Anodizing - has anyone tried it at home?

[sanddrag]

Has anyone tried doing aniodizing at home? Doesn't seem like an incredibly complicated or expensive process. From what I read, all you need is some battery acid, distilled water, some electric current, some fabric dye, and some boiling water.

Has anyone tried it? How were the results?

[Andrew Blair]

229?

[dtengineering]

We've tried it with small items. It works well enough, I suppose, but we still haven't figured out the best way to make the electrical connection to the part being anodized. Often the connection itself will anodize first, cutting off the current flow to the part.

When it does work, though, the results are most impressive. It's not hard, just be safe working with the acid.

Jason

[sanddrag]

What did you use for the current and where did you get the acid? Do you have any pictures?

[Pat Fairbank]

It works well enough, I suppose, but we still haven't figured out the best way to make the electrical connection to the part being anodized. Often the connection itself will anodize first, cutting off the current flow to the part.
I've found that drilling a hole, tapping it, and screwing in some aluminium wire works well.

What did you use for the current and where did you get the acid?
When 296 tried homebrew anodizing last year, we used a really big 12V manual battery charger that put out about 40 amps. The acid was ordered for us through the school's chemistry dept.

I wrote a post here (http://www.chiefdelphi.com/forums/showthread.php?p=330136#post33013) describing our process - it's far from being perfect, but the general idea is there. I'm anxiously awaiting 229's whitepaper, and hoping to get some tips from it to improve our own process.

[Tim Delles]

Yes we have done our on home anodizing this year with some of the parts on our robot. Our head machinist who was did most of the anodizing for the team is still getting all of the documentation together. It will be up on our website (team229.org) as soon as he gets it all together.