RUST!!! Removal. Using Electrolysis.




If you're going to own metal objects you "will" have to deal with RUST!!!

In this project I will use electrolysis to remove the rust from my much neglected Dog N' Brat Cooker.

These are wonderful tools. They're made for campfire use.

You put food in, stick them into the coals for a while then open, revealing a delicious treat.

The problem is, people forget them beside the fire when they retire for the night.

Obviously, mine has been neglected for quite some time.

I will show you how to bring this sad looking item back to it's former glory.

This is also a bit of an experiment using two different energy sources.

I'm curious if one will do a better job than the other.


One nasty looking rusty item. In this case a Dog N' Brat Cooker.

A battery charger

A computer power supply

Two pieces of electrical wire

Two alligator clamps

Two pails

Water to fill the pails

PH+ from your local pool supply store

Some scrap iron. I used a piece of flat bar I had lying around in my barn

DO NOT USE STAINLESS STEEL!!! as the sacrificial scrap it creates toxins in the water and poison gasses

Conductive wire. I used some extra electric fence wire I had in the barn.

8 threaded screws or bolts again found in the barn.

A drill bit and tap the same thread as the screws

A drill press or hand drill

A bench grinder

A hand grinder

A roll of electrical

A scrub brush

Cooking oil

A table to work on in a protected well ventilated area. In my case an overhang beside my barn.

I think that's all.

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Step 1: The Battery Charger

The battery charger has to have a manual switch. I found this one at a thrift shop for $19.99. I thought that was a good price so I scooped it up. If you can't find a manual charger, you would need a 12v automobile battery and booster cables. An automatic charger would power down if no battery was present. A manual one will pump out 12 volts regardless.

Step 2: The Computer Power Supply

The picture with the price of $2.99 was from the same thrift shop as the battery charger. I had my own already from a previous project. I just snapped the pic to use in this Instructable to show how you could source one. We will draw the 12 volts required for this project from this cheap source.

Step 3: Process the Power Supply.

To set up the power supply ,cut off all the plugs. If there are any plastic zip ties holding the wires together ,remove them as well.Then open the metal box by removing the 4 screws that hold it closed. Now release the wires from the metal box. To do this, slide the plastic protector that holds them open and lift all the wires free. Now collect each color and group them together. As you can see in the picture above, each color is labeled on the control board. There are 3.3v, 12v, 5v and GND wires. A few others that we won't bother with. We will be using the single green wire. Collect the orange 3.3v the yellow 12v the red 5v and the black GND wires and put them back into the plastic holder so that they will again exit the enclosure.

Step 4: Connect the Ground Wire to the Power Supply Box.

As you can see in the first pic, the green wire is labeled PS/On. This wire would have been connected to the computers front power button. In pic number two you see where we want to connect it. This will make the control board believe that the power switch has been turned on. If your power supply has a main power switch, it will now turn on as soon as you turn the switch on. If there is no main power switch on the power supply, it will now turn on whenever you plug it in to an electrical outlet.

Step 5: Collect the Left Over Wires

There are a few other wires that we won't be using. Wrap the ends and tie them out of the way. Don't rest them on the cooling fins just to be safe.

Step 6: Time to Close

Now close the box, being careful not to catch any wires in the seams. With your electrical tape ,wrap the same colored wires together into a cord. I split the GRD wires into two bundles. There were twice as many of them as there were each of the other colors. I did this so that, in the future if I want to do two things at the same time with the power supply, I will have two GRD sources to work with. I also connected a longer wire with an alligator clamp to the 12v and one of the GND wires. The 5v and 3.3v are just wrapped for later use. I have written the colors and matching voltages on the supply for future reference.That's the end of creating the power supply.

Step 7: The Water

Water isn't a great conductor of electricity so it needs some help. To become an electrolyte solution something must be added to it. I have chosen PH+ because its cheap and easily sourced. I've added 2tbsp of the powder to approximately 2 gallons of water. Each of the pails have an equal mix.

Step 8: Create the Sacrificial Iron Pieces

Electrolysis involves electrical charge traveling from one piece of iron to another through an electrolyte solution. When this happens, one piece of iron is sacrificed to help repair the other. We are now going to create the sacrificial pieces to put into our electrolyte solution. So measure the height of the pails and add an inch for an area to create connection points. In this case we need 12" pieces. Do not use stainless steel for this it causes toxins in the water and poison gasses.


You can use a chop saw like this, a hack saw or, use other items that don't need to be cut. Concrete reinforcement rods ,commonly called rebar, work well. As stated previously don't use stainless steel. Electrolysis is a line of sight process so I'm using a piece of sacrificial iron on the 4 sides of each pail.

