Electrolysis: My setup

kendallkirk

Forum Supporter
Joined
Dec 29, 2008
Messages
42
Location
Pendleton, SC
I have been using electrolysis to clean old iron tools since long before I began swinging a detector and digging in the dirt. Just thought I would share my setup because it's not influenced by some of the ones here and may offer some new ideas to everyone.

Disclaimer: I am not suggesting that you do this, just telling you how I do it. Research all safety aspects in everything you do. For more research on safety issues, etc., please search internet for "electrolytic rust removal" or "electrolysis + rust removal" and you will find a number of sources.

Sounds complicated, but it's not...I'm just detailed. Bear with me here and I know you will find this worthwhile. If you're going to want to clean ferrous parts that you dig up, this is the only effective way in my opinion.

There many other threads in this "Make it or fix it yourself" section that have other methods detailed. This is my method. I do not use stainless steel for my sacrificial anodes because chromium is then dissolved into the electrolyte solution. Dissolved chromium can be toxic even on skin contact.

What you'll need: 5 gal plastic bucket, 1 AC/DC cell phone charger (wires clipped and stripped near plug that goes into phone...any AC/DC transformer will do...AC/AC will not do), 2 empty large baked bean cans (or other...coffee cans also work), water, baking soda, light gauge wire, alligator clips, and a volt meter. For larger parts to be cleaned, rubbermaid containers or plastic drume work well and use more cans (to surround object). For longer skinny parts, a section of capped plastic gutter works great. Any plastic container will do.

Cut top and bottom out of cans with can opener, then cut along height of cans with tin snips and gloves and straighten out. Cup it a little so it will free-stand in bucket. Strip wire on AC/DC transformer (make sure bare ends aren't touching), plug in to wall, and check polarity with volt-meter. Important: Positive lead goes to sacrificial anode (cans), negative lead goes to part (chain in your case). Mark them now with tags of masking tape and a Sharpie.

Add water and maybe 1/2 cup (can't remember correct proportion here, but I can tell you how to adjust to get it right...it will actually depend on the voltage of your transformer anyway). Mix until dissolved. With transformer unplugged and the two bean (coffee, whatever) cans standing upright in bucket (one on each side), hook aligator clip from positive lead on transformer to one of the cans (impt: above water line or alligator clip will oxidize away with time). Take another short piece of wire with two alligator clips on either end and hook one to each can above water line (so that both cans are hooked to the positive lead in series. The idea here is to sort of surround the part to be cleaned with the cans (sacrificial anodes).

Hang your part to be cleaned from a piece of baling wire or something (I use aluminum electric fence wire), suspended from a board (pipe, dowel, anything strong enough) that spans the top of the bucket between the cans sticking out. Part to be cleaned should be completely submerged, as close to the center of the bucket as possible, and not definitely touching either of the cans.

Hook an alligator clip to the negative lead from the transformer and clip it to the part to be cleaned. Several clips can be daisy chained together to do multiple parts at once or to clean a part that is segmented, where electricity will not conduct well from one segment to another. This will be the most troublesome thing if you're cleaning something like a chain because the individual links will not conduct well from one to another...an alternative is to put the chain in a steel or aluminum mesh bag of sorts, bind tightly and just hook one clip to the bag (this is how I clean many rusted nuts and bolts or other small parts at one time).

Almost done...I plug the transformer into a gfci outlet for safety. Before you plug in, make sure that there are no places where the part is touching the can or you will have a short. Plug it in and closely monitor the temperature of the transformer box for at least the first 20 minutes or so.

If it is getting hot to the touch then you need to dilute your electrolyte solution (there is too much conductivity in it). Just pour out some of the solution (10-20% of it) and replace with tap water. THIS IS IMPORTANT: Fix the problem if transformer is getting hot...otherwise it may explode, releasing potentially harmful compounds into the air.

If it is warm to the touch and seems to stabilize without continuing to increase in temperature, then your solution is good.

If it is cool to the touch, then consider adding some baking soda to the solution.

There is a way to get this exactly right by measuring the resistance and comparing it to calculations from specifications on the transformer, which I can explain if you're interested, but this "hot, warm, cool" test works fine for me. Different voltages will require different electrolyte strengths (or different concentrations of baking soda).

In time, the water level will drop and it will get murky. There is never any reason to change the electrolyte solution nor to add baking soda once you have it right. Just keep adding water weekly or monthly to make up for evaporation as needed. It is environmentally sound also to never dump the solution due to heavy metals that may be dissolved in it. If you're never going to use it again, allow all of the water to evaporate and then dispose of the bucket/dry contents properly. I keep two electrolysis setups continually running and just keep adding water every once in a while.

