Can I use an airbrush to paint a motorcycle?

August 1, 2010 5:44 PM

Can I use my airbrush to paint my motorcycle's gas tank?

I have a couple of motorcycle gas tanks I'd really like to paint up. One is in much worse shape than the other.

The one in worse shape is the one I'd like to start with, just for the "less to lose" factor. It's currently in pretty bad shape- a pretty thick coating of what appears to be hand-brushed? paint, with no clearcoat, a significant number of dents, but little rust. I'm able to get the current paint off- I can pretty easily coat the thing in paint remover and use a heat gun, steel wool, sandpaper, whatever, to get the current paint off. After that, I'm lost.

I have a small suction-feed airbrush available to me- I don't remember the brand offhand, but it's of decent quality, with a small compressor that removes water and such. I've tried to paint metal with a spray can before, and it went badly- even though I sanded and prepped the surface, I had very little control and a lot of overspray, and I got orangepeel all over the place. I think I need a pretty comprehensive introduction or walkthrough to painting metal- what kind of paint do I use? Do I need to wet sand? Do I need to do surface prep? Can I use this airbrush, or is it completely inappropriate for the job?

Thanks for the help! If I've left anything out, I'll be happy to update. If pictures are necessary, I'll take some.

posted by aaronbeekay to Sports, Hobbies, & Recreation (6 answers total)

Best answer: It's been a long time since I used an airbrush and I never got very good at it, but I feel fairly sure that it won't be very useful. Automotive paints are typically applied with much larger spray guns, paired with much larger compressors. Unless you want to invest in new equipment, I'd suggest you stick with spray cans and just refine your technique.

Paint is really the last step in a long process. You'll need to remove the old finish, fill dents with auto body filler (Bondo or similar), prime the tank with multiple coats of a rust-resistant sandable primer, and sand it very, very smooth with fine-grit paper. Abrasive Scotchbrite pads can help, too. The surface should be virtually perfect before you touch the paint can.

Even with excellent surface prep, it's difficult to produce a really nice finish right off the gun (or can) outside of a professional-style spray booth. If the finish dries quickly then you'll be fighting overspray and orange peel. If it dries slowly then you'll have insects and dust landing in before it dries. Lacquer used to be a great way to deal with these challenges because defects could be polished out after the finish hardens, but I'm not sure how available it is these days.
posted by jon1270 at 6:54 PM on August 1, 2010

I can unequivocally say that yes, airbrushes are often used to paint detail work on automobiles and motorcycles.

I can't, however, give you any details or good advice. I have to believe that there are some how-tos or google groups devoted to this sort of thing.
posted by chrisamiller at 7:24 PM on August 1, 2010

Just one small thing - before using a heat gun to strip paint, I really really hope there's no petrol left in those old tanks.
posted by wilful at 7:39 PM on August 1, 2010

Best answer: I've used an airbrush to paint several of my motorcycle tanks. I've used both House of Kolor and Auto-Air with good results the latter would probably work better with your airbrush. This might be a good place to start with the how-to.
posted by Tenuki at 11:06 PM on August 1, 2010

Clean it (if you have a body or paint shop nearby ask if they'll bead blast it)
Bondo (unless you don't care about the dents... They add character)
Sand it.
Rustoleum primer. Multiple coats.
If you're just going for a solid color, cans will probably be easier. You can get real nice paint in a rattle can these days.
Use the airbrush for any "detail work".

Best advice I ever got: Go to a junk yard and buy the hood off an older, steel bodied car. Use that to practice on. A hammer will give you dents to practice filling, too.
posted by gally99 at 1:40 AM on August 2, 2010 [1 favorite]

There are a number of tutorials and how-to's on the web for automotive painting.

You could paint the entire tank surface with the airbrush but it might be easier to start off by using a spray can (rattle can). You will, however, need to be sure that the types of paint you use are compatible (enamel, lacquer, etc.).

You said that the airbrush is suction-feed, but didn't say if it is internal or external mix. If it is an external mix, you will have a more difficult time at controlling the mixture because it will require closer attention to thinning the paint. Paint thinning is difficult to judge and requires a bit of practice. An internal mix will need to be opened completely for painting the larger surfaces.

Stick to the solid colors to start off with. After getting some experience, graduate to the metallic and candy colors.

There are many talents needed in painting. From surface prep to masking to clean up.
Practice makes perfect.
posted by Drasher at 8:20 AM on August 2, 2010