Step 10: Clean Up a Bit

My sacrificial iron is pretty rusty so I'll grind it a bit. I won't subject you to another noisy video. This will be loud as well. Hearing and eye protection are suggested.

Step 11: Take Off Sharp Edges

The items being created will all be kept for future use so I'm making them less dangerous. The chop saw leaves very sharp edges. A few minutes spent grinding them off is time well spent.

Step 12: The Bolts

These round head bolts were left over from a tin shed I built over 10 years ago. They were collecting dust in the barn since that project was complete. I have no idea what size and thread they are. In my tap and die set there is a tool for that. A chart is also included that tells me what drill size to use when drilling a hole for this size tap.

Step 13: Drill and Tap Holes

If you don't have this equipment, use longer bolts with nuts and drill larger holes. If using rebar ,you can connect the pieces with wire and hose clamps.

Step 14: Check the Fit

A piece of the wire I'm using fits nicely so I'll continue with the rest of the holes.

Step 15: Wire Up the Sacraficial Iron

The wire I'm using is left over electric fence wire. It hangs in the barn and gets used for all kinds of projects. As I wire these pieces together, I'm also using the wire to hold the bars in place. I don't want them drifting around the pail. The sacrificial iron and the rusted item being cleaned must not touch each other!

Step 16: All Items Are Ready

The two halves of the dog n' brat cooker are as equal of items as I can find for the side by side comparison of the two power sources.

Step 17: Hook Em' Up

I've used a piece of an old skid to prop the halves of the cooker up in the pails. The positive 12v wires are connected to the sacrificial iron which are all connected to each other. The GND wires are connected just outside of view at the top of the picture. They are clamped to the cookers long metal arms.

Step 18: Turn the Power On

OK were ready to start the procedure. With the power turned on now, I'll see if enough PH+ has been added to allow current to pass through the electrolyte solution. As you can see in the video, each of the setups are bubbling nicely. No additional PH+ will be required.

Step 19: Two Hours Later

Two hours have passed since we turned the power on. As seen in the video, they both appear to be working equally well. I'll see tomorrow morning if the pieces are both clean.

Step 20: Just a Quick Pic of Both.

Its really is hard to see a difference. Without seeing the clamps on the sacrificial iron, they would appear identical.I've checked all the wires and connections for heat build up. Everything feels fine so I'm confident that I can leave them going over night.

Step 21: Good Morning

Its morning, 16 hours has passed since I flipped on the power. All wires are cool to the touch. There isn't as much sludge on top of the electrolyte now.

Step 22: 16 Hrs Video

Here's a video of the tanks in the morning, still bubbling nicely. Time to shut things down and see how the cooker looks.

Step 23: Elbow Grease Is Needed

A little scrubbing is required. Very little actually.

Step 24: Pretty Clean

They look nice wet. Don't they?

Step 25: A Comparison

A side by side dry comparison tells the tale. The computer power supply side left the piece with slightly more rust residue. I put them back in for another two hrs after cleaning them.

Step 26: Two Hrs Later

Two hours later, I'm happy with the result.

Step 27: Soap and Water Cleaning

Now into the house for a soap and water scrub down and a coat of grape seed oil

Step 28: Just Like New

Wow, what a difference. I wouldn't hesitate to offer someone food cooked in this. In fact, the nights are getting cooler here in southern Ontario. The fire pit beckons. I will have to heed the call.

As for the experiment portion of this Instructable ,my conclusion is that, a battery charger will do a slightly better job than a computer power supply. When given equal time to complete the job. Both power sources will do the job. A computer power supply gives you other voltage options to play with later.

I hope you enjoyed this Instructable.

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    31 Discussions


    Question 11 days ago

    Just what I need but you have not mentioned current what amperage's are you using and does it effect it using more or less I have a variable bench power supply that I can change voltage and amperage

    1 answer

    Reply 11 days ago

    The battery charger was switched to the 10 amp setting and the power supply puts out 25 amps when the +12v wires are used. You can see in the first picture of the supply the voltage and amperage combinations of each output available.
    As was discussed in a previous comment by nonobadog a few days ago, the charger puts out more voltage and so it worked slightly faster. With the amperage of the power supply being more than double that of the charger I suspect it doesn't have much effect. Or it could also be that the extra amperage gave the power supply an extra boost. Without the extra boost maybe the power supply wouldn't have performed quite as well as it did. I'll have to leave the Dog N' Brat cooker out in the rain for a few more years so I can repeat the test with the charger set to 2 amps ;-)
    You mentioned that this is just what you need, so you must have a rusty item to clean. If you set your bench power supply to 12v and 25a you would be using the same setting that my supply used to get the result shown.
    Enjoy your project. I would like to see the before and after shots. Even better an Instructable of your endeavor.


