Commando303

There's a small area of my bike from which paint is missing, and I wonder if it's idiotic of me to consider filling it in with nail polish... There's no chance this could do any damage, is there? I've read, on-line, that painting a bicycle involves disassembly, removal of old paint, sanding, using primer, etc., but I imagine all this is for people who wish to re-paint an entire bike. The patch missing on mine is probably about a square inch (less, maybe), though, of course, it's a very irregular shape.

Thanks.

randomgear

If it's a steel or aluminum frame, go for it!
If it's carbon fiber, ask the manufacturer.

ehilge

At my shop we generally use a little bit of Testor's enamel model paint if all that is needed is a little bit of touch up. Its waterproof and fairly durable. They also offer quite a few different colors so you should be able to find one to match your bike fairly well. The paint can be found at most hobby stores and shouldn't cost more than two dollars for a small container.

Camilo

I think this is a better option than nail polish too. So many colors, so easy to mix to get a better match.

Panthers007

For REALLY painting a bike* - both Testor's and nail-polish fail. Wrong stuff. Bot for touch-ups I'd suggest nail-polish. The nail-salon here has a zillion colors. And I mixed them for a good match for a very weird pain on my PUCH.

The best thing about n-p paint? It can be easily removed - totally - with acetone (finger-polish remover), whereas Testor's is very hard to try, try, again with.


* - Use the Search function in these forums for suggestions on painting a frame.

Commando303

Aluminum (maybe steel, where I want to paint). I've never heard of "Testor's enamel model paint," but I thank you for the suggestion. Do you have any recommendation of where to look for it? Is it something a typical bike-shop would have in its stock?

Thank you.

*The color I need is black.

Panthers007

Find a store(s) that sell models, etc. Like model airplanes, Dinosaurs, so forth. Call and ask.

cyccommute 

For small touch ups, go look for touch up pens at an auto parts store. Paint adheres better than nail polish. Testor's would also be better than nail polish.

demoncyclist

Nail polish is enamel. Testors paint is enamel. Touch up paint is enamel.

Panthers007

Regards nail-polishes - a good nail-salon will have a whole wall of different colors*. There's one in my small downtown-mall. I love scaring the old women there - long-haired Yippie strolls in and starts playing with the paints... The owner likes me though. I must be a taste of fresh-air. Muahahahaha!!


* Each little bottle contains a fine brush attached to the cap. Pick up the remover, too. It's a good source for acetone - cheap.

HillRider

Most Wal-Marts have a huge rack of nailpolish in a tremendous variety of colors, most of which are unknown to nature.

Testors model paint is available in an equally bewildering array of colors at any well stocked hobby shop. When I wanted to match the paint on my Co-Motion, I wheeled it into the local hobby shop and parked it next to the Testors display rack.

cyccommute 

House paint is enamel also but I doubt you'd want to use it on a bicycle

Not all nail polishes are enamel. Many are nitrocellulose dissolved in an acetate solvent. They aren't meant to be as permanent nor as durable as enamels or other polymer resins. Testors enamels are meant to be used on plastics and thus have issues with the type of solvent they could use...dissolving the polystyrene or polyurethane of the model would be bad Adhesion to the existing paint may not be as good as automotive paint that uses more aggressive solvents.

exRunner

I have a black bike and I use a black Sharpie for touch up. Seems to work fine.

Panthers007

Perhaps on my next foray to the mall, I'll stop into the nail-salon and pick up some pink nail-polish. What do you think? A red Trek custom-hybrid with pink polka-dots? I'll at long last have a name for the machine: Measles.

Mike Mills

Nail polish is lacquer, not enamel.

Commando303

I'll try to get either nail-polish or Testors. Thanks, all.

DannoXYZ 

Do this test, find a test piece for paint, like a soup can. Lay down a stripe of each:

1. nail-polish
2. touch-up paint
3. Testor's model enamel

wait for them to dry and rub the stripes with alcohol, mineral-spirits, acetone, lacquer thinner. That'll tell you which type of paint you want to use.

Panthers007

Well the acetone will take out nail-polish. That's why they use it. Not sure about the Testor's though. Because of acetone taking out the nail-polish, this makes the stuff perfect for touch-ups as if you make a mistake - it's easy to rectify. So one might wish to start with nail-polish to hone your skills as a touch-up artist. Once you're satisfied with your work, you can remove it and go for the more permanent Testor's paint. Or not.

conspiratemus

At our local nail-salon, the staff and the clientele scare me! More tattoos and piercings than I ever thought possible (and those are only the visible ones....)

ehilge

if you're worried about removing the testor's enamel, they do make a paint thinner sold along side the actual paints that works well to remove paint from unwanted areas. I use it for some of my hobby modeling projects. Unfortunately, I have no idea what this thinner is made out of so I'm not sure how it would affect the original paint on your bike. Does anyone know?

Panthers007

Without pouring it into a paper-bag and huffing it - can you say what it smells like? The chemist's way is to hold it away from you and use your open hand to waft the vapors towards your nose. If it has a pronounced odor, we can probably pin-point the main ingredient. If it has little odor - it's likely "mineral spirits" such as lighter-fluid. See if it's marked as flammable, too.

Don't do what the French chemist Lavoisier did when he discovered hydrogen gas - take a deep breath of it and exhale on a lit match. He wrote his report on his discovery from his hospital bed. Boom!

Mike Mills

That is ridiculous advice. I hope no one actually tries any of that.

Lacquer dries but does not cure (polymerize), so it remains soluble in acetone forever.

Enamels, like Testors modeling paints, cure (polymerize) upon drying, so once dry they are no longer soluble in paint thinner (mineral spirits). You may be able to remove it with acetone but , methylene chloride (paint stripper) will get it off for sure (along with everything else).

I'd have to recommend lacquer (nail polish) for small touch ups.

Nail polish is lacquer paint that has been formulated for brushing. It is relatively thick and has ******ant added to slow drying. The ******ant is a solvent that evaporates more slowly than acetone to allow the brush marks to level out before it hardens. This is good for brushing application.

Just be careful working around a tube. The slow drying time will allow the paint to run down the tube and/or around the tube before it dries. Go slowly. You can also thin the nail polish wil acetone. Thinning it will mean a thinner coat that dries faster. You may need more than one coat. You have to experiment to get it right.

Dr.Deltron

MM seems to know what he's talking about.

For me, if it needs "touch-up", it's ready for all new paint.

But I did do some touch-up on the Merlin, ... with a black Sharpie.

Commando303

Agreed: Mike Mills sounds to know what he's talking about. I'll try to had out to a pharmacy soon to see which nail polishes are available. If it turns out none can be had very cheap, I might just go for the Testors. I do like the idea of being able to remove the former with acetone (or, "nail-polish remover") even after it's dried, and I'm pretty sure nothing floating around in nature will strip it off, alone.

Mike Mills

Don't forget to do a compatibility test in an inconspicuous area. We have no idea what type of paint was used on your bike. You want to be sure the touch up paint won't dissolve or damage the base coat(s). do a test in a small, inconspicuous area before committing to repairs on a more conspicuous location.

Clean the area before applying the touch up paint. 90+% isopropyl alcohol would be a good cleaner. It'll remove any wax or road tar/film that might impede adhesion between the paint and the frame. Again, start with a test in an inconspicuous area first.

I hope this helps in some way.

I'd like to see the faces of the security guards watching you on the monitor as you go over to the nail polish counter and try to find the right color. They are just NOT going to understand. You'd better explain the situation to the cashier during check out. She'll set them straight. Better still, wheel your bike in with you and color match against the actual frame. :-)