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geekhack Projects => Making Stuff Together! => Topic started by: mike-y on Mon, 05 March 2018, 16:08:53
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Has anyone successfully painted an anodized aluminum case? From one source, I've read that you can't do this at all without first removing the anodizing, and from another source, I'm reading that you can paint it as long as you remove the clear sealant layer first.
I've got a black anodized aluminum case that I'd like to freshen up on the cheap with spray paint of some sort, but I don't want to ruin it by using the incorrect method.
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Sand it all down with 1000 wet sand paper so the paint will stick and not flake.
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You could also get it cerakoted which is a lot nicer
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You can paint over the anodizing, it won't stick well, but you can.
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Primer for aluminium won't work better than any other type of primer would on anodised aluminium .
To adhere really well, it would require a bare raw aluminium surface and preferably one that has been sanded or sandblasted within the last few minutes. The last part is because bare aluminium oxidises in air.
If your case had been sandblasted before being anodised then that should help with paint adhesion.
If you have an airbrush then you could use two-part epoxy paint - which should adhere the best.
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Interesting problem.
http://www.practicalmachinist.com/vb/general/paint-adhesion-anodized-aluminum-157007/
https://www.finishing.com/2000-2199/2102.shtml
tl;dr:
- anodising is a very good base for paints.
- adhesion may depend on the chemical composition of the anodizing solution.
- sealing of the anodised surface will cause lack of adhesion in paint. Also contaminants in the anodising solution may cause that. Use etching solution to remove both (suggested above is a strong base).
- perform usual degreasing procedures. Might want to do that prior to etching. Some inert oil contaminants may not get removed with the base I think, or react forming residue, but don't hold my word for it, I'm no chemist.
Practical Machinist link above also suggests using epoxy based paints/primers.
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Thanks for the information guys. The links from the post above are especially helpful.
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There is actually a special paint that is designed for aluminum. Try asking at hardware stores, and you most probably will find the product I’m talking about. Even if the surfaces are rough or uneven, the paint works perfectly. When I moved to my new house, I was looking for interior painting services singapore (https://www.paintingservicesingapore.sg/), and found out a lot of insightful information about painting in general. Later on, when the guys came to paint the exterior of my house, I also noticed that they had this type of painting with them. They ended up using it for some few areas.
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Use the special type of paint. Aluminium is a little bit difficult to paint.