At 08:58 PM 13/12/2007 -0800, Andrew Gillis wrote:
> I recall that Easy Off oven cleaner has lye in it, and used to work very
well (very !! quickly) in removing anodizing.
>
> However, the last time I used it, there was an additional
(anti-corrosive?) ingredient added, which really slowed the anodizing
removal down to a crawl.
>
> I think that drain cleaner may do the same stripping job. Again, check
the ingredients, and first try it on something non-critical.
>
You never know what "secret ingredients" are in those commercial products. Over the years they've become "safer" but less effective. The drain cleaners have metal particles in them to make them fizz for effect, but who knows if that's actually useful. I've bought lye at the grocery store and used it to etch aluminum for painting and remove aluminum pickup from iron cylinder bores. Never tried lye for removing anodizing, but if it eats through aluminum faster than the anodizing, you could end up with patchy results if you're not careful. Certainly polishing would be needed to finish the job. And remember that once the anodizing is gone, the surface is softer and prone to oxidation and will need repolishing from time to time.
John Betmanis
Woodstock, Ontario
Canada