Bicycle Spray Paint 101
If you want a really nice professional quality paint job on your bike, take it to a professional. If you have a beater, spray it yourself and live with the lovable imperfections.
Here is a sampling of advice drawn from the online collective:
Of the conventional spray cans, Duplicolor and Plastikote are the most consistent quality.
One option that costs a little bit more is to get a Preval spray canister. It is a jar that you screw a propellant canister onto, making anything into a spray can. That allows use of more durable automotive paints that are only available in non-propelled variety.
Preval canisters are just like normal spray cans as far as disposal is concerned. You will need to read as many datasheets as you can get for your particular paint, as some will require thinners/reducers/activators.
You will want a minimum of a NIOSH approved paint mask, and a lot of airflow. Remember when they write the datasheets they assume a constant airflow of 125 cfm through the paint room at 70 deg. At that ammount of volume the threat to breathing is minimal if any. One item of note about urethanes is the medical hazzard is not so much the particulates as the fumes. The particulates are filtered by your propper mask, but the Iso-Cyanate hardener is a neurosystem alergen to some people. You should only be able to smell it ever so slightly if anything at all if your airflow is sufficient.
Duplicolor ceramic engine enamel clear. Very high quality and durable. You could also check out Eastwood, they have many top quality paints.
SEM – they also have a new basecoat line. I sell autobopdy supplies for a living, dollar for dollar this is it. Multiple gloss levels too.
Give Rustoleum Appliance Epoxy paint a try.
I use it on anything metal, it bond better than most paints and hold up to beatings. I sprayed a Jeep frame and axles and suspension parts, and they held up great to offroad abuse.
If you want black, use a product called POR-15 then cover it with their chassis black. It needs no primes and can be put on straight over bare metal as it’s a rust preventer. This would be perfect for a mountain bike.
POR is a killer product in non-uv applications. We use it in the body shop for coating trunks and insides of body panels. It however is not the best adhesion promoter for a paint finish. A bottle brush with it will be a nice touch for tube junctions internally, but it is awkward to apply to a bike.
The product I prefer for frames is Extend.
Clear: automotive wheel lacquer…not too expensive, very clear, and super durable
Assuming you want to use spray cans, your best option is to use DUPLICOLOR brand LACQUER available at most auto parts stores.
You’ll need 1 BIG can of grey sandable primer, 1 can of base coat (if the color requires it… many do… read the can), 1 BIG can or 2 SMALL cans of the color you want, and 2 or 3 BIG cans of clear LACQUER. This will cost you about $50.
INSTRUCTIONS (for Beater Bike job)
- Shake can, aim at bike, spray.
INSTRUCTIONS (for Optimal paint job)
- After completely disassembling the bike have it sandblasted to remove ALL the finish. If the frame is aluminum, it should be walnut shell blasted, or you can chemically strip the paint. Just make sure all the paint is OFF the bike.
- READ THE CAN INSTRUCTIONS, then spray it as soon as possible with grey SANDABLE lacquer primer. DUPLICOLOR brand paint is all lacquer, I think, and you can get it from your local autoparts store. Buy the BIG cans, not the small ones. Apply at least 1 full can, in coats, 15 minutes apart. Don’t worry about light runs for now.
- Wait at least 48 hours. There is a difference between dry paint and cured paint… it needs to be cured. Sand the primer using 220 grit aluminum oxide paper (white in color) or wet/dry paper (black in color) until the surface is smooth. It shouldn’t take much unless you have a lot of runs.
- Using a tack rag, lightly go over the entire frame (don’t rub!) to remove the sanding dust.
- Apply several coats (3 or 4 perhaps) of the base color (if necessary), then color of your choice. Make sure the frame is completely covered. Follow the directions on the can. Again, use LACQUER, the same brand that you used for primer. Apply coats 1/2 hour apart. Be sure you cover every part and do NOT get runs. If you get runs you are applying it too heavily.
