Just thought I'd share this for those who want to try their hand at anodizing their flashlight at home without using sulfuric acid. Pulled from one of my favorite websites... Hack-a-Day.... Hope this helps someone... I think I'll give it a go as well... Nutz
Here's the Hack-a-Day link as well... credit where credit is due...
Its the same process, using a very slightly different chemical, that when mixed with water makes an acid as well. Either way you're using acid and disposal is an issue in the concentrations being used.
As a note if you want good even coverage you need agitation of the solution, and you should make sure not to boil it on the surface of the part through over driving the current.
Chilling the solution to between 0 and 4 deg C will let you run it longer and make HAIII. Which is inherently dark grey to black, due to the small pore size and thickness.
But for HA3 you also need more careful current voltage and current control as far as I remember. You probably need quite a lot of far from cheap process control gear to do this.
Depends, if you're doing a couple (small) parts, not really, a simple CC/CV power supply will do it. I did semi-production parts this way for a couple years in my garage. Winter in an unheated garage kept the stuff cold for part of the year, the summer I ran it in a chest freezer.
The big thing is making sure you don't breathe the mist/fumes from agitation while running it.