Baking Enamel onto Aluminum

[phillip]

I've had a lot of success painting boxes with lacquer paint and not even worrying about it chipping or peeling off because lacquer dries so hard and tough all by itself, but there's a definite lack of different colors in lacquer.  So I was wondering how you guys go about baking enamel paints onto aluminum boxes.  Do I need to apply a primer and bake that on first or just spray the first color coat and go from there?

Let me hear all the different ways, temperatures, and baking times

Phillip

[ian87]

regular old auto primer > enamel > clearcoat > bake at 100-200F for 30 minutes or so.

still chips, tho. :?

[niftydog]

some enamel paints come with directions for baking.  The one's I'm experimenting with at the moment tell you to let it air dry for 1 hour before baking for half an hour.  (I forget the exact temp.)

Etching primer is good, make sure you don't get a "filling" primer, as this will be very thick.  Heating the surface prior to painting can also help with adhesion.

Thorough prep, multiple thin coats and a good clear coat will reduce chipage.  I'm looking at getting a cheap airbrush set up in the near future, I'll keep the group posted on my findings!

If you can justify it, I'm told that automotive two pak is "da'bomb."  You may want to look into that.

[Fret Wire]

I second the etching type primers. A primer specified for aluminum will yield better results. If the primer doesnt bond, the subsequent coats will lift right off with the primer.

[EdJ]

Maybe i can add a little in the spraying department:get a so called banding wheel at a pottery supply or take a broken record player and disconnect the drive string or whatever there is in there to attach the motor to the disk you then can rotate the disk with your left hand having your right hand free for the spraygun.Put the box you want to spray paint on over something it easily fits over yet is heavy enough not to fall over when you turn the wheel/recordplayer.
Something like a foodcan or an upsidedown standing cup will do.Rotate the wheel slowly and spray a few seconds at a time.Keep a close eye on what you are doing and how the paintlayer is building up.Don`t keep the paint nozzle at the same place and don`t hasten the job.Protect your lungs by using an appropriate  dust mask like a 3m ppp.Begin with the bottom plate of your box by placing it upside down over the foodcan when enough paint is applied you can easily lift it from the foodcan.Then place the boxpart of the box over the foodcan.Since you got to practise on the bottom you will have an idea how much you have to spray to get a good coating.
Don`t spray too close or use too much pressure if you do you will notice that you are spaying an orange peel like surface on the box.If you spray from too far away it will take forever to build up a layer.
Furthermore follow the instructions that came with the paint you bought.
If you are much in doubt spray something else before you spray your box.
It takes a little practice off course.
Have fun!
Ed