Rust Electrolysis Tank Setup, ver. 2.0
Not trying to re-invent the wheel, but a better mouse trap here. In my case, an electrolysis tank that suites my needs, knock downs easily, quick cleanup and either upgradable or down gradable.
I won't get into what is an electrolysis tank and how it works. Many of you know what it does and some of the science behind it. However, for those that want additional reading as to what and how, here are two sites I found interesting:
This site gives you what is an electrolysis tank and basic how it works. The author basically uses a five gallon bucket with some metal as anodes. Nothing fancy, like many here who use what ever is around.
Rust Electrolysis | David J. Kelly Woodcrafts
The second link is a bit more detailed and technical, but interesting. The author gives you step by step on how to construct one and the supplies needed for cleaning the parts afterwards.
Rust Removal Using Electrolysis
My method is just anodes that hooks/hangs onto the side of the container. Easily pulls out for maintenance, cleaning and storage.
1- THE CONTAINER:
You will see a 5 gallon bucket on the center with markings for each gallon of water. This was my first electrolysis tank using some old 3/4" diameter steel stakes I had laying around. The stakes were twice as tall as the bucket and no means of keeping them from moving around. Well, you could use spring clamps, but I didn't. I now use this smaller bucket to measure the water going into the larger one and that way I know how much baking soda to add per gallon.
The current setup uses a 20 gallon commercial grade trash container. The one to the left is a similar larger 32 gallon one. These can be purchased at any home improvement big box store. Depending what your needs are and what size parts you are putting in, you can use what ever size container you want. The rebar anodes will be cut to match the height of the container being used. More on that later. Try not to use regular storage containers or household plastic trash cans. These have thin plastic walls and can blow out on you if you fill it to capacity. The above gray containers are heavy duty with thicker walls. Plastic 55 gallon drums work perfectly and easily available used. I have one of these and will make another setup for much larger parts, like with my 1942 Delta Unisaw cabinet saw.
I my case I purchased a 10' piece of 5/8" diameter(#5) rebar. The 20 gallon container is roughly 24" tall so I cut the rebar into five equal parts, 24" each. I had a 2' length of 3/4" steel stake around that was used as the cross piece to hang the parts from in the water. If you don't have something thick and strong for this cross piece you can purchase more rebar.
If using a large container like here, cut five rebar's. This will give more surface area for the electrolysis to work and more "line of sight" coverage for the rust to travel to. This way you won't have to rotate the part that is being clean.
The Hook was made from some 1/4 steel stock also laying around. You want the anodes to stay at least a 1/2" above the bottom of the container, this way they're hanging freely on the edge of the container. Mark the point on the rebar where it meets the top edge of the container. This is were you will weld the L shaped hook.
Weld one L shape hook on each of the anodes. Then weld a 1-1/2" long bolt to the vertical part of the L shape hook. This bolt is where the positive lead wire and positive clamp from the battery charger will go.
Next, install a nut tight up against the head of the bolt, followed by two washers, and another nut. In between the washers is were the positive lead wire will be tighten to.
3-POSITIVE LEAD WIRE:
At first, the 5 gallon and 20 gallon setup both used a 14ga copper wire. When I decided to post this build and rebuild it for the photos I decided to switch to 10ga copper wire for two reasons. First, thicker wire for more conductivity and second, it's stiffer and more manageable than the thinner 14ga. Because of this it will hold it shape around the container and keep the anodes from moving.
For this setup, I cut an 80" piece of 10ga wire. Measure the circumference/perimeter of the container and add about 20-24" to that measurement for the wire. This will give you more room for the loop bends around each anode. My suggestions is to use insulated wire, not bare. If bare, you may accidentally come in contact with it while positioning the Negative battery charger clamp.
What ever measurement you come up with divide it by the number of anodes made. In my case 5 anodes divided by 80" = 16" spacing along the wire. At each mark, remove a 2" section of insulation and also at each end. Bend the wire into a circle.
Next is making the u-shape loop at each stripped point on the wire. You can either use the bolt on the anode as a guide or a pair of needle-nose pliers. Don't crimp the wire together. You want to able, with 1-2 turns of the outside nut, just lift the wire for any maintenance, cleanup or storage.
