Besides what Fibergeek said, you have a couple other options.
For a 1.2 sq/in piece anodized at 3 amps/sq ft = .025amps current setting.
If you anodize at a higher current density, say 6 amps/sq ft, your current setting would be .05 amp current setting. Doing 20 pieces at one time will bring your current setting up to 1.0 amps. If you don't have that many parts to do simultaneously, then put in a sacrificial piece of aluminum.
For instance, in addition to the part you want to anodize, connect up a 2nd piece of sheet aluminum, say 4" x 4" = 32 sq in surface area.
This sacrificial piece, plus the part, would total 33.2 sq in. At 6 amp current density, you would set the current at 1.4 amps. [(33.2 / 144 sq in) * 6 amp current density = 1.38 amps]. If you want or need to anodize at a 3 amp current density, just increase the size of the sacrificial aluminum to 5" x 5". [(51.2" / 144 sq in) * 3 amp current density = 2.13 amps]
Aluminum foil should work as the sacrificial aluminum and could be disposed of after each use. Or, you could use aluminum sheeting or a block/rod of aluminum, but you'd have to strip the anodizing that grows on it after every use.
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