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Stripping One Color and Re-Anodizing Another on Aluminum

Hello All,

When I was a teenager, we used to strip anodized BMX bike parts with Easy-Off oven cleaner [on eBay or Amazon]. Now that I'm a 36 year old kid, I want to strip my purple aluminum R/C car parts and re-anodize them any color I want. The pieces in question are 6061-T6 with one 7075 piece of unknown hardness.

Will the fact that they have been previously anodized affect the process? Is Easy-off my best bet, or is there something more effective and just as safe? Even though I am doing this in my garage, I do have some safety equipment set up (rubber garments, eye and face protection, fume respirator, and eyewash station). I also have an old fry hood from a restaurant job I did. It is 3'x 3' and all stainless. Is this suitable for acid fumes? It moves 2500 cfm according to the plate on the side. I am in a very residential setting, so I need to keep the toxic waste to a minimum.

This leads to another question. Can I totally neutralize the acid bath so it can be disposed of normally? As far as dyes go, what is recommended?

And finally, can anyone suggest any good books on the subject?

Thanks in advance,

Chris Gagnon
- Fredericksburg, Virginia, USA
2001

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Use a chemical etch with sodium hydroxide. You can use that to strip the old color and anodizing to a certain degree, but be very careful with the parts and the chemicals, this will burn the parts and any part of your body! Have your local job shop look into it if you're going to re-anodize it anyway, it might be cheaper and far less of a headache.

Josh Sonju
Sonju Idustrial Inc. - Kalispell, Montana, USA
2001