Enclosure Finishing Question - clear primer?

[tracer03]

I'm working on a build for a friend's cake day present - building him a yardbox - and I wanted to go bare aluminum with black lettering, then gloss/seal over the top. I kind of wanted the aluminum to show through - the enclosure is lightly polished but still has a bit of that 'patina' to it, because I wanted it to look 'old'.

The black lettering will be hand-painted enamel, and I want to make sure it adheres well to the enclosure. Is there a 'clear primer' for aluminum? I've found Rustoleum 'Bare Metal Primer'' online, but it looks to be colored.

Just wondering if anyone knows before I stop at the paint store on the way home from work today.

Thanks in advance!

[rocket88]

If you're going bare aluminum for the enclosure you don't need to use a primer. Paint your lettering on and just clear the whole thing afterwards. Just make sure the clear will not react to the enamel. I do this with my etched bare enclosures. After etching I paint the etch then clear on top.

[tracer03]

Thanks - any particular brand of clear you're fond of?

[rocket88]

Is use automotive paints exclusively. I find them to be fairly durable, and not too expensive. I also bake each coat to speed drying time, remove all gases in the paint, and despite the debate I find the point to be more durable when I bake it vs when I let it dry over time.

[Beaker]

Zach is right, just use cheap spray can acrylic auto laquer - use as many coats as you want then bake it at low temperature in your oven for a couple of hours. You don't need to use any form of primer at all.

A couple of tips:

Give the enclosure a quick go over again with abrasive just before you are ready to go, just to remove any oxidation.

Wash the enclosure thoroughly with hot soapy water and dry.

De-grease thoroughly with acetone or similar degreaser. Wear gloves to avoid leaving greasy fingerprints. Keep cleaning until no more dirt comes off.

Spray a couple of coats of lacquer and leave to dry, or bake it.

Paint your lettering on. and when dry, shoot as many coats of lacquer over it as you want.

Wear gloves all the while - greasy fingerprints are your enemy!

Don't forget that when the lacquer is nice and hard, you can rub it over with very fine abrasive if you want a matt look to it.

[Travis]

Good advice from Zach and Beaker already

One thing I'd add is that in the past I have thoroughly cleaned an enclosure before finishing, and then dried it with a paper towel which left tiny fibers on the enclosure. The fibers are small enough to be really difficult or impossible to see until you spray the finish, then you will really notice them

So my advice is to really check the enclosure for any fibers after you clean it off. Use a clean rag that doesn't leave fibers behind, or burn the fibers off prior to finishing