Fuel Proof Black?

[T. Cotten]

Geez I hate paint.
Especially when I cannot apply it with a brush.

But since I do carburetors which quite often must be black,
I am once again searching for a better coating, as Memorial Day marks the beginning of the latest round of notoriously digestive 'summer blend' fuels.

Currently I am using rattle-can VHT epoxy, as it has been the only off-the-shelf coating that didn't wash off in P4gas. It has the advantages of convenience and touch-ups down the road, however it is a very fragile coating. (T'aint cheap either!)

Since I shall begin another round of testing in the next few weeks, I would greatly appreciate any suggestions of satin and gloss black coatings to investigate.

Many thanks in advance,


...Cotten

[yhprum]

I dont know much about it but what about a chemical conversion. Selenium dioxide is used on some brass/bronze to turn it black.
Cheers, Steve

[T. Cotten]

Steve!

I use selenious acid, but not for the appearance of a lacquer.

It only gives the appearance of heavy tarnish.
Stove black has its place as well, but still doesn't fill the bill for a like-it-left-the-factory appearance..

At least those conservation methods are not destructive like powdercoating (which can be attacked by P4gas!)

Thanks for your reply,

...Cotten

[exeric]

Tom, the Schebler on my Chief is painted with gloss black Imron and it's still hanging in there after 10+ years. It now has that perfect dull look that it didn't have when freshly painted. The guppy bowl is painted with Centari with hardner and it's peeling in some areas. I usually put Florida BP regular in it.

The bad thing about Imron, (in addition to the price) is; poor shelf life for the catalyst, miserable to mix, and it damages the nervous system. Other than those piddling details, it's great.

[bmh]

Cotten, have you ever tried any of the new generation of firearm finishes? I would try either dura-coat or the aerosol dura-bake from Laur weaponry. If it stands up to the abuse and solvents there it may just be the ticket.

http://www.lauerweaponry.com

This is also where I buy my parkerizing supplies. Best price i could find on mil-spec solution. They make it, I think Brownells and everyone else buys it from them and marks it up.

[Mr. Big]

Palmer's sez that the Linkert for mine should be black but just says "dull". For the VHT epoxy you mentioned, which "black" product do you buy for that "factory" look?

[T. Cotten]

Brian!

From what I can gather about the cost, and the additional labor and solvents to apply it,
I would have to charge $75 a carb to break even!

And if it is so durable, why do they prescribe a surface protectant to go over it?
I'm afraid I'll shop a bit more before I invest $50 just to see if it is P4gas resistant.

I would really like to stay away from anything I must mix and airbrush, as not only is the labor tripled, I must stack carbs up to do them practically without a lot of wasted mix. Been there, done that with Aerogloss over Variprime. (And P4gas ate that.)

I appreciate your reply, though!

...Cotten

[indianut]

Black Oxide is cheap and easy. I don't know how well it will take the fuel, but I'll bet pretty good.

[T. Cotten]

Indianut!

The problem with black oxide is that it doesn't look anything like L&L or Schebler carburetors' lacquers.

The AMCA judges would be pointing their stink-fingers in disgust.

Thanks for your reply!

....Cotten

[Chris Haynes]

Black Oxide is cheap and easy. I don't know how well it will take the fuel, but I'll bet pretty good.

Are you talking about Black Oxide metal finishing? I don't know it that would work on brass. Besides it would not look at all like paint.

[T. Cotten]

Palmer's sez that the Linkert for mine should be black but just says "dull". For the VHT epoxy you mentioned, which "black" product do you buy for that "factory" look?

Mr. Big!

Sorry for this late reply,
but it seems like your post just now appeared out of no where....

Schebler's later potmetal models were an admirable gloss that survives the decades, and quite resistant to modern fuels as well.
Linkert bodies were less glossy, but that is a subjective observation clouded by the fact that they were a rough bronze casting, and most often it did not survive.

I would settle for any gloss black that is as fuel-resistant as VHT, but more resistant to fingernails. And convenient to apply. And readily available to all for touch-ups.

That's asking a lot,


...Cotten
AMCA #776

[Paquette]

Tom--I have not tested this with fuels ( as I have no real reason to do so) But I have used a Rustolem High Temp paint that the label states is gas and oil resistant. As I said I have not tested it but it does give a nice finish--Michael--6671

[bmh]

Cotten, I see where you get the $75 for the duracoat, did you look at the durabake? at $25 for a 6 oz aerosol can it doesn't look outta line to me. Especially if it works. Note that it must be cured by baking. Clear-coats are optional.

http://www.lauerweaponry.com/item-de...TOKEN=44682412

I must also ask this. I saw in another post that you were testing samples of something on plate glass. That is not the way you are testing the paint is it? As they make the solvent package more polar bear friendly, coatings are becoming increasingly dependent on a mechanical anchor. The surface must be rough enough for the paint to get a good grab and needs to be free of any oxidation as that forms a boundary in your coating. Used to be the solvents would bite through slight oxidation, that's not the case these days. Honestly I don't think you're gonna find anything in an over the counter rattle can that's going to hold up to modern fuel. With the exception of hi-temp paint for cylinders and such I don't use anything from a rattle can on motorcycle parts, and I'm looking for a way to get away from those also as they just don't seem to have the durability they did some years back. Mixing small amounts of epoxy or catalyzed finishes is not the big deal most make it out to be. A Preval spray unit for $7 would probably have enough propellant to do 20 carbs, the bottle is already marked in ML's so its real easy to mix little amounts. Turkey basters work well for metering out catalysts and reducers. We use these at work for small samples and field touch ups and I've begun using them here for the small things that aren't worth dragging out all the spray equipment.

[T. Cotten]

Brian!

Baking is fine for bronze Linkerts, but I found out the hard way that it is not good for potmetal Scheblers. The real hard way.

(Guess why DLX113s are the most expensive cores on the planet, and the most expensive to refurbish: they caught fire off the ignition below them.)

At twice the price of VHT (without the other preps), it is still within consideration. (Whoops! Three times counting shipping. It will cost me nearly $40 just to test a 6 oz. can, hopeing that it will survive conditions for which it was not designed.)
Although 350F would guarantee tragedy, 180F for three hours might mean that extended time at a lower temp would do. Considering Flatty temperatures, it is amazing that potmetal Scheblers survived at all.

On to testing, please note that I use etched glass plate: ALOX-blasted for a mill profile.
Part of the plate I leave un-etched for comparison. (And a spot I can engrave for labeling.)

The fact that VHT's epoxy is so P4gas resistant is why I maintain hope that there is a superior coating.

Thanks for searching their site for an aerosol, as I couldn't find any!

....Cotten

[T. Cotten]

Tom--I have not tested this with fuels ( as I have no real reason to do so) But I have used a Rustolem High Temp paint that the label states is gas and oil resistant. As I said I have not tested it but it does give a nice finish--Michael--6671

Michael!

"Hard-Hat" Rustoleum was suggested to me a few years ago with great praise.
P4gas ate it for lunch.
I've still got most of the six-pack left.

Admittedly it is not the high-temp formula, so I shall seek it out, hopefully in a smaller minimum order! And also hopefully in something other than barbeque black, as most high-temp blacks tend to be.

Thanks for your suggestion,

....Cotten