need help with painting cowl

[Flyguy172]

I need help with painting my cowl. I have both enamel and acrylic. Do I need to paint the inside of the cowl as well as the outside? Would I need to “rough up” the plastic so the acrylic paint can stick? Could the enamel deform the cowl? I am building to fly so it needs to be light but I still want it to look good.
Thank you in advance.

[fychan]

I have painted the inside of my cowling a dark brown (nearly black) - but the reason for that is solely that because it has a 049 engine in it, I've had to cut large holes through it for the prop, starter and piston heads to go through, so you could easily see the inside of the cowling around the engine.

As for roughing up - yes I made the mistake of not doing so for the inside of the cowling and it took me 4 coats just to get paint on it all, and to stop it "balling" up. A light sanding on the surface of the engine exhausts made the (same) paint adhere MUCH MUCH better - one coat was enough!

As for the enamel deforming the cowling, I doubt it - I painted Airfix 1:72 scale models for years with enamels, and they were always fine - no matter how thin the plastic parts. Careful with the enamel thinners / white spirit / adhesive tho, as they will cause you problems on the thin plastic. Enamels are also heavier than acrylics, so if you're going for a really light aircraft avoid them if possible.

[Xanadu]

I really like using the acrylics, and they are much lighter out of the 2. They have no smell really, clean up with water, and very user freindly.

I have never roughned up my plastics so far, and had no troubles with the paints sticking.
The color used will be the dictating factor I have found as per how many coats to put on.
Red so far has been the worse one for needing additional coats.
I never painted the insides, but I guess it would not hurt. Use a dark color for darks, light for lights.

[fychan]

Actually, I should mention that because I wsan't worried about the finish of the painted areas (they would be on the inside, after all), I used a very thinned down paint - about the consistency of milk. Could be a large factor in why my paint was balling

[Flyguy172]

Thank you for all of your help. I'm most likely going to use acrylics. Because I will probably have to put weight in the nose to balance the plane, weight is not as big as a concern as I first though. So I am going to paint the inside of the cowl first, and then paint the outside with more detail. I just found some scrap plastic from behind my desk so I’ll practice on that. The colors for the cowl will be, White, Black, a little Yellow, and even less Silver. And again, thanks for all the help .

[Xanadu]

I will have to try that........

[scigs30]

Use one coat of primer first, then paint the color you want. Just use the same brand of primer and paint so there are no problems.