Another electrolysis question

[Mike(NEOhio)]

I've been doing a few parts in recent weeks. Started out with a piece of 1/8 x 1 steel for the anode and it usually ran about 2 amps I had to clean the goop off every couple of hours as the amps dropped to near zero. Figured surface area might have a lot to do with the process. I bent up a 1/2 inch rod to hang across the tub and got nearly 10 amps, for an hour or two, then down to 3-5 then zero. The black goop collects on the anode very quickly. I just guessed at mixing the solution and probably got way more soda than was needed. Would that make a difference? How often should the solution be changed? The parts are left with a black coating like the anode.

 

[JoeM(GA)]

A tablespoon per gallon is plenty. The black on your part is part of the result of the rust removal chemical reaction, it can be quickly be removed with water and a scotch brite pad or a soft stainless ste3l brush. Flash rust will form quickly, you’ll need to treat it quickly. Surface area is very important to keep things going, remember this is a line of sight process, you might have to rotate the part or move the anode(s)

 

[Fixingfarmer]

3 or 4 inch Wide flat 3/16 piece of strap that sticks out of the water enough to put the alligator clips on seems to work for me as the sacrificial positive annode you should be able to leave it overnight

As it gets covered it will collect all the way across the plate as long as it’s flat or close to flat