fuel proofing paint
 

Sprayed my plane with krylon red and yellow paint last year. The good news is the plane flys beautifully.... but the bad news is..... my paint job is not fuel proof. The plane's been sitting all winter and the paint is very dry by now. I bought Dupli-color clear car lacquer (see photo below) and was going to spray over the colors on the plane to hopefully make it fuel proof. May understanding is you can put lacquer over krylon... but not the other way around. Do you think the lacquer will fuel proof the plane. planning on putting several coats of lacquer. Any help will be appreciated.
Dick

RE: fuel proofing paint
 

I really like the selection and ease of Krylon and Rustoleum in the rattle cans too, unfortunatly I've run into the same problems as you as well.

Bad news,
After reading dozens and dozens of posts on paint over the past several years it is my understanding(and further experience) that there aren't any off the shelf, readily available, paints that will stand up to nitro. There were several people who said that they had good results with various rattle can colors and clears, including krylon, varathane, polycrylic spray, rustoleum and dupli-color...My personal experience, after reading these post and doing test panels, is that none of them hold up to raw or hot fuel.
The only 1 part, ready to spray, product off the shelf that has been any good is lusterkote clear, (except that over krylon O.D. green it wicked up the color over 2 years and turned black in several spots making the rear top fuselage on a desert camo ME109 turn all one color...black[:o]). Any relative humidity over 60% makes it milky to varying degrees as well, especially the flat. For me, several light mist coats and later, a heavier coat, has worked well over all of the Home Depot, Lowe's and auto parts store paints with out crazing or orange peeling. Others have had disasterous results over enamel.

Good news,
Some auto paint stores will mix either or both catalyzed(2part) enamels or catalyzed laquers in clear or color and put them in a rattle type spray can for you. This route has a very limited shelf life, as in 24-48 hrs max, once mixed in the can. If you are able to spray your own, you can get the paint and the catalyst seperately and mix/spray your own. This has also worked well for me in the past (both ways).
By far, I am really happiest with both the Nelson's Hobby catalyzed clears and the KlassKote clear 2 part spray epoxy. Both are pretty easy to work with if you have any spraygun experience at all. The nelson's does fairly well when brushed on as well, and is water clean-up . Haven't tried the KlassKote brushed yet, but it does spray nicely. Higher humidity hasn't been an issue when spraying yet for either one, which is good for me. We don't get a lot of warm, low humidity days in NC.;)

http://www.klasskote.com/

http://www.nelsonhobby.com/paint.html

good luck!

RE: fuel proofing paint
 

The Klass Kote clear brushes on very well too. The price is a big problem though but it mixes 50/50 then you can thin it down another 50 so it goes a long way. I just buy the cheap HVLP spray guns at Harbor Freight when they are on sale, they work very well. One thing I worry about is the fact that the plane has been flown so there is probably oil on the plane. It has to be very clean before you put anything else over the paint.

RE: fuel proofing paint
 

I am interested in the laquer clear coating and how the paint underneath would do. Laquer clear and stain can be purchased at the hardware off the shelf. I have used Minwax Polyurethane over latex and over the iron on fabric coverings and it does very well standing up to 15% nitro and to gas. The problem is that it will yellow and shows on all of the lighter colors.

Let us know how the laquer works out for you, I for one am very interested. It works for the auto industry, or used to should I say. I think those were all catalized though.

Inquiring minds want to know!

RE: fuel proofing paint
 

What does it cost to have auto paint put in a can?

RE: fuel proofing paint
 

I've heard that Krylon paints have been reformulated so they don't stand up to gasoiline as well as in the past. I'm not sure if they were ever up to nitro. Our local auto body supply houses carry a two part clear in a rattle can-once mixed it must be used within 24 hours. Costs about $18. They also sell a wide array of 2 part clears. A quart of clear and a 1/4 qt. hardener go for about $40. Problem is, they say I shouldn't spray it over latex paint. Trial and error, very time consuming and expensive. I've tried Nelson's clear, and while it looks pretty good and is easy to clean up, it's expensive, it's a pain to brush on and I can't get a good spray out of it. I'm pretty sure it has something to do with the very low humidity here in Utah. I haven't tried KlassKote yet, but that may be my next stop.