Make sure the loops are all facing up. It should look like this when done.
Install the anodes spaced evenly around the inside of the container. Then carefully drop the positive lead wire onto the anode hooks. Then one by one install the stripped copper loop in between the washers and tighten the outside nut. The good thing about the heavier gauge wire is that it will evenly space the anodes. No need for clamps, since the hooks and wire will hold it in its place.
Finally, another rebar going across the top to hang your parts from and to clamp the Negative from the battery charger at either end. Since I used up the 10' length of rebar to make the anodes, I did have a 2' by 3/4" diameter stake at hand for this purpose. Just make sure it's clean throughout for better electrical conductivity and not touching the anodes.
Remember the Positive(red) clamp goes to the anodes and the Negative(black) goes to the parts being cleaned.
Now just fill up the container with clean water to what ever level you need depending on the length of part(s) being cleaned. I use the bucket with the gallons marked out so I know how much water I'm putting in. As far as Baking Soda, I followed the rule in the above links, one tablespoon Baking Soda per one gallon of water. This formula has worked fine for me so far. Some guys just pour the baking soda in with no set measurements.
You can use old copper bare wire or steel wire to hang the parts from the center support (Negative lead). I use copper since I have plenty of scraps around and just double or triple the wire for heavier parts.
As stated earlier, my method here is more for convenience than anything else. By hanging the anodes, instead of clamping or bolting, it makes it easier to remove the anodes for cleanup or storage. This setup took me about 2-3 hours to fabricate.
Read the two links mentioned at the beginning. They will give you more details as to what and how for an electrolysis tank. It will give you a better understanding as you build yours. By no means am I an expert on this subject. Within the last month I found out what an electrolysis set up is and how it works. I just devised a way to better suite my needs as far as the construction and use of the tank itself.
Hope this helps any one who is new to this, referencing or just wants to change or improve their setup. Any suggestions, ideas or comments, please post.
By all means, please post your own electrolysis setup.
UPDATE: Per suggestions of others with the cross member possibly coming in contact with the anodes, I installed heat shrink tube at each end. Roughly 6" of heat shrink tube and left a 1" area uninsulated on one end to attach the Negative feed clamp. I also wire wheeled the piece on the bench grinder and applied PB Blaster Penetrating Oil to keep it free from corrosion. This should help with the electrical conductivity.
Last edited by Pupuhd; 10-13-2011 at 02:23 PM.
Very class act.
Nicely executed, and the discussion with photos, equally splendid.
I think most instructions recommend Washing Soda, but baking soda works in a pinch.
The amount is really not that critical. When the bubbles slow down, some people think they need to add more soda, which is not the case. The anodes have to be cleaned to reveal clean steel again, like the last photo showing the wire brush.
Heat baking soda above 140 F and it will gradually decompose into washing soda. Put a bit in a toaster oven at 350 F for a few minutes.
What a great description! An economical construction, too.
Only improvement I can think of would be to make the electrical connections to the anode rods as quick-disconnects to facilitate removal of the anodes for cleaning.
Maybe secure the rod from which the workpiece (cathode) is hung to prevent short-circuits? Might be safer for unattended operation.
Still, a great description of a simple, inexpensive, but effective electrolysis tank.
If you're really working the tank hard those rebar anodes will decompose into sludge, so its maybe worth considering some kind of joint so the anodes can be replaced. Consider avoiding use of stainless for the anodes, they lasts way longer than rebar release chromium into the bath- undesirable.
Yes true. In my case this design is for the casual to moderate use. If at any point the anodes have to be replaced, then I'll just cut off the L shape hooks and re-weld them to new rebars. Thanks-David
Originally Posted by Greg Menke
I saw one setup that eyelet insulated connectors were used at each end of the Positive lead wire between each anode, total of ten eyelets for five anodes. One suggestion I received, which I will do, is use wing nuts instead of the outside nut at the anode. This way no tools required and very simple to build.
Originally Posted by SouthBendModel34
See UPDATES at the bottom of the original post for your second comment.Thanks-David
Very nice rig, but I had the same thought... Steel doesn't last very long.
