The Electrolysis Tank, the Tool for Tool Restoration

Rust! Anyone who has been doing metalwork or anything with metal tools has run into this problem. An electrolysis tank uses electrical current to remove rust from your piece of metal or metal tools, that you want to use but has become rusty, corroded, and pretty much unusable. This means that those old adjustable wrenches, tin snips, pliers, garden shears, and any other tool that was seized and ready to be thrown in the scrap bin might have some life in it yet!

A handy feature of this project is the amount of customization that can be used. It can be made small with a 1-2 gallon bucket. It can be made with a 50-gallon drum. There was even one online source that mentioned someone using a 270-gallon livestock watering tank! So if you have some rusty metal to clean up this might be something you may want to try.

This Instructable features the methods I used, but feel free to customize them to your needs.

Materials & Tools

5 Gallon Plastic Bucket (with lid) - https://www.canadiantire.ca/en/pdp/canadian-tire-plastic-food-grade-safe-bucket-5-gal-19-l-0581060p.html

Uninsulated Wire - https://www.canadiantire.ca/en/pdp/hillman-18-gauge-copper-hobby-wire-25-ft-1619089p.html#plp

Screw Hook

Small Scrap of Wood

Pliers and Wire cutters

Drill and drill bits

A battery charger with manual setting options (automatic likely will not work)

In addition, for the electrolysis process you will need:

Item to be cleaned

A piece of sacrificial metal to attract the rust. ( You will eventually end up throwing this away so don't use something of value)

Water

Washing Soda (I used Arm & Hammer brand)

WD 40 or other oil

Drill 5 small holes in the center of the lid as shown in the photos. These holes should be just bigger than the wire that will be used to suspend your item in the tank. The middle hole will be used to thread a hook through to hang items lower in the bucket. The other 4 give the options of hanging multiple items or hanging a larger item from several points. You could also use a metal basket to hold several small items.

Then drill a larger 1 1/2 - 2 inch hole near the edge

This is where you will have your sacrificial metal. The larger hole gives the option to use a longer pipe or rebar that you can clamp the power supply directly to.

For this next step, you will need a scrap piece of wood about 1 inch wide and 3-4 inches long and your screw hook

Drill a hole in the center of the board a little smaller than the threads of the screw hook. Thread the hook from the bottom side of the lid and through the wood that the end of the threads stick up through the top. ( You will connect the power clamp to those threads so keep them there.)

Fill the pail with enough water that it will cover the item you will be hanging in the solution to get cleaned. I used about 2 gallons for the wrench. Then add 1-2 tablespoons of washing soda per gallon of water and stir it to dissolve it in the water.

Cut a piece of wire and attach one end to the hook. Attach the other end to the item you will be cleaning. For this example, an old wrench was used.

Note: Something to keep in mind is that you need to have a good connection so there is a good current flow. If the item is very rusty like this use a wire brush to clean down a small area where you wrap the wire around down to clean the metal. This will almost guarantee better success.

If using a longer piece of scrap metal like a pipe or rebar place it in the pail with the other end sticking out the hole in the lid we drilled earlier. You could also use a wire to extend down into the liquid as well.

Both pieces should be in contact with the solution but should NOT touch each other. Otherwise the current will cause a short.

Fasten the lid securely onto the pail.

NUMBER ONE of this step!! Make sure your charger is turned off and even better yet unplugged.

Attach the positive clamp to the sacrificial piece of metal being used. Attach the negative to the screw hook from which the piece being cleaned is hung.

This next step is usually where the great debate begins. What amperage should be used?

Again, what I used is what works for me and is not the only way. A lot of online sources may tell you differently and I'm sure some will comment so as well.

My charger has two settings on the low setting. 2 amps and 20 amps. I could not get it to work on 2 amps although that is what the majority of sources will tell you to use. The lower the better so to speak. I used it on 20 and have had decent success with that. You may want to experiment with that to find what works for you.

Note: Also make sure it's on a manual setting for voltage and time otherwise it may shut off before complete.

Once the charger is running you will begin to see bubbles coming up. Over the next few hours, rust will begin to float and also move from the piece being cleaned to the sacrificial piece. In simple scientific terms, the positive attracts the negative rust and it goes on to the positively charged piece.

How long will the process take? This depends on the size being cleaned and the amount of rust. This will take from a few hours to 2-3 days.

Several things to keep in mind. So for this project, I used a round pipe for the sacrificial piece of metal. This worked ok but needed to be cleaned various times every couple of hours or the process slowed down. So it may be better to choose a piece that has a large flat surface area such as an old saw blade. Some users recommend several pieces surrounding the outside perimeter of the tank.

Also, do this in a well-ventilated area or outside as the gas produced is hydrogen and is explosive.

When the piece is finished, most of the rust should be removed. There will be a bit of black coating which we will take care of in the next step.

To get rid of the last bit of rust and some of the extra black residue clean with a wire brush. When the process is complete spray a light coat of WD-40 or something of a protective nature to keep surface rust almost immediately appear. These two pictures compare the before and after brushing so that the last bit of effort can clean up and enhances the quality of your piece.

There you have it. The process that will save a lot of those tools you thought was scrap.

Please be sure to follow all safety precautions when using this as it is using electricity and can be dangerous if misused.

Please feel free to leave comments or questions and any suggestions for improvements that you may have.