jug was pretty fast but it also had a ton of wing and would hang out in the tall weeds devilously. "Come on down and play" I'd yell with the only full streamer left knowing with a burst of throttle I could hop up the streamers of those that overshot and I could laugh at the folks that went under. I wasn't the greatest thing in combat mind ya but I didn't totally suck at it either.
Good old days.
More to the point, if you dull the shiny tape with sandpaper, the paint should stick for ya. Wouldn't sand a tape hinge.
All the FT planes use paper for the hinge so I'm not sure why paper tape wouldn't work there. You might want to tape both sides following the bevel so there is support and adhesion from both sides. Not sure about that surgical tape. May depend on the glue they use.
But I was more thinking of the wing joints and other structural places that tape is typically used in the FT designs.