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Automotive Paint vs. Spray Cans

Can anyone tell me if automotive spray paint (i.e. Centauri) has any advantages over spray can paint? Also, which is the best brand of spray can paint to use for resistance to gas and heat? I'm not set up for a spray gun, so I'll likely be using a spray can for my Witte. – Chris

When I painted my Mogul I did not trust spray cans to be the correct color. I got the Dupont number, and they mixed spray cans for me. It was expensive (at $10.00 per can), but I feel it was worth it and the color is perfect. It will get soft with gasoline, so I need to coat it with clear. It went on great and looks great. – Al

I can tell you for certain that the cheap 98 cent Kelly Green from Wal-Mart will shift towards blue when exposed to 300+ degrees on steam lines. I still use it anyway and just touch up the problem areas yearly. I've also had implement enamel from the local Farm & Fleet (IHC red) that actually peeled off in strips. If you spray bomb, Rustoleum is pretty good (except that you have to watch the second coat, it can and will react with the previous coat to give you a "crinkle" finish). – Allen

There's a trick to spraying Rustoleum - read the fine print on the can. You cannot spray a new coat after one hour or before 48 hours. In other words, you have to get all of your coats sprayed within one hour or wait two full days before spraying another coat. If you do otherwise, you'll get the dreaded crinkles and then you will have to start all over again. – Harry

I noticed that with Rustoleum, after maybe 10 years, it peels off and leaves the primer on and in great shape for the next paint job. You can brush paint Centauri but don't do it if it's over 60 degrees because it dries too quick. I know they tell you to paint when it's over 70 degrees, but I had good results painting my 8 hp Mogul with it and it was 40 degrees in the barn. The cold actually slowed down the drying so I could finish the job before the brush set up. You need to wear a good mask when you use the stuff. It's got some pretty unhealthy chemicals in it. Probably the most important part of the paint job is the prep work. Everything must be clean and oil free. Spend as much time on it as you need to get it right and it will show in your finished work no matter what you paint with. I have had good results with Demkote paint sold by Grainger’s. Also Krylon seems to be pretty good. Rustoleum by far takes the longest to dry. Good luck – Rob

If you want to use Centauri in hot weather (which we have a lot of down here in south Mississippi), use a high temp thinner. It lets the paint dry much more slowly and lets the brush marks flow out before it dries. If it still dries too quickly, you can add a retarder to it and slow it down even more. By brushing it on, you can add the gloss hardener to it and make it gas & oil proof. But if you’re going to stay in this hobby, get a paint gun and start practicing with it. I think you'll be much more satisfied with the results! You will also have access to an endless number of colors from DuPont, or Sherwin Williams, or Ditzler, etc. – David

What we found out (and were also told by our automotive paint suppliers) two and three part mix automotive paint is harder on the surface and is much more resistive to UV (sunlight). When we spray red on our field trucks (by can), it will start fading in about 4 to 6 months. Automotive paint will stay shiny for a very long time. It might make a difference for you if you are leaving it out for long periods of time. – Darryl

Lowe's building supply house has a spray outfit, Quart cup, 1/2 pint gun, air brush, hose and fittings, about $60.00. It's decent equipment, but the key is to keep it clean. – Chuck

I'm still going with automotive acrylics and hardener, but it sure is getting expensive. – Larry

Centauri is great, but will lift if soaked with gasoline for any length of time. Most any paint will do so except the three part urethanes. They are the best, but expensive and hazardous to use. They are very forgiving when sprayed, build up multiple coats quickly, and have a super gloss. NAPA sells Duplicolor acrylic enamel in spray cans. The color selection isn't great but it is as good as Centauri and sells for about $4.00/can. I weather tested it on my mailbox and it still looks great after a year. Rustoleum faded in less than 2 months in the weather. Also Rustoleum doesn't dry fast enough to remain dust and bug free. I used to get Centauri put in spray cans for $3.65/can plus the cost of the Centauri paint. You get about 6 cans to the quart plus a little left over. This is somewhat expensive but good way to handle small projects. For larger engines, bite the bullet and get an inexpensive HVLP spray gun. Even the cheap ones are great. I got the pressure cup type and this is more convenient for use around my messy shop. I have also found a spray gloss shellac coating to help in gasoline spill areas. It is not soluble in petroleum solvents. Just don't spill any alcohol on it. -- Jeff

I have to agree with Jeff. I used PPG`s version of Centauri and the paint did peel when soaked with gasoline. I used it on an Allis Chalmers and other than the area just below the fuel sediment bowl I have been happy. The tractor still looks good other than that area and has otherwise held up well. -- Dave

Did you add the gloss hardener to it? If not, gasoline will STILL soften it up. With a hardener, it cures out very fast, and then has properties much like urethane without the mess. After it sets overnight it is pretty much bullet proof, even on sheet metal fuel tanks. I have seen it wrinkle around gas tank necks but that is usually caused from the flux used in sweating on the neck and cap. But generally speaking, gas does not bother it. If it did, it wouldn't be worth much on a car. Every time you filled your tank, you would wash the paint off the quarter panel! – David

A few years ago, after a gasoline wrinkle showed up under the weeping check valve on my Hercules, I called Dupont and asked them about gasoline proof paint. They told me that they only had one type of paint that would be considered gasoline proof and that was "Imron". Imron, of course, is a three part urethane. I asked about Centauri and hardeners but they said it would still wrinkle if the gasoline was left to soak on the paint. PPG said just about the same thing. The key is "soak". A spill or two or three won't bother most cured quality paints, but an overnight soak will discolor the paint and eventually lift it. Just watch those leaks! Most good auto finisher supply houses will pack aerosol cans for you. Some cans and spray tips are better than others. You want the flat fan spray tip, which is usually a blue colored tip. I have mixed Imron and used it in a universal aerosol spray kit found in most hardware stores. It worked very well as long as the job is small. The propellant can starts to freeze up if you spray too long. -- Jeff

I have heard that when Imron hardens, it really hardens and doesn't come off easily if you need to strip the item for some reason in the future. I saw a tow truck at a body shop that was painted with Imron a good number of years before, and when they sandblasted it, there was still quite a bit of paint left on the truck. – Bill

Any idea what store I can buy custom spray cans at? Do they use compressed air as the propellant or propane? I have spray guns and the stuff to do gun painting but those cans are so convenient for little jobs. It would take me a week to cover everything in the barn, plus disposing of the waste thinners. I think that it would be nice to match homemade spray bombs and good paint in the RIGHT color. -- Rob

I get mine put into spray cans at my local automotive paint store. It’s not cheap, usually $17 to $20 per can. Depending upon the color, they will make any color in any brand they carry. Sometimes when I buy a quart, I will have them put some of it in a spray can. That way I have a perfect match for later use and it won’t be dried up two years later when I need it. -- Allen


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