Originally Posted by Greg Menke
Stainless is a VERY VERY VERY BAD idea. Google hexavalent chromium... it's EXTREMELY toxic.
The best electrodes I've found are carbon graphite rods. I found some at auction but have read that they're available at welding supply places.... also (of course) eBay. I've been using the same ones for at least 200 hours and they're still mostly intact. They also leave the solution much cleaner.
Here is a cinncy #1 coming out of the tank base and all. Hit it with a high pressure washer and it's ready for primer.
You are making a simple job difficult. Put it in the steel tank, don't let it touch the sides or bottom. Dump in some soda ash add water. Hook positive from charger to tank and negative to object.
I retired this 500 gal fuel tank because it was getting thin and have used it many times for derusting and it has not sprung a leak yet.
My little one is a 55 gal plastic tank with a 55 gal steel drum split long ways and inserted in the plastic drum. Every part of an object is in line of sight and no piddiling with a bunch of rods. Kenny
Let me run this by you guys. I have a rusted up motorcycle fuel tank. Can I fill it with water and soda, drop a carbon or steel rod in the filler neck (avoiding contact with the tank), hook the battery charger up "backwards" and blow the rust out of the tank?
I am thinking it might work to hook the positive to the anode hanging in the tank.
Make sure the positive don't touch the metal.
If you go the other way, it will get worse I would think.
Someone will know for sure. Kenny
As Mike stated, the Positive has to go to the anode going in the tank, the Negative attached to the tank. You will futher rust the inside of the tank if you reverse it.
Originally Posted by Mike C.
I was thinking of doing the same to my 80 gallon compressor tank. Plugging all the ports except for the top one, then inserting a 1/2" rebar. The point around at which the rebar may come in contact with the tank can be insulated with several layers of heat shrink tubing.
Blasting it with air will not remove the black ionized oxidation residue left by the electrolysis. It has to be scrubbed off with a 3M finishing pad or stainless steel brush. However I was thinking of using some Rock Polishing Abrasive(stuff they use in a rotatry rock tumbler) that can be turned inside the tank to remove most of the stuff then rinsing it with water. Let in dry then spraying some penetrating oil inside. My understanding is that a 2 stage compressor will blow oil into the tank anyhow.
In your case, you can use the Rock Polishing Abrasive inside your tank and just shate it around by hand, then rinse, repeat, rinse, repeat, rinse, you get the picture, until your happy with the results. You can use a flashlight and small inspection mirror to look around the inside of the tank......good luck-David
The rock polishing stuff is sand I think. That might be worse than rust unless the tank is made with no place for any of it to hide. Kenny
Motorbike gas tanks can be done with a handfull of old nuts and bolts inside.
Wrap the tank in pillows and place in a clothes dryer. "Air Fluff."
Do not tell the owner of the dryer!
Or so I have been told.
These photos are the best explanation I seen or how to setup. You can say the work is negative, etc, but a picture is worth 100 words.
I never tried this method, but heard and read how well it works.
((Did anyone have a source for those heavy industrial buckets? )) Never mind--- I re-read it. I'll try home depot. Words vs. pics.
Thanks, guys. I have used the nut, bolts, and chains sloshing around inside, but it only removes the crusty rust. That's why I want to try the elctrolysis method. I am thinking maybe tumbling media and rig up a vibratory set to scour after electrolysis. As usual , lots of great info here. Maybe I can get the old rotary back on the road.
You can definitely use electrolysis to clean the inside of your tank.
Wrap the electrode in some nylon window screen and secure with a couple of tie wraps. That'll keep it from shorting but still provide a path to the electrolyte.
I'd definitely use carbon electrodes if you can lay your hands on some. I'd also set it up so you can hang the tank in a plastic tub with the filler facing down. This will help the accumulated crud flow down and out rather than pooling on the bottom and clogging up the fuel passages.
I did the "wrap in lots of blankets and put it in the dryer" method. Despite using 3 large padded moving blankets, I ended up with a nice dent on the side of my tank.
cement mixer,large foam blocks and a handful of stones,nuts or something with corners on it.
Originally Posted by Mike C.
run it for a while,flip it and run it some more.
i have heard of people strapping car gas tanks to a jacked up tractor wheel and idling tractor to tumble tank.