how to paint a small Aluminum box?

[ahgu]

I have a small Aluminum box (4x4x8") with electronics inside that I want to give it a nice finish. I tried with water based latex paint and acrylic oil based paint. I found the even though the oil has stronger smell, it gives a smoother furniture looking surface. The latex stays sticky and rough.

Should I go with oil for better look and feel?

How can I paint it with a professional smooth finish? What are the rules I need to follow?

I used primer and have brush, roller. Only simple equipment. Can I bake the paint to give it better look?

thanks Andrew

[Charles Spitzer]

spray can?

did you acid etch prime it first? that will get it smoother, and also get the paint to stick to Al better.

you can also powder coat it. harbor freight has cheap tools to do this.

[firstjois]

I "do up" several kinds of metal boxes for the nephews make them GI or "camo" and their names. I spray a f ew very thin coats of Krylon until I get good coverage. If the can describes some kind of pre-coat (wipe with rag soaked in vinegar might have been one) I do that, too. Names and other USMC or Navy insignia I add with arts and crafts acrylics (two ounce bottles) and when that dries I use Krylon's matte finish (couple of thin coats) as finish.

Nothing I've tried so far beats the Krylon (or an oil based spray paint) for smooth even coverage. But once that's done I've been able to use just about any paint around next. And I always like a finish because different kinds of paint have different levels of gloss and the matte evens everything off.

Josie

[leonard]

hi I tried this a few years ago. I found the best place to ask is an auto paint supply company (here in the Washington/Baltimore area that mattos). there are special primers for aluminum. the car paint looks great when sprayed on with a though away sprayer(also sold at mattos).

[Mike Marlow]

Agreed. Etching is essential with aluminum. Follow that with a sandable primer and put a couple of good heavy coats on. Lightly sand it down with

500 grit sandpaper to make it ready for your finish coat. Use simple spray bombs from your local hardware store. The etching primer may be something you have to buy from an automotive paint supply store and it's quite expensive. Expect to pay around $10 for a spray can of it. Use it lightly, but evenly and fully on the bare aluminum. The sandable primer is definitely available at any hardware store and is only a few bucks.

This is definitely worth considering. Powder coats do require the same primer preparations though, so they will not save you the above steps.

If you decide to spray paint it, do a google search in this group for past posts that give a lot of helpful advice on getting a good finish with a spray can.

[Mike Marlow]

Krylon does indeed make some good paint as far as spray bombs go. Ace Hardware's own label is good stuff as well. Don't know who makes it for them - for all I know, it could be Krylon.

[ahgu]

I put on "clearn metal primer" . I don't know if it is the acid etch prime you talking about. It spray on a thin layer of white stuff.

Is it true that I have to stick with oil based paint for good smooth surface? and I have to use a sprayer? Water based Latex paint seems not smooth enough. It is soft and sticky too.

Also, I need to get a spayer to spray on the paint, instead of a little roller?

[Lew Hodgett]

Find a marine chandlery in your area, they will have what you need.

1) You need to etch the surface. 2) Apply zinc chromate primer (yellow color) 3) Apply finish coat.

Having done this a few times, I certainly would check out powder coatings.

There are shops that can/will do small jobs, especially if you are willing to wait.

HTH

Lew

[Charles Spitzer]

you want to read the label. you're looking for acid etching primer, something like

is too thick, too soft, and won't level out to what you're looking for. it's best with a sprayer, not rolled on.

[ahgu]

For sprayer, There is air sprayer and airless sprayer? What is the difference? Which one is better? Sorry for the newbie question. Would you recommend some good sprayer for a small job on bare Aluminum? thanks Andrew

[Charles Spitzer]

for doing 1, rattle cans would be best.

for doing a bunch of small boxes, i would probably use an airbrush. that would do a good job shooting your camo patterns too.

for doing thousands, an airless sprayer.

the cost goes up in that order too.

btw: you don't want to breath in that etching primer. use a good mask designed for vapors. buy that in cans.

[ahgu]

maybe I will find a local paint shop to do it for me in quantity. I cannot bear the smell.

[George E. Cawthon]

Use paint remover to remove everything down to the bare metal. Then spray with cans of red or gray undercoat and final color of automotive paint. Krylon is a good brand and dries almost instantly with little smell. If you want to get technical you can get enamels or lacquers, and while the former are more chip resistant for cars, lacquers would be better for your project.

And no, you can't bake any paint that you put on with a roller, beside wouldn't that ruin the electronics inside?

[ahgu]

Will I get smooth coverage with Krylon? Should I spray on several thin layers?

[Mike Marlow]

No. Spray on several wet coats. Just shy of running or sagging. Imagine yourself stretching clear plastic over your project. You want your spray to go on that way. Watch your spray pattern as you apply and make sure your passes blend in together. Again, a lot of stuff has been written up on this in the group. Do a google search for it and you'll find a wealth of information.

[John Emmons]

If it's aluminum, why not just have it anodized? It would have to be easier than most of the painting methods I've read about in this thread so far.

John Emmons

[ahgu]

I am actually thinking about anodized. Paint is too much trouble. Even though it has a huge color selection. I have no pro tools and space and environment to do it.

-Andrew

[Doug Miller]

This is a woodworking group. Perhaps you should post your question in a metalworking group such as rec.crafts.metalworking (followups set).