Quick question, whats the best way to paint a basic aluminum frame. I want to pain my Trek 4300 Black, and was curious what was the best way to go about doing it. Is it something I can do with like Krylon spray paint or is it a hassle like taking it to an auto shop. Stripping it down isnt a problem since its already mostly apart.

If you really want it to look good and prepared to spend $$$ on it, you should have it professionally done..

Doing it yourself, is also good.. But in order for it to be as good as those painted in the auto paint shops, you need the right equipment(compressor, spray guns, paint, etc.) which will cost you $$$ too.

Using spray paint from a can may still produce good quality, but I'm concerned of the longvety and quality of finish. The spray paints tend to chip off too quickly.

Yea, I'm ok with a not so durable paint job, this will be a beater/trials bike so i just wanted the bike to look somewhat uniform. Would krylon stuff work at all though and does it in any way hurt the frame itself?

Dude, if it chips, then just re-spray it. That's my plan.

are you using krylon spray paint?

You could try some spray on bed liner. Sure, it might be heavy, but it will last.

You can actually do a pretty good job using rattlecans, but I would avoid Krylon... It never really seems to fully harden, so it always has kind of a tacky feel.

Go to an auto parts store and get touch-up paint. I think a common brand is Color-Rite. Use the same brand primer of whatever you get, otherwise the topcoat might attack the primer layer.

Give the frame a wipe down with acetone before painting; this will degrease it.

Carefully mask areas where you don't want the paint to go. Stick dowels in places like the deraileur hanger to keep those threads free of paint.

The toughest part is figuring out how and where to hang the frame while you paint it.

Wet sand with 400 grit wet-or-dry sandpaper between every coat and allow to dry. Wet sand the final coat with 1200 grit wet-or-dry, and follow it with rubbing compound.

Let it dry a few days before building it back up.

The trick with rattlecans is how thick you spray each coat. The instructions say to lightly mist. Not quite. The secret is to spray the heaviest coat that the paint will support without running or sagging. And it's a very fine line! Practice on some scrap pipe, or even cardboard, to get a feel for it.

If you're willing to go through the trouble, you can get some truly suprising results. And the bulk of the trouble is all of the wet sanding and waiting.

The other problem is the weather. Winter is the worst time of year for any kind of painting. The temperature range listed on the paint can is actually there for a reason. Unless you have a heated shop or garage (wear a respirator!), this could be the reason to have it done professionally. With this in mind, look into powdercoating. It really shouldn't cost too much, especially when you add up paint, acetone, masking tape, sandpaper, respirator/filters, rubbing compound, time...

Best of luck! And post pics when you're done!

-Erik

Insure that you have done some sanding on the frame before you do any spraying. The 400 grit mentioned above is good. You need to have a surface that the paint will adhere to. Thus the sanding. Also, call around to some of the automotive paint supply shops. They cater to the local body shops. You can now purchase the high quality automotive paints in spray cans. Then you will be getting a good quality paint.

All this said, give the Color Factory a call at 1-800-62-GLEAM. He will paint your frame for $130.

A guy on this board named Kerk did his bike a while ago and posted pics of the project, which came out very nice. I'd track him down and ask him what he used, because he researched all that before he started.

Pretty much what gazedrop said. If you're not sure how thick the coats should be, err on the thin side. Better to do too many thin coats than too few thick ones (not only will it look better but it should last better too). It's a good idea to put on some clearcoat too (at least five coats), this is harder wearing than the color coat and will protect from minor chips and scratches (better to polish off the clear than the color).

I've painted two BMX frames recently, with varying results. The first I did quite quickly, with rattle can primer and top coat. I didn't let it cure enough between coats or after I'd finished, and it chipped VERY easily (like with a fingernail). The second one I used the same primer, but with Humbrol enamel shot through a compressor, rattlecan clear with funky metalflake particles suspended in it, and regular rattlecan clear on top. Having learned to wait between coats it turned out much better, but I didn't put enough clear coats on to cover the metalflake properly (but since you probably won't be using metalflake, 5 or so coats will be plenty).

I painted mine with spraycans a while ago it turned out fairly well..
Here is the thread on it.
https://www.bikeforums.net/showthread...3&page=1&pp=15

I have sprayed my frame with rattle cans. I am not really bothered about a perfect finish.

If you use primer it can be applied much thicker that colour without dripping. You need to spray the colour on a lot thiner or it will drip, this has caught me out where I sprayed the colour on like I did the primer and got drips

I used a lot of clear coat as well.

One think to think about is drying time, the more time you can invest in painting so you can do more thiner coats the better.
Also the more time you can leave the paint to dry the better. Mine took a few months for the paint to reach full hardness.
If you can spare the frame for a week or two hang it somewhere warm. This will hopefully avoid any damage when building. When the paint is fresh even tiny stones will damage it.

I used Rustoleum Rattle cans on my bike.

It was an abandoned frame, so the paint was pretty beat up and scratched in places. First I sanded down teh frame with 120-240 grit paper. Then I used primer to coat the entire frame, followed by an ultra flat black top coat. The flat paint seems to hide some of my errors well. The whole project came out well. I could post some pics later if you would like.

As far as durability, it is a mountain bike, and has seen it's fair share of abuse. The top coat has done O.K. there is some cable slap on the top tube where teh top coat was knocked away; however the primer coat is still intact. I stil have quite a bit of the paint left, so I will touch up the frame when teh weather gets warm again (it is -10 here today).

The total cost of the paint job was about $10 including the spray paint, sandpaper, newspaper, and tape.

Enjoy your project.

By the way, my frame is an old Trek Steel frame. I am not sure how the newer aluminum frames woudl handle the sanding.

Thanks for the kind words! Here is the link to the previous thread...
Bike Painting

The paint has held up pretty good so far.

I would not use Krylon if you want a good paint job but rather a two part epoxy paint such as Emron. Then apply it with many light coats of paint and then shoot a clear coat. This will give it a real flash look. But my favorite coating is powder coating. This is bullet proof coating. It can be done at many powder coating facilaties in most cities. It is powder that is attracted to said frame which has elecetrical current passed through it attracting the powder which in turn leaves a nice flowing look like enamel paint(like womens fingernail polish)

compressor....spray gun....water catch....correct paint.....very good results if you spray MANY lihgt light LIGHT coats......very good results