Cathode size

[R-Wells New User Find all posts View Profile Close R-Wells]

Is there a Ideal cathode size.
Using LCD, my tanks size is about 18"x24" , the depth of the electrolyte is about 13" deep, 13 gallons of electrolyte. ( not exact measurments)
My parts range from about 4 sq inches to 400 sq inches.
I am cosidering using aluminum sheet 0.190" thick, one on each end of the tank.

What would be a good cathode size?

Thanks
Rusty

[sswee Metal Finishing Guru Find all posts View Profile Close sswee]

Cathode Size

The rule is a cathode with equal or more SA to the part. Too small a cathode will cause problems. A cathode way oversized doesn't have an adverse effect. My tank is about the same size as yours . I have a lead sheet that runs the length of the tank and down one side, across the bottom and up the opposing side. The parts run have been as small as 6 sq in with no problems.

[acidrain Metal Finishing Guru Find all posts View Profile Close acidrain]

Exactly as sswee says.
I started out using aluminum sheat, but the aluminum turns colors, and I wasn't confident the connections and overall performance of the cathode was the best it could be.
I replaced it with lead sheat and couldn't be happier with the performance of my tank. I suggest lead cathode if you can get it.

[R-Wells New User Find all posts View Profile Close R-Wells]

Hi acidrain,
Where did you find the lead sheets,
How are you conecting to them.
I have been using aluminum sheets for about two years now,
just recently decided to try the LCD method, and was using the lead plates that came with the Caswell kit. but they are not really large enough for my tank.

Thanks
Rusty

[RedRiver Amateur Metal Finisher Find all posts View Profile Close RedRiver]

Re: Cathode size

If I'm not mistaken, lead cathodes pose one problem. Lead leaches out and into the water. Again, if I am not mistaken, lead in the water is something the governement watches rather closely.

Also, I believe that lead cathodes produce more heat than say a 6061T6 cathode would because more voltage is required whenusing lead as a cathode. If heat buildup in your anodizing tank is an issue, aluminum cathodes may be they way to go.

[acidrain Metal Finishing Guru Find all posts View Profile Close acidrain]

Re: Cathode size

Hmmm... old thread, but I'll go ahead and answer anyway.
R-Wells, I purchaced the lead sheat locally at a metals supply house. The sheet is about 1/16in thick, and a piece 4ft.x18in. was around $35.
RedRiver, I saw no rise in volts when changing to lead that would indicate more power requirements. My lead sheet has been in my tank for over a year now, and sill works perfectly, with no indication of lead disappearing into the tank. I had to change the connection bolts once, but that is normal maintanence.
I'm sure the miniscule amounts of lead that go into a home-sized tank are minimal, and not worth worrying about. The bigger worry would be the actual solid lead left over from an abandoned opperation. 10 or 20 lbs of lead would not be a good thing to dump in a land fill, or worse yet, allow to sit in a field somewhere.

[RedRiver Amateur Metal Finisher Find all posts View Profile Close RedRiver]

Re: Cathode size

The bigger worry would be the actual solid lead left over from an abandoned opperation. 10 or 20 lbs of lead would not be a good thing to dump in a land fill, or worse yet, allow to sit in a field somewhere.

I agree. Dispose of waste accordingly. Also note, that just because you can't see lead in the solution, doesn't mean that it is not present...

Fruit for thought...Hazardous waste is hazardous regardless of the quantity!

[destroyer125 Experienced Metal Finisher Find all posts View Profile Close destroyer125]

Re: Cathode size

my cathode I made myself with the electric eye i use to heat my sealing pot....a coffee can...a few lead bars..and an old cookie sheet...used cookie sheet as a mold