RE: fuel proofing paint
 

In rattle cans, your bet bet is an acrylic.

You results will range from barely fuel resistant to almost fuel proof.

Do a test panel, and when dry, hold it about 10" away from the exhaust of a running engine for a tank of fuel (wear gloves for this). Let it sit overnite, then clean it off. You will have your answer as to whether it is fuel proof or not.

As for using the lacquer clear over enamel - I have found it safer to use the same type of clearcoat as the paint - enamel paint, enamel clear coat.

RE: fuel proofing paint
 

Yep, enamel over enamel and lacquer over lacquer!! I have messed up more then one good paint job trying to mix and match paints and primers. I have a chart hanging in my shop now that shows me what different brands are because sometimes it isn't on the label. Or I could have just missed it???:eek: It happens!!

RE: fuel proofing paint
 

I have had very good luck using OIL BASE Polyurethane in the spray can, and yes it will yellow if used over white or light pastel colors. Yellow and red are my two favorite colors on my planes so the yellowing is not a problem as there is none that shows over those two colors.

RE: fuel proofing paint
 

Your best bet for a fuel prof paint is an automotive type catalyzed polyurethane. You can get it in qt's with a 8oz can of catalyst. If you buy Dupont, PPG or BASF, you can get a 4 to 1 mixed clear that will keep for years. Its your best bet, FAR better than ANYTHING you can get a hardware store.

<span class="mContent">Lacquer-based = not solvent resistant </span>
Enamel = a little stronger, not much more
Acrylic Enamel = catalyzed enamel, the 1st level that offers any resistance to fuel
Acrylic <span class="mContent">Urethane</span> = much stronger than Acrylic Enamel
Acrylic Polyurethane = super strong, very resistant to fuel
Apoxy = like concrete, laughs in the face of fuel

RE: fuel proofing paint
 

Where I live it almost never gets below 60% humidity so using Lustrekote clear's always challenging for me. I've had good success removing the fog from this clear by waiting till it's fully cured and hitting it with automotive polish - this takes a very thin layer off the top of the clear and that's where the fog usually is. Just don't go nuts with the polish or you'll take off all the clear!

RE: fuel proofing paint
 

Have you thinned the Nelson's? Even on low humidity days (few and far between in NC) It seems to spread well using a foam type brush/applicator. Lays out well, dries quickly at 2/3-3/4 clear & 1/3-1/4 reducer(water). Sprays well at that mix too. Denatured alchohol works as a good reducer for spraying since alot of it evaporates as the paint is coming out of the sprayer, lets you put down a heavier coat without runs because the paint that hits the surface is thicker(less runny).

KlassKote is great...have plastic and alum spinners painted with it and they stand up very well to the electric starter. excellent clear coat, brushed or sprayed. tedious to clean the sprayer so I usually just do whole planes in clear then toss the gun. If you have a harbor freight locally you can pick up a detail sprayer for about $10.00on sale fairly often.

http://www.harborfreight.com/cpi/cta...?itemnumber=86

RE: fuel proofing paint
 

During the summer here high humidity gets to be a pain as well, in the winter it can get pretty low and doesn't increase in the shop when I crank up the heat.

The fogging is really just water condensing on the surface of the paint as it cools during the drying process for enamels, laquers, etc. it leaves micro pits in the surface of the paint and that's what causes the "fog"...You're right it is pretty easy to buff out and easier to go too far :) I've had good results with brushed on epoxy paint (KlassKote) when the humidity is high. Probably since it heats up a bit as it cures so it doesn't cause the same condensation effect. Sprayed, it can pick up moisture between the spray nozzle and the sprayed surface sometimesand that can cause a bit of a haze too. Harder to buff that out too, 'cause it seems to be throughout the entire depth of the finish:eek: