Hi all!

Putting together a Vector Flight 66" Extra. The forward fuse area is huge when compared to the 40 sized planes I'm used too. The fuel tank compartment is not fuel proofed but I don't want to mix up the large volume of thinned epoxy that I would need to cover all of that balsa. Is there any sort of paint that I can buy that can be used for this purpose?

you can buy any email paint, car paint in spray or graupner offers a goon paint named Alkyfix - the best I´ve try

My fravrite is AeroGloss by Midwest...... You'll be able to find a huge assortment of different brands and colors of Fuel proof or "dope" type paints at most good Hobby Stores. Just make sure it says "Hot Fuel Proof" or "dope" .... I'd say it's by far the lightest weight method to fuel proof since most the weight evaporates!

I have found the best to be fiberglass resin. Hardware stores carry these and they come with a small tube of liquid hardner. The viscosity is just like oil, so it can be applied in every nook and corner with a brush, it penetrates the balsa and strrengthens it also and makes it tremendously fuel proof. Look out for drips as it takes about half hour to become tack and drip free. But if you apply thin coats it will not run.

Clear Polyureathane works great. Look on the shelf at the hardware store. It comes either as a liquid or in a spray can. For extremely hard to reach areas you can shoot the spray into a straw or if using the liquid type of can, pour some into the area and let it flow around. There are several brands. Mini Wax is one.

BTW polyurethane is the same base that is used for some brands of matching colored sprays for monocote or ultracote.

Ernie

What is wrong with thined epoxy?

Dave,
Thinned epoxy is the most chemical or fuel resistant coating , followed by solvent based polyureyhane and then clear butyrate dope. Although butyrate dope is touted to be fuel proof, raw soaking glo fuel will damage and remove it. Stay away from any water based coatings.
The easiest way to go is clear Min Wax solvent or oil based polyurethane. Comes in small half pint cans at most paint or hardware stores.
I prefere epoxy thinned with denatured alcohol but the preparation does require a little more work.
BTW if your tank and tubing is leak checked prior to installation there is no need to fuel proof the entire tank compartment. Just everything forward of the firewall and maybe the back of the firewall.

That last sentence should have been, " Just the firewall , front and back, and eveything forward of the firewall.

Exhaustive leak check it is then!

Leaks can be unexpected and happen later on, after the initial leak test. Fuelproofing the whole compartment might not be a bad idea at all.

Now, how to test for a leak? Putting the tank underwater and blowing into one of the lines seems to work (so far...) for me.

Ernie

SOLARFILM "CLEARCOTE" is designed just for this.

Just paint it on with an old, or cheap, paint brush. It drys in a couple of hours, but needs 48 hours to cure.

Don't do it in the house though, or the wife will have you living out with the dog real quick.

I have used brushed on (usually black) Rustoleum in the engine bay with good results. It is fairly cheap.

How 'bout "epoxy" appliance paint in spray cans??

Allen

Thinned epoxy! Not that hard and do it all the way back to the rear of the radio compartment. If your tank splits in a year from now you'll be glad you took a little extra time to do it right. Use an acid brush and bend it 90 degress for the hard to reach places.

Pick up disposable mixing cups and denatured alchohol and popsicle sticks and do the job right. If something comes apart months from now you'll really kick yourself for not doing it right the first time.

Yeah, sigh...no short-cutting this one I guess...