What you should see immediately in the bucket is small bubbles forming from your part to be cleaned (if not, then you are not alligator-clipped well enough to the part). These bubbles are hydrogen and oxygen from the splitting of water. The action taking place is an electrolytic reduction that is actually converting some of the iron oxide back into iron.

Since the hydrogen and oxygen can be flammable or even explosive if allowed to accumulate, make sure to set this up somewhere outside (I do mine on a screened porch with no problems). The small amount of hydrogen and oxygen is not a big deal unless it can accumulate.

Depending on the size of the part and the current of the transformer, you can periodically (maybe every 6hrs, maybe 12 hrs, maybe 2 days, you'll have to experiment with time period) pull out the part occasionally, brush it under cold water with a brass wire brush. The scale will get easier and easier to brush off each time. For lightly rusted parts, I only have to brush once (i.e. only one cycle of electrolysis) and then I'm ready to preserve (no more trips back into the bucket). Make sure to unplug transformer any time you reach into the bucket. And have dry hands when plugging/unplugging. If you use a power strip, then you can just flip the switch.

Once you're happy with the amount of cleanliness (there's no reason why all rust won't all go away with enough time in the bucket), do a final rinse/wire brushing, immediately dry part with towel or paper towels and then preserve shortly thereafter or it will start to rust again. Preservation can be a coating of machine oil or better yet, some clear floor wax (I heat mine in a $2 crock pot from the thrift store and brush it on with a paint brush...wax is easily removed with a hair dryer if you ever wanted to).

I know that you will find this to be superior to any other method that you try. Museums often use it to clean parts from shipwrecks, archaeology digs, etc. For steel and iron, you can leave the part in there indefinitely without any harm...if it's ferrous, the part will not degrade whatsoever with time. In cleaning other metals though (aluminum, silver, copper, etc. such as you may have with coins) you must only leave part in solution hooked up for very brief periods (15 minutes or so) and check because it will degrade these parts to literally nothing with enough time.

electrolysis1.jpg

electrolysis2.jpg

electrolysis3.jpg

electrolysis4.jpg

electrolysis5.jpg
 
I'm thinking of building one and i did not know that Dissolved chromium can be toxic even on skin contact. thanks
 
Excellent job!! Loved the disclaimer. You should consider a job as a technical writer. It is so nice to read something so clear and concise.:yes: Sure a better job than most manuals that come with anything you buy today. Thanks for taking the time. I am sure many will use it as their reference for building a unit.:yes:
 
I have been trying to do some electrolisis on my coins that I found on the beach. I guess you could do more that one coin at a time by using more than one clip. Could you use a wire mesh suspended in the water(without touching the anodes) and put several coins on it? Would the impurities from the mesh transfer to the coins?
I had a strong solution of soda and water(1 1/2 tablespoons of soda to 2 pints of warm water, (easier to dissolve)). Approx 1 1/2 cups to a gal of water. Next time I will try a lesser solution.
My transformer, 12 vdc, did get hot, but I used a frozen gel pack to help keep it cool, but I still checked the transformer frequently just to make sure it didn't get too hot. Just using the gel packs seem to lenghthen the time without stopping.
Thanks for your receipe, I will give it a try. Do you know a way you can clean aluminum thru electolisis?
 
Great write up! It sure helps alot. I have done a little experimenting with electrolysis but it always turned out bad. This guide will deffinetly go in my bookmarks and be a source of help for years!
 
I have been trying to do some electrolisis on my coins that I found on the beach. I guess you could do more that one coin at a time by using more than one clip. Could you use a wire mesh suspended in the water(without touching the anodes) and put several coins on it? Would the impurities from the mesh transfer to the coins?

Wire mesh bag should work well for batches of coins...be careful and take it slow though because they may etch quickly. If you think any have any value, think twice about electrolysis. The impurities cannot transfer (electroplate) to the coins unless they are first dissolved in the solution. I have not had problems with plating in any of my attempts. To my understanding, most metals are relatively insoluble except at low pH's (with the baking soda this is a high pH solution). I have mainly just done iron and steel parts in my setup, but I plan on experimenting some with other metals at some point. I'll post results when I get them.

I had a strong solution of soda and water(1 1/2 tablespoons of soda to 2 pints of warm water, (easier to dissolve)). Approx 1 1/2 cups to a gal of water. Next time I will try a lesser solution.
My transformer, 12 vdc, did get hot, but I used a frozen gel pack to help keep it cool, but I still checked the transformer frequently just to make sure it didn't get too hot. Just using the gel packs seem to lenghthen the time without stopping.
Thanks for your receipe, I will give it a try. Do you know a way you can clean aluminum thru electolisis?

Aluminum will come clean in this setup, but it will also etch it if it stays in for too long. Take it easy and only leave in for short periods. Test on some scrap. Please let us know your results if you try it on aluminum...what lengths of time seem best, etc. Good luck.
 
Thanks, I just completed your design and am trying it out now.

