Electrolytic Rust Removal

[Iplayfarmer]

Due in large part to comments and suggestions here, I have decided to try my hand at electrolytic rust removal. I have a pair of cast iron kettles that I bought the other day at a yard sale. I got them to match my antique wood fired cook stove that I am planning to put in my little shop after it is built. The kettles have a lot of rust in them. I buffed the outside a bit, but I just can't get to the inside with any that will efficiently take the rust and scale off. The inside is what matters most because I'd like to be comfortable drinking the water that comes out of these kettles. So, I have decided to try my hand at removing the rust by electrolysis.

I've posted a before picture of the first kettle. I wish I would have taken a picture before I started buffing the rust off the outside. It was pretty bad. I have the kettle suspended in about 4 gallons of water and 1/2 cup of Arm and Hammer washing soda. I have a 1/16" plate of steel bent to fit the countour of the bucket, and the positive terminal of a 6 amp 12 volt charger is connected to this plate. The negative terminal is connected directly to the kettle. I left this concoction to stew for about 3 hours and checked it. The water was very murky, but the pot hadn't changed much. I changed the water and started again. The second picture is the second batch of water after about an hour. I'm going to let it stew overnight and I'll check it in the morning.

[crash325]

Please keep posting your progress. I have a lot stuff to de-rust.
Good luck & have Fun.

[DJ54]

I've had good luck with the couple of times I tried it. I used a 10 amp charger, and water was bubbling within a couple of minutes. I found best results were attained after 24 hrs.

I did some horseshoes the first time, then a David Bradley planter frame in a 35 gal. plastic trash can. It even loosened most of what was left of the old paint. Best to hose off, and clean right away. A Scotch Brite pad may be the answer to cleaning the inside.

In the link I found on it, it said you could clean items internally, by using an internal anode. Just have to watch about it contacting the sides.

This is what heppens if it does... oops...

[Stick895]

I have seen over on hotrodding forums where molassass can be used for rust removal. Maybe try that for the other kettle?

[k0ua]

I would suggest for better results, to have a clean anode, nice shiny steel and suspend the anode in the center of the kettle with the anode sticking up out of the solution where you will attach the + terminal. Since you are mostly concerned about the inside of the kettle, you will have better results with the anode inside of the kettle.

James K0UA

[DJ54]

Just don't use stainless steel... I thought I had the perfect way to utilize some submersdible pump jackets, but it is a no-no. Produces a toxic gas, of which the name escapes me at the moment...

[Soundguy]

quit dumping your water.. it's a waste.

and as the other poster said.

if the rust is on the inside.. put the anode on the inside.

won't do any good on the outside!

it's line of site!

[Iplayfarmer]

I looked again this morning, and there is some progress on the outside of the kettle, but very little on the inside. I changed the water again (that was before I read the words of wisdom from Soundguy), and rigged a system to have an anode on the inside of the kettle. I'll leave it for the day while I'm at work and see how it looks.

Does temperature have anything to do with the rate of the process? It got pretty cold overnight.

[tcartwri]

Buddy of mine has a large tank that he does this in.... It takes probably a week to remove the level of scale you are showing.

[DJ54]

Seems one of the threads I read on it, warm temps did seem to work better. By the time I got around to doing mine, it was in the low 70's, so don't really know.

Another no-no... Do not do it inside, as the process produces hydrogen gas. Just think..., "Remember the Hindenberg"