Good fuel proofer?

[Doc J]

Hi Lads - I am taking a break from designing gliders and I'm doing a control line F2b stunt model - of my own design needless to say.

Thing is I have been away fro it for so long I'm out of touch.

Soooo...can any of you more knowledgeable chaps point me ago a good clear coat fuel proofer? I'll be using 10% nitro so it needs to be a good one.

Any help grateful received!

Couple of pics of the drawings etc below.

Cheers and thanks - Doc J.

 

[Konrad]

I've found that only catalized epoxy really is fuel proof, like to 65%. There are other finished that hold up fine up to 15% nitro. 2-stage urethanes like DuPont Nason works great, so does Klass Kote but a bit $$$. Non- catalized Urethanes are poor and leave a yellow tint.

If starting from scratch the classic butyrate dope over a few layers of nitrate dope should hold up fine against 10% nitro. I think Butyrate dope will hold up to 25% nitro. But it needs the teeths of nitrate dope underneath. I wouldn't use any of the dopes as a clear coat.

If clear coating don't forget to draw panel lines, real old school!

 

[kenh3497]

I've found the automotive urethane paint to be "more than enough " fuel proof unless you run 30%+ nitro. I use house brand paint and have had no problems.

Ken

 

[Hank]

I have used Minwax polyurethane spray from the can. The new version of spray does not yellow. I left it to cure for a couple of weeks before exposing to glow fuel. I have not flown the plane enough to determine long term wear. But so far after 8 flights no problem.

 

[joefly]

I use finishing epoxy mixed with 50% alcohol and brush it on. For firewalls, I first paint it with craft paint with a matching color and then finish it with the above mixture.