How To Paint Aluminum?

[Takedown]

Ive been thinking about painting some aluminum parts on my r/c's lately but I really have no idea what way to approach it? Theirs anodizing and then theirs regular spray on paint with an overcoat. I really want to avoid anodizing because of the fact that it looks to be a real hassle. Is their any way to apply a spray on type of paint with high gloss and apply a durable overcoat on top of that to give it that shiny look and wont scratch off easily after deanodizing?


Thanks In Advance.

[lincpimp]

The best thing to paint al is to get it very clean, lightly sand it (400grit) and apply some zinc chromate etching primer. You can get it in spray cans for easy usage. It is thin primer, so it just coats the metal and etchs into it. After it drys, scuff it with a red scuff pad (scotchbrite - 3m name) and apply some decent enamel paint. I like spray paint for engine blocks, dries hard and shiny. Not sure what color you want, most auto parts stores have a selection.

You may have to look around for the zinc chromate primer, but it is available.

Not sure if i would use a clear coat over the enamel, it dries very shiny if applied properly, use light coats and warm the can in a bown of warm warter before you spray. And shake well!

[Takedown]

But what if the part your spraying have alot of ridges? That would take awhile with sandpaper grit.

[mikey09120]

Originally Posted by Takedown

But what if the part your spraying have alot of ridges? That would take awhile with sandpaper grit.

thats why my dad has a sandblaster. most engine repair shops have one. ask to borrow it

[JThiessen]

Originally Posted by Takedown

But what if the part your spraying have alot of ridges? That would take awhile with sandpaper grit.

I'd save yourself the headache and get them anodized or better yet - powdercoated. Our local powdercoater will do small parts for about 10 - 20 bucks a part, as long as you are using one of thier standard colors. I even had some done for about 5 bucks a part - he just threw them in with another customers batch - I didnt care that much about the color on those, but you pay for what you want....

If you are trying to clean up a piece that has lots of ridges, for example a heat sink, you will be best off getting it sandblasted. Second would be a chemical prep - but you have to have the right chemicals for that, and it would be expensive to obtain all the right ones. Next would be to go purchase about 10 of those stainless wire wheels for your dremel and go to town on it. Once you are done removing material, put on some rubber gloves and clean it thoroughly with denatured alcohol. Dont get any fingerprints on it....oily residue is very bad.

I'll second the "no clearcoat". Todays paints dont need it.
Getting any paint to resist scratching is quite a challenge. I've tried baking parts after painting, and had maybe a 25% success rate with it. You really need an advanced paint that is mixed specifically for that to make it work.
In the end powdercoating has been the best thing I have used.

I found my powder coater by talking to some local bikers - they all use powdercoating for their custom choppers.

[_paralyzed_]

sandblasting won't pit aluminum?

[JThiessen]

No - you use a different media and volume rate depending on the material. Bead blasting is actually more common now than sand blasting.

[rootar]

prep is everything, you want it to last and hold up you gotta take your time and do it right, dont skimpy on the sanding, make sure you get it all.