So my boss is restoring his 99 TAH0E (yeah, you read that right) and he is painting all of his ancillary small parts with Rust-oleum, DupliColor, or whatever shelf brand spray paint is available.

I am painstakingly going through the task of doing all of my small parts by mixing and shooting with a gun.

Am I wasting my time?

What's the difference between the two paint types and methods?

Will one last longer? Is one tougher or more durable?

Just thought I'd ask and see if anyone here has an opinion (LOL).

Thanks!

Wait till your boss needs to clean or especially de-grease those spray bombed parts.

I don't spray bomb anything under my hood that is important. There are just too many things that can damage the finish or that will cause the paint to fail completely.

Spraying with 2 part paint with a gun is a pain, but is worth the effort in the long run.

Spray paint has zip for durability compared to a 2-part paint. If you're painting something that doesn't matter, fine. If it's something that will see wear or chemicals, it will be a problem.

yet many praise stuff available in rattle cans from many restoration supply companies for many high "abuse" areas such as under hood and suspension items. are these sold only for "trailer queens" ? the adds for such products suggest not. and this does not include etching primer or two part paints available in rattle cans. so how can someone come to a correct conclusion for their needs ?

Spray a part with rattle and urethane with a gun. Then spray with brakleen or carb clean. You will have the answer. I have motors and suspensions running around well over 10 years, still look like new. We're talking control arms, axles, intake manifolds, etc.
Doug

All I can say is this guys, I've worked with rattle cans since the early 70's. The products out today are superior even to those lead based rattlers of yesteryear. I myself have painted K-members, shocks, rear ends, under chassis and small parts with Epoxy based rattlers or good old Rust-oLeum and others.

Like any paint job, prep and cleanness, application and flash dry times, and a reasonable amount of light coats and sanding in between and a top clear coat makes for a beautiful product. Do they hold up to chemicals, most do if applied correctly.
Chip wise, epoxy baked products have been durable, but still may chip on an occasion. Trust me when I say that.
The secret to painting most small items with spray paint is the type of cap that is used. Some caps can spray almost as wide as some spray guns and that makes for an even steven coat.
Keep your distance and apply a few light coats in between, that will get you there. Good luck.

Biggest difference between the two is the ability to catalyze the paints being sprayed through a gun. This enables the finish to produce a harder and more durable surface that will stand up to more physical abuse, chemical abuse, UV, high pressure wash, etc. Spray cans typically can't be catalyzed because the paint would set up and become unsprayable because it hardens. Although I think Eastwood does offer a catalyzing rattle can now days. But I doubt it can be used more than once.

Yes, many modern rattle can finishes are decent, but simply won't match the longevity of a two part finish. Never mind the ability of a gun to provide better coverage, better atomization, and more control over the application process.

If you want to do it once and plan on keeping the car for a long time, and don't mind the associated clean up, use 2 part paints. If you're preparing for a quick sale and don't care what it looks like when its out of sight or like to redo parts every few years, spray bomb it.

I think you'll be the "lone wolf" on your opinion when it comes to spray bomb vs spray gun

Catalyzed paint is molecularly different than non-catalyzed. Its molecularly 'cross-linked'. Google it. FAR superior for the reasons stated than a rattle can.

That's one of the reasons the 'Rustoleum' paint jobs are such a joke.
Even low end two part paints like Omni and Nason are far superior.

It's called marketing. Companies are good at it. In the end, a 2-part paint will be superior in chemical resistance as well as scratch and chip resistance. They are usually more expensive and much more of a pain to do all the setup and cleanup after the fact. I use spray paint for certain things, sure, just be sure to appreciate the limitations of the product before buying it.

No he won't...

Got 20+ years on rattle-can engine, suspension components...


Cleaned and degreased many times over the years...


Holding-up fine...

Eastwood I believe sells spray paints in a can that are catalyzed... which would solve the biggest issue with spray cans. For me, it depends on the part. Suspension and etc... always gets done with a gun and better quality paint. Engines, I still spray paint now and then, but only for the color, I will use something more durable underneath.

High grime areas. Sprayed lower control arms & brake calipers with rustoleum red spray can, aluminum on the diff cover. Other the a few
chips on the LCA, 4 years later still looks like new. It's all in the careful preparation. Lucky? Dunno. Whatever the reason I'm satisfied.

So I sprayed some suspension pieces with epoxy primer then some Omni and one piece got some runs I couldn't live with. I waited till the paint dried then put it in my blast cabinet. That dulled the finish. I then gave it to my buddy to throw in his hot tank. Two days did nothing. I had some pieces going to a chemical stripper so I gave him that as well. Of all the pieces I gave them they mentioned this piece in particular needed extra time in the tanks.

I know for a fact that anything from a spray bomb would have come off in my blast cabinet !!

No comparison!
As has already been said, it's all about the catalyst.
Rattle cans are no match for real paint.
It's so easy to shoot paint (talking suspension and underhood stuff) that there is zero reason to spend lots of time preparing parts and then to apply 6 dollar a can paint.

Took me many tries but I have come to realization that spray cans just don`t hold up. I tried many different ways.

the magic brand stuff from rural king and TSC is good stuff....dries rock hard AND holds up to cleaners and such....one drawback is it takes a long time to dry but its worth it

I spray all my engines with Mopar engine paint. very durable stuff.

I use rustoleum, various versions, for engine block, small parts, e.g. alternator bracket, suspension etc. and it works fine and chemicals haven't seemed to be a problem.

Urethane, 1 or 2 part, has a better gloss for sure.

If I had all my small parts ready and could paint them all at once, it might make sense to mix up catalyzed paint. But to cover/protect something as you go, rattle can!