Black Paint Advice

[wirejock]

Not to throw a wrench in the works but isn't the Corvette body fiberglass? Maybe I'm missing something.

[JonJay]

Originally Posted by wirejock

Not to throw a wrench in the works but isn't the Corvette body fiberglass? Maybe I'm missing something.

Yes. Black was a very popular color.

[rleffler]

Originally Posted by wirejock

Not to throw a wrench in the works but isn't the Corvette body fiberglass? Maybe I'm missing something.

Yes, but it is also not room temperature cured either. It is the room temperature curing that is the issue with the epoxy resin softening.

[BobTurner]

When I was young I had a dark VW with black interior, and a summer job at Quonset Point NAS where the car was parked on the blacktop ramp. At 5 pm I could not enter the car, it was that hot. I had to open the doors and let it cool for a few minutes. I have never since bought a dark car.
I don't know the temperatures needed to compromise the cabin top strength in a -10. But for sure, if you park on a ramp on a warm sunny day, a black paint job will decrease the lifetime of your upholstry and avionics, and be (more) unpleasant for you and your passengers (unless you have external power air conditioning) when you get in.
So, assuming the epoxy is okay, you just need to decide if the cost and unpleasantness of the heat is worth the look.

[TimO]

I know this is talking cabin top in black, but this is a tidbit just regarding the color.

I have 2 friends with RV-10's with black on their leading edges of the wings. Mine are white. There is a very very significant difference in temperature between the 2 when they're sitting in the sun. One of the 2 guys has commented to me that when he parks on the ramp he has to leave a couple gallons of fuel out of the tanks because with the black it heats up so much that it'll dump a lot of fuel overboard if he fills it all the way up. Mine dumps a little when it's hot too, even being white, but black is a significantly hotter color. At least on the aluminum you have no worry about structural integrity, but as Bob mentions, the type of epoxy cure on the RV-10 cabin top may not be the best candidate for black paint, since it's a structural top.

[Kyle Boatright]

Several issues have been raised. Another one is that a black cabin top is going to get hotter and expand through thermal expansion more than a white top. There have been many reports of cracks around the cabin windows. The thought is those are due to the different thermal expansion coefficients of the materials involved. I think black paint will make that problem worse, not better.

That said, there are plenty of dark (blue, burgundy) cabin tops out there. I wonder how they are doing with regard to cracks around the windows??

[Mel]

Originally Posted by wirejock

Not to throw a wrench in the works but isn't the Corvette body fiberglass? Maybe I'm missing something.

The Corvette body is actually FRP, Fiberglass Reinforced Plastic.

[bruceflys]

Tech support at Vans should be able to advise on the thermal consequences, or lack of same, of black paint on the cabin top's structural integrity.

[Carl Froehlich]

Originally Posted by Kyle Boatright

SNIP
There have been many reports of cracks around the cabin windows. The thought is those are due to the different thermal expansion coefficients of the materials involved. SNIP

I've seen several RV-10s with window frame cracks. While I'd assume a dark color would aggravate this issue, I offer the root cause is not properly finishing the glass to cabin top joint. On my plane I first took some micro and filled/smoothed the joint. After sanding, I put down a couple of bids of fiberglass over the joint. The fiberglass does not extend over the glass beyond the cabin top frame that the glass is glued to. That was followed by the normal micro-sand-micro-sand routine. I'm happy with the results. 500 hours over five years and no cracks.

Carl

[rvbuilder2002]

The RV-10 cabin top is vacuum bagged / oven cured prepreg. fiberglass (some of the discussion seemed to be implying it was room temp cure epoxy).

This would have a better tolerance of the temps that would be induced by a black finish coat when compared to room temp cure, but I have no data to provide that would convince me to say go ahead....

If you would like to do your own research contact Mike Daniels at M&W Fiberglass. Ask him what the material is that they use and then research tolerance of long term exposure to temps that can occur with black paint (more research).