How to Spray a Car with an Aerosol Can

Compressor-less all aerosol repair job review.

Before I say anything about my findings in the all aerosol repair I have to make something clear. This is not the “best” way to do a repair, but I feel it could be the “bestest” for some people. Buying a compressor and using a real spray gun is going to be easier, faster, and cheaper in a long run if you are restoring a car. However, I found these new generation REAL 2K products in an aerosol can to provide remarkable performance and very close to spraying with a gun.

If you wanted to “dabble” in auto paint and get your feet wet, if you have a small project it could be the answer. Even if you are having a shop paint your car but you are prepping it, you could get it ready with some spot repairs or even a whole panel using these real 2K primers and have a quality job when done.

These are a BIG difference from 1K junk “rattle cans” boys and girls, these are REAL automotive paint products in these cans.

I started the project with a 08 Honda fender that was being thrown away (your local body shop should have piles of fenders like this that they would be happy to give you!). I repaired a dented area in the front just as I would any other repair. The filler was left in 180 grit as was the feathering of the OEM Honda paint. As you may know, I like to abuse products in my tests to see how far I can push them. In this case I took a brand new piece of 40 grit paper and sanded a portion of the filler to see how the primer would fill it.

Here are the products used: Rubber-seal RS-586 non iso 2K primer aerosol , S-W waterborne AWX basecoat and a “Pre-val” to spray it, and Rubber-seal RS-588 Urethane 2K clearcoat aerosol.

Rubber-seal link
Sherwin Williams Waterborne link

Pre-val link

One thing I don’t like about the aerosols is that you are limited to that little mystery amount in the can. I don’t know what is in them but I know that in a regular aerosol can there is barely four to six ounces of product as I remember. That isn’t much, and again, in the grand scheme of things these aerosols are a looser at about $20 a pop. But again, they aren’t for a guy to leave his gun and compressor collect dust. It is way more convenient to use a gun, you have so much more control. That is one thing that really bugs me about the aerosol. But then again, if you have a particular project that is worth twenty bucks to you to get primed, so what if you throw away a half empty can?

When I primed up this fender I wanted to see just how far this can would go. I primed the fender and then went out and sprayed a small Toyota Corolla hood. I was barely able to get two coats on about half of it, along with my four or so coats on the fenders filler work. I figure I probably could have gotten the whole hood “primed” with the can. One problem, it was very thin, no more than a mil and a half or so. I was going so fast to try to cover the whole thing it was just too thin. But that kinda gives you an idea of what you can cover. On the fender, you can get as much as any other primer in build, I filled those 40 grit scratches without a problem and blocked the primer just as I would any other 2K urethane or iso free filler primer.

By the way, the fan on the can is about 5 inches.

The fender was prepared just as any other blend in the shop would be prepared. It was washed with wax and grease remover, primer blocked with 180 then 240 then 320 and then finished off with 600. The rest of the OEM Honda paint was sanded with 800 on an orbital sander with a foam interface pad. These pads fit between the sanding pad where you normally put stick your paper and your paper. It gives the pad and paper a “cush” so it goes over the shapes of the fender better without cutting thru on edges.
After this the fender was washed again and blown and tacked like any other repair.

The next part is where I again, pushed the envelope and grabbed the waterborne basecoat. I could have done this in solvent borne regular old base coat. But being we are all going to be using waterborne I figured I would give that a go with this “preval” sprayer. The whole idea of this was to see what the average home hobbiest could do with this stuff right? I figure if I can shoot waterborne with this system it would demystify the water borne a little for the home hobbiest.

The only thing I did different with the water borne over solvent borne was to use a “Rapid air” drier to blow air on the paint after spraying.

The problem with water borne is that the solvents don’t like to flash off, and nothing messes up paint work more than trapped solvents. This stuff will take forever to “dry” if you don’t help it. Blowing air over the surface does next to nothing because of the low pressure area on the surface. Like a bug can sit on your hood as you drive down the road, the solvent in the paint just sits there when you blow air over it. This “Rapid air” device makes the air “tumble” for lack of a better term over the surface “pulling” out the solvents in the paint film. Anyway, with it the waterborne base flashes off very fast, worked like a charm.
We are spraying water borne at the shop, but I am not. I am not painting these days so the water borne was experience was brand spanking new to me.
So, here I am spraying my first coat of paint and it looks like CRAP. Oh my God, that PreVal was working like CRAP with that water borne. It just couldn’t handle the thick water borne paint very well at all. I have seen these things work well, I know they do, but with this water borne it wasn’t working at all. It’s vent hole would get clogged up and after a short spray it would stop all together. So I had to hold the bottle containing the paint with my left hand and the sprayer in my right with the pick up hose going down into the paint! You can imagine how difficult this was to spray this fender two handed, but it would work. The first coat looked horrible, like I had sprayed over wax or something. It looked absolutely horrible. I have since learned that it sort of looks like this out of a gun as well on the first coat. Well, the Preval doesn’t have a nice fan like a gun, and with the thick water borne sort of “falling” out of the sprayer onto the panel, it REALLY looked bad. I was so disappointed that I forgot to take photos, I figured the whole project was a waste of time at that point. But I just kept on going figuring that I had learned something, that waterborne was hopeless and I would go on to testing the 2k clear and hope that turns out better.

I did my best blending the color out and went on to clear it with the Rubberseal 2K aerosol clear. Again, I had a hard time. It sprayed on nice, but I put it on a little heavy being I was trying to apply it as wet as you would with a gun. The fan is quite a bit narrower so to keep it wet I was pounding it on. I did get a couple of sags but overall it looked pretty much like any other urethane clear coat.

The big mistake was going for a third coat, being you have no idea how much you have left in the can I ran out after a few passes and left the fender looking horrible with a large dry spot thru the middle. Of course if I sprayed the stuff a few times I would get the hang of it and I feel it could look much better than it did with a little practice.

“Out of the gun-done”. or should I say “out of the can-ran”

I have to tell you, I was blown away at how good the thing looked! The clear, it looked like crap as I said, but the blend, holy cow it was absolutely, without a doubt, invisible! The Preval sprayed sort of like a “drop coat” where you drop pressure in your gun to distribute metallic. The blend as FLAWLESS, not one bit of mottling, nothing, it was absolutely invisible!

Way out at the rear of the fender there are some strange dark spots of color but even those take a close examination to see them. But in the blend area over the wheel well it is perfect. I was amazed at how good it looked after how bad it looked before I applied the clear.

The next morning I couldn’t wait to get out there and do a lacquer thinner on a rag rub test. It passed with flying colors! This my friends is REAL 2K urethane clear in an aerosol can!

At the end of the day after I shot it I sanded it with 1500 then 2000 and buffed it just as I would any urethane clear. It performed exactly as a urethane clear would and buffed to a beautiful shine with a pass of the buffer. I sanded out the sags, some dirt, and it performed flawlessly. I mil checked it and found 2.5-3 mils of clear on it!

After buffing.

Right at the blend.

I am telling you, these 2K epoxy, filler primer and clears can provide you with a heck of a tool for painting small items.

Get a hold of Rubberseal thru their web site to find a dealer near you. There are many other brands available check with your favorite paint and body supply store to see what they have available.

Hope this info can help you take some chances and get out there and play a little. Remember, you must use a proper respirator and have good ventilation using these products. Protect you AND your family in the house if you are shooting in the garage.

Have fun!


106 total views, 1 views today