Using Battery to Anodize

[ard3]

if you use a car battery to power the anodizing, is it necessary to use some kind of resistance to limit the current? possibly an adjustable resistance in order to control the current, if so how many ohms are we talking?

if the circuit consists of
car battery---alum wire---part---acid solution---cathode---alum wire---back to battery
will that generate an overwhelming amount of current? or does the sulfuric acid solution provide enough resistance

[Tim Wiltse]

ard3,

The good thing with anodizing is is that it will only use what it needs for power. If you have a battery that will put out 650 amps and the job piece only needs lets say 3amps to anodize, it will only pull the 3 amps.

Later,
Tim

[Fibergeek]

The good thing with anodizing is is that it will only use what it needs for power. If you have a battery that will put out 650 amps and the job piece only needs lets say 3amps to anodize, it will only pull the 3 amps.

Yeah, but only after it's grown enough of a anodize layer to limit the current, which will take minutes at least. When the anodizing process starts the circuit is practically a dead short.

The origin of the car battery internet old wives tale is probably the British amateur telescope makers. The part that got omitted was that they were using partially discharged motorcycle batteries or junked car batteries. The battery was junked because the plates are shot and it won't put out anything near 650 amps or whatever.

A healthy car battery is dangerous for this without the proper current limiting.