[9W Monighan]

When I need to have some of my aluminum refinished I take it to the anodizer and they dip the metal into caustic soda to strip the old color off. Pretty cool to watch but if it's left too long the caustic will erode all the metal away. I can't remember but I think it turns black, then it's dipped into sulfuric acid and it brightens up. All of the anodized parts used on this hobby stuff is not sealed with the nickel solution like architectural metal to keep the color from fading from sunlight. So hobby items would strip very easily with the chemicals everybody has mentioned.