EZ Kote vs EZ Dope vs PolyCrylic

[Ara Dedekian]

     Has anyone had any experience using water based EZ Kote or EZ Dope for fuel proofing? Their ads claim they are fuel proof. Minwax Polycrylic is not. I've got some really annoying gooey areas on my BiSlob and a FF Old Timer where I applied the Polycrylic behind the exhaust stream.

     EZ Kote is advertised as a water based replacement for epoxy and EZ Dope as a water based replacement for dope. My experience with polycrylic is leaving me a bit skeptical. I'm repairing an ancient foam combat ship for Brodak and want to slap some kind of coating over the foam as its life span may likely be under five minutes. I don't care about weight. All it needs to do is fly and turn slightly better than a Ringmaster. I want to save my SLC for a more deserving plane.

     Ara

[Paul Taylor]

Nothing is fuel proof it’s just some things are more fuel resistant than others. I would suggest slapping some rust-oleum on it. Let it gas off for two weeks should be good to go.

[bill bischoff]

Why not use Econokote or any of many other cheap low-temp films, and seal around the seams and edges with finishing epoxy? I have used low-temp film on a host of quick and dirty foamies. It lasts as long as the rest of the plane!

[dave siegler]

Polyurethane spar varnish has worked for me.  It yellows a little but it is fine. 

[Steve Dwyer]

Ara,

Another option if you want an easy application of a truly "fuel proof" coating is the KBS Diamond Clear. It's not water based but you can use it inside if you're concerned and not spraying an excessive amount. It's a two-part spray can application where you shake to activate. It has a surprisingly long shelf life once activated as well. The other option is separate 2K automotive finish. Photo is of the KBS is on the left and a 2 part on the right.

Steve

[Paul Taylor]

Ara,

Another option if you want an easy application of a truly "fuel proof" coating is the KBS Diamond Clear. It's not water based but you can use it inside if you're concerned and not spraying an excessive amount. It's a two-part spray can application where you shake to activate. It has a surprisingly long shelf life once activated as well. The other option is separate 2K automotive finish. Photo is of the KBS is on the left and a 2 part on the right.

Steve

If you let fuel set on any painted surface over time it will eat into the paint. It’s like a solvent. No matter how well we clean our planes fuel wicks into the wood.

[Steve Dwyer]

Paul,

I suspect if you flooded a "finished" surface with raw fuel over time it could probably damage/penetrate (??) any finish depending on the material. I'm, however, referring to raw fuel splashing onto a hardened catalyzed topcoat finish like the KBS Diamond product or an auto finish two-part urethane. In my experience there is no damage such as dulling, discoloring or lifting. Using these harder finishes provides much better or safer protection to a custom paint job. Even Acetone has little effect. I have seen many here refer to them as "fuel resistant or fuel proof." Of course, we can't leave out the added weight price we pay to have the better protection.

Steve

[Jim Svitko]

Ara,

Another option if you want an easy application of a truly "fuel proof" coating is the KBS Diamond Clear. It's not water based but you can use it inside if you're concerned and not spraying an excessive amount. It's a two-part spray can application where you shake to activate. It has a surprisingly long shelf life once activated as well. The other option is separate 2K automotive finish. Photo is of the KBS is on the left and a 2 part on the right.

Steve

The single-part KBS Diamond Clear is NOT fuel proof.  I sent an email to KBS asking about this product's ability to resist methanol and nitro methane.  The response I got was that the single part Diamond Clear was not formulated for chemical resistance.  You must use the two-part product to get any fuel resistance.

As proof, I applied some of the Diamond Clear to a surface painted with a water based acrylic.  I let the Diamond Clear dry for two days.  I dripped fuel on it (5% nitro), waited a minute or so, and wiped it off.  The Diamond Clear softened and was rather easily destroyed by the fuel.  I seriously doubt if waiting longer than 48 hours would have made any difference.

I have yet to find a single-part product that has much, if any, fuel resistance.  Only the two-part systems can make that claim.

[Paul Taylor]

Found this on the www.

methanol is commonly used as a solvent, especially in industrial and laboratory settings. It's particularly useful for dissolving polar and non-polar substances, making it versatile for various applications such as chemical synthesis, cleaning agents, and fuel additives.

The other solution is go electric. 🙃

[Ara Dedekian]

Polyurethane spar varnish has worked for me.  It yellows a little but it is fine.

       Who would have thought!!! I would have assumed the solvents in the varnish would eat the foam in a second. Tried it on a scrap piece of foam, then went a step further and tinted the varnish with powdered orange chalk (since the varnish has a yellow/orange hue) and applied it to the bottom of the wing. Then found a can of Benjamin Moore Super Spec alkyd paint, and based on both cans having the word, 'Urethane' on the label, I used it on the top; and it worked too. It should offer some protection as I used it to make a sign that would be in a salt air environment. It held up pretty well.

        Thanks for that tip Dave, all I have to do now is wait the two plus weeks for the alkyd to dry.

Ara

[Brian Stas]

Ara, just come back to flying combat, We never worry about fuel creep or oil soak...

[Steve Dwyer]

Refocusing on KBS. Researching the many earlier posts here on experience using one-part KBS Diamond Clear rattle can or open quarts there are mixed feelings. In general, however, many feel it will provide a "suitable" protection from Nitro based fuels. My interpretation of suitable is it will provide protection when raw fuel that has splashed on a leading edge or cowl is wiped off during the start-up process. I will attest to this from experience and add compared to butyrate clear it offers much better protection. I still would prefer a 2K clear over a custom project.

Steve

[jfv]

I have used EZE-Kote for fuel proofing on the rebuild of a nose section of my Oriental and it has held up quite well for a number of years.  I would let it cure for a while before I would expose it to fuel though.