Also posted on FB: Trying to learn to anodize aluminum because.......it's more expensive and slows down the building process?
Anyway, had mixed results and are figuring out what went wrong, etc. Mistakes: 1. Used battery acid, which is OK, but we don't know the exact mix and assumed it was 37%, which when cut 50/50 should put it in the range required.(10% to 20%) But we think it is stronger than 37%. because it really drew a lot of power and caused a lot of gassing. (We think this is part of the reason the coloration was so varied and it also causes poor anodization because the microscopic bubbles keep the solution away from the metal) 2: We used .032" safety wire to hang parts. BIG NO NO. Stainless contaminated the mix, (Orangey color), and the wires only lasted 40 minutes before being eaten in half. Use only aluminum or titanium wire. 3: the cathode, (1/4" rods in the tank) should have more total area than the parts being anodized. we weren't even close. Still looking for some sheet lead, so if you have any ideas...... 4: Keep parts in the bath for the proper time. We thought 40 minutes might be enough, (Not much choice since thats the the wires broke), but with 16 pieces in the tank time should have probably been in the neighborhood of 80 minutes. 5: Don't allow pieces to touch in the dye tank. They will be darker where they touch, lighter where they don't. They should hang suspended and not touching anything. Trying again with smaller batches and application of new knowledge. Still researching and finding better ways, but if you've done this sort of thing before and can shed a little light on the process please sound off. Eagle on!