- IF you wish to add decals, wait at least 8 hours, apply the decals, then continue. Make sure that you avoid touching the new paint as much as possible and to make sure there are no marks from water or “sticky stuff” on the frame. If you don’t want to add decals, continue immediately…
- Do NOT sand the color coats. Apply the LACQUER clear coats, perhaps 2 full cans worth, coats 15 minutes apart..
- Let the frame alone until you can’t smell the paint anymore when you get up close and take a big whiff. If you can smell it, it ain’t dry! This will take 2 to 3 days at least.
- Wet sand the entire frame CAREFULLY with 800 grit, then 1000 grit sandpaper. Make sure to keep the paper wet and to wipe away the white slurry that forms. If you start to see the color in the slurry, STOP! You have sanded too hard and reached the color coats. Repeat steps 5, 6, and 7, then try again. Don’t try to “touch up” the area, it will look terrible.
- Using white paste polishing compound, follow the directions and polish out the whole frame.
- Do NOT wax or wash for at least 10 days.
- Whenever I paint a bike or something like that I use different caps than the ones that come on spraypaint. Various caps that are usually used for graffiti murals can give you a wider radius of spray, and if you hold the can upside down you can spray out some of the aerosol to reduce the pressure. makes the paint apply a little more evenly.
Enamel over lacquer; but the reverse is not true. Can’t do lacquer over enamel.
The difference between the tqo is that lacquer dries by evaporation, while enamels dry by a chemical reaction. Lacquers dry faster, but enamels are more durable, especially when clearcoated.
As far as brands go, Duplicolor is a good quality spray.
- For safe and easy removal of rust from iron and steel, Naval Jelly is useful for preparing metal surfaces for painting.
- When sanding the paint to get the bike ready to paint, make sure that you do not go through your paint! Also, don’t make the paint too thin. If you do, you may be able to see through it.
- When wet sanding, make sure you don’t go through the paint, by drying off the area that you are sanding with a (paper) towel, and survey the area to verify that it looks correct. (Not too thick; not too thin).
- The quickest, most efficient way to remove the existing paint from your frame is to use a heat-gun and paint scraper. It’s easy, safe, chemically free, and clean-up is a breeze. If you live in a community with a Tool Lending Library (also known as a hire shop) you can probably find these there.
If you have an angle grinder, the wire wheel attachment will blast off the paint without damaging the frame.
A wire brush for your drill works well too.
- Do not mix different paint manufacturers (be that for primer, primary paint and lacquer) unless you have knowledge that they are compatible. This is because the 2 types of paint may react with each other.
- Even 24 hours after painting, do not lay your frame on a carpet or put it in clamp. This will distort the paint, which is still very soft, and will be imprinted with the pattern in the carpet, for example. 
WHAT YOU’LL NEED
- A bicycle to paint.
- Some basic hand tools to disassemble the bicycle, (wrenches, screwdrivers, etc).
- Sandpaper/sponge, (80 grit, 220 grit, and 1200 grit).
- Windex or other Glass Cleaner
- Razor blade, (helps when removing old decals, if present).
- Hair dryer also works wonders with old stickers and its less likely to cut you in the process
- Masking tape, to cover up certain areas if you are applying different colors.
- A piece of stiff wire to hang up the bicycle with.
- Primer (about 2 cans for a large bike).
- Paint of desired color (again about 2 cans for a large bike).
- Clear lacquer coat, one can should do.
- A clean, well-lit place to work, with good ventilation (remember: don’t destroy your skin, lungs, and eyes over a bike). 
If you go with PreVal
Buy one PreVal aerosol cartridge/bottle and one extra cartridge in case you run out of air. The auto paint store should have those. You’ll need a mask too, get one made for paint fumes, not just a dust mask. Those are totally worthless. You’ll have a lot of overspray with a bike frame, so use a fan and/or drape some plastic drop sheets. Wait till it’s fully cured, not just dry but cured, to reassemble or you’ll chip it out around the seat clamp and forks. If you get spots that need repair, a run, fingerprint, bug etc.. you can finish sand with succeedingly fine grits till it shines up.
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