Black Paint on fiberglass

[Andrew Anunson]

Originally Posted by wawrzynskivp

An A&P advised me that black paint will cause my fiberglass to go past its Tg and distort.

Composite aircraft parts are painted light colors so that the core material (most often foam) does not exceed temperature limitations (in addition to fiberglass and epoxy getting to hot). The foam core is the part that will melt from high heat.

What is the core material of your composite canopy? What is the temperature limitation of that material?

[bruceh]

My wing tips are black and I haven't had any issues with heat from the sun. Even in 100+F temps in the summertime.

[Captain_John]

All of my fiberglass is painted black.

CJ

[broken1234]

The key to making black (or any dark color) last on glass is filling the weave with something that won't shrink, and letting it cure... TIME is your friend... avoid polyester products...
Brad

[penguin]

Originally Posted by Andrew Anunson

Composite aircraft parts are painted light colors so that the core material (most often foam) does not exceed temperature limitations (in addition to fiberglass and epoxy getting to hot). The foam core is the part that will melt from high heat.

Sorry, this isn't true! The core material generally has much higher temperature limits than the epoxy resin. It very much depends on exactly which resin and which core material we are talking about, there is a wide variation in properties. I agree with Brad about avoid polyester - in fact the least filler the better!

Pete

[Brent]

I used black primer surfaces on the cowling. I had problems with blistering of the gel coat. From my experience I would recommend NOT using black. Having said that, I could perhaps just be unlucky with my particular cowling.

Brent Owen
RV9a
RV8 .... almost ready!

[thompsonbr87]

I wish I were more knowledgeable on the subject and could give you some advice, but I bought mine already flying. For what it's worth, though...

[vfrazier]

My RV-4 is black on top and on the leading edges. The fiberglass doesn't seem to care.

HOWEVER, it is shocking to see the leading edge ALUMINUM parts distort after a descent from cold altitude to a hot sunny ramp. I just about soiled myself the first time it happened. But as soon as the spar warmed up and grew to the same dims as the skins... gone.