    14 days ago

    It should be mentioned to not use stainless steel as the anode (the sacrificial metal). The chromium in it pollutes the solution with hexavalent chromium, which is extremely toxic and illegal to dump anywhere, it has to be brought to a toxic waste disposal site. If the solution turns yellow, it's because of hex chromium.

    You can clean stainless steel with electrolysis, hex chromium is a result of the oxidation of the anode, the cathode is safe.

    Stainless is usually chosen because it lasts much longer than other metals. I use carbon rods, I've been using the same rods for years and they are still in near new condition.

    3 replies

    Reply 14 days ago

    I have added a few warnings to not use stainless.
    My instructions didn't suggest using it but the warning not to is a good idea. Thanks.
    Where would one source out carbon rods? I keep my iron bars clean by reversing the wires when I'm done and clamping a piece of real scrap to the positive. In this case an old lawn mower blade.


    Reply 14 days ago

    I bought carbon gouging electrodes from McMaster-Carr


    Reply 13 days ago

    Great idea thanks. In my foundry days the welding guys would use these by the thousands to repair the shakers that would remove sand from the castings. There weekend work was gouge and fill. A dirty hot and nasty job to say the least.


    14 days ago

    could you make some comments about the use of 5 volts and 3,3 volts. tks

    5 replies

    Reply 14 days ago

    I'm not sure what to tell you. The supply had these voltages available I felt it wise to leave them available for unknown future projects. I know that 5v is the part of the supply that runs the USB devices. The 3.3v wires were ones I didn't check before removing the supply so I don't know off hand what they do.
    If you have a more delicate piece to process you could use the lesser voltages to slow the process down.
    This gentleman made a comment on another Instructable about lowering voltage when etching with electrolysis. He uses an adjustable bench power supply that has a knob to adjust voltage. You may find that Instructable interesting.


    Reply 14 days ago

    Another thing to keep in mind is that these wires can be combined to give you many more voltages than the standard 3.3, 5, and 12 volts
    Instead of using the black wires as ground, use the lower of any combination of two wires... For example, negative on red wire (5v) and positive on yellow wire (12v) will give you 7 volts... The difference between the two voltages! Using the negative voltage wires (-5v White, -12v Blue) you stashed away will give you even more choices!
    There are many instructables on making a bench power supply from a computer PSU. Pretty handy for testing car audio equipment, led lights, other small projects.


    Reply 14 days ago

    I'm going to have to take a look at some of those bench supply Instructables.
    Mine would look much nicer built up as a proper piece of equipment.


    14 days ago

    Just a quick note, in case anyone wants to skip a few steps and/or keep their PSU at least partially intact for other projects. Instead of cutting off all the plugs & opening the case, you can also just grab the big 20/24-pin plug and jumper the green (PS_ON) pin to any of the black (GND) pins using any random bit of wire that'll stay in place (snipping the wires, stripping the ends, and twisting them together outside the case will also work - if keeping things intact isn't a concern - as will buying/making one of these gadgets: ). PS_ON is just a signal-level connection, so even a bent paperclip is safe, as long as you're careful that it only jumpers green to black.

    Also, if you are cutting off plugs, keep an eye on the purple (5VSB) wire. It's live (usually just a couple amps @ 5VDC, granted... but live) any time the PSU is plugged in (and, if it has a manual switch, switched on) even when it doesn't show any other signs of being running.

    (and thanks for the I'ble... this is something I've been meaning to try out for some time)

    1 reply

    Reply 13 days ago

    Don't skip this step. Unplug the computer before opening it!


    14 days ago

    Just want to summarize my experiences.

    Only use Sodium carbonate, Na2CO3 (also known as washing soda, soda ash and soda crystals), never use Sodium hydroxide.

    Use max 6 volts, higher voltage is not helpful.

    Never use stainless steel, it will cause toxins.

    1 reply

    Reply 14 days ago

    I have added a stainless steel warning. I didn't suggest using it but warning people not to is a good idea. Thank you for the input.


    Question 14 days ago

    I find myself wondering why the charger would do better than the computer PSU...
    Most battery chargers cannot provide as much current as the PSU, so why is it working better? Any ideas?
    Thanks for sharing! ;-)

    3 answers

    Answer 14 days ago

    I will totally plagiarize nonobadog who just commented on that exact question.
    For the power source comparison, the PC power supply puts out a pretty
    well regulated 12 volts while the car battery charger puts out roughly
    13.5 to 14.5 volts. The battery charger should be a little bit faster
    is all.


    Reply 14 days ago

    Thank you both!
    That makes perfect sense. ...I need more coffee. :-)


    Reply 14 days ago

    Maybe you could do an Instructable on brewing the perfect cup of that coffee.