Rust removal with Electrolysis

JLove1974

Twelve Pointer
Recently I was given an old Rockaway type ax head of unknown origin, and I was looking for a way to remove rust so I could find the forge stamping.
I had heard of electrolysis before but I had never used the process, and it's much less intimidating that it looks/sounds.

Basically, electricity flows from negative to positive. If you put two metal objects in an electrolyte (this being a liquid that conducts electrity) then the process of rust forming is reverse on the NEGATIVELY
charged item(s). Basic stuff, 6th grade science. So......here's a thread to discuss. I did not take any before photos of the ax head because I'm short sighted, but here's the process at work

I got a non-conducting tub, filled it with warm water, and dissolved about two tablespoons of baking soda. This is the electrolyte. Then I hooked up my 2/10/55 amp battery chargers leads like this:
The negative cable goes to the item you want to remove rust from. In this case, it was an axe head that had pretty comprehensive surface rust. I wrapped some copper wire around it, and suspended it in the liquid. I hooked the alligator clip to the copper wire at first, then to the metal rod suspending the ax head. It worked the same either way.

The positive connection goes to your sacrificial ANODE aka something that you will throw away. In this case I used a Craftsman lawnmower blade that I no longer own the matching mower for. Star wheel bolts!

I tried various ways to send DC current into the process, but I ended on 55 amp MANUAL START mode. This put about 6 amps of current initially into the process. This really got the soup cooking!

Anyhow, this process needs to take place in a well ventilated area. I used a box fan to blow the HYDROGEN GAS out of the garage, and I didn't plug the charger in until I had all connections made.
You don't want a spark, but this process isn't really any more dangerous than charging a lead acid battery. Wear gloves and goggles if you are worried. I wasn't. Of course I wear flip flops to weld.

[video=youtube_share;xt-sdY2eaSQ]http://youtu.be/xt-sdY2eaSQ[/video]
 

darenative

Twelve Pointer
I've wanted to try this on a bunch of things, but after reading about hydrogen embrittlement, it has me gun shy. The internet is great for general info, but sometimes it's difficult to sort fact from fiction. Anybody know for certain what the chances are for weakening the part you are removing rust from?
 

JLove1974

Twelve Pointer
I've wanted to try this on a bunch of things, but after reading about hydrogen embrittlement, it has me gun shy. The internet is great for general info, but sometimes it's difficult to sort fact from fiction. Anybody know for certain what the chances are for weakening the part you are removing rust from?

hydrogen from electrolysis usually escapes into the atmosphere, and being trapped in the pores of forged steel seems like a VERY remote possibility since it's no longer molten steel (unlike welding).
I also soak mine for a while in a hot toaster oven to drive off moisture, so I assume that the hydrogen would be driven off as well.

Put it like this, if it was a drivetrain part or something like a gun barrel, I'd use gentler methods of rust removal. But for an old axehead? 2 hours of ERR isn't going to affect the steel deeper than the surface rust.
 

JLove1974

Twelve Pointer
This is after about 2 hours. Dark patina just like using vinegar or evaporust.
The eye is still got a little rust but I'm thinking that will help hold the handle in :D
I'm about to order a handle from thehickoryhandlestore.com aka Beaver Tooth Handle Co. in TN.

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JLove1974

Twelve Pointer
Yeah the good thing is the solution doesn't really go bad so you can have a electrolysis vat wired up and read to go, and just change out the solution when it gets really nasty. Make sure you don't smoke like someone suggested!
 
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