Great! If you have any trouble, please post here and we'll try to get you straightened out. Show us some before/after pics if you have any. I was going to post some, but couldn't find where I saved them. Good luck.

To others who have replied, thanks for your interest and please let us know your successes and failures so that we can all learn from it. I'm new to the non-ferrous world with these setups, so I'd like to hear any tips you have in that realm.
 
Formula for adjusting solution strength.

If you really want to hone in on the electrolyte solution strength, you should be able to use Ohm's Law: V = I x R (voltage = current x resistance).

I have never actually done this (I use the warm to the touch method described above), but it should work in theory. With alligator clips hooked to the part(s) and the sacrificial anode, and hanging in your electrolyte solution, but without the transformer hooked up, measure the resistance (Ohms) between the clip going to the parts and the clip going to the sacrificial anode.

The voltage (printed on the transformer) divided by the resistance measured will equal the current draw (amps). If the current draw calculated is greater than the capacity printed on the transformer, then your electrolyte solution needs to be diluted (dump some of it and make up with tap water). If the current draw calculated is less than the capacity printed on the transformer, then add more baking soda.

Example:
Transformer Output (printed on box): 9VDC, 800mA (equals 0.8 Amps)
Measured resistance: 5 Ohms
Calculated current at that resistance: 9 / 5 = 1.8 Amps
So, solution is too strong...dilute it a little more than half.
After dilution, measured resistance: 12 Ohms
Calculated current at new resistance: 9 / 12 = 0.75 Amps. This is less than the capacity of the transformer, so it should be okay.

Like I said, I have never really done this test, but it should work I think. If anybody knows otherwise, please correct me.
 
Well I did try your setup sort of, I took it one step further. Instead of a plastic pail with two anodes inside. I took a 1 gallon soup can, place it inside of a plastic container and filled the can with water. I didn't cut the can, except removing the lid, other than that, the is still one piece. So now the whole can is the anode. The rest is still the same. Soda in water dissolved, bridge across the top to suspend my items from, item sitting in middle of can covered by the water. The 1 gallon soup cans are easy to come by, so when they eventually create a hole in it, I will just replace the can. Yes you have to be careful not to touch the can with your item, but that is true with any set up. I'm not cleaning large items like you are, but mostly coins and a few small iron objects. I'm just experimenting, and seems to work ok .....so far.

My DC transformer is 12 vdc .3 a
Electrolylisis 003.jpg

Electrolylisis 002.jpg
 
Well I did try your setup sort of,

Neat idea...I would have never "thunk" it. It should work great. Maybe you can have a plastic tub like an oil change tub underneath so that you can capture your electrolyte when it does get a hole in it. I'm interested in knowing how long it takes to get a hole in it...thanks for the tip.
 
In regarding to new design, I have found that it does matter what type of gallon size can that you use. I you notice the inside of the can, shown in the pictures, the can is not bright and shiny. There is a coating on the inside to protect the food product that was on the inside. That coating is a waxy substance, which inhibited the transfer of electrical charge. I didn't think about that at first, so I added more soda to my mix. Still the reaction was subtle. After an hour of very little action, and transformer still cold, I added again more soda. My initial rate of soda was 2 spoons worth of soda. Each additional addition was at the same amount. After 6 scoops of soda and still no bubbly reaction, I dumb the contents of the can into the plastic catch basin and proceeded the usual way, using a stainless spoon. The transformer didn't take long to get hot, there was a substantial increase in the bubbling action around the coin.
My next test will be using a coffee style can that has no coating on the inside. When I preform that test, I will show the setup, formula and results to the forum.
 
Add water and maybe 1/2 cup (can't remember correct proportion here, but I can tell you how to adjust to get it right...it will actually depend on the voltage of your transformer anyway). Mix until dissolved.

Whe you're saying 1/2cup, I assume you're talking about the baking soda.?
 
Whe you're saying 1/2cup, I assume you're talking about the baking soda.?

Yes, 1/2c baking soda to 5 gallons water...but the exact amount will be dependent on the voltage of your transformer, how close the anode is to the cathode, etc. That's why I say to start there and then work up or down according to temperature of the transformer.
 
Thanks

I appreciate that. Your post inspired me to give this a try, along with some necessity;) I ended up using a 5 volt phone charger in one gallon of water, with what ended up being 1/2c baking soda. I used the heat test on the charger till I ended up with the 1/2c. It took a lot more than I thought it would. The can I used ended up really corroding and I changed it after about 10 hours. I lightly sanded the Shell with 320 to get it to shine.

Here are a few pics of the success.
I'm stoked with the results!
Thanks,
Christian
 

Attachments

  • low res Cleaned shells 1.jpg
    low res Cleaned shells 1.jpg
    95.6 KB · Views: 10,239
  • low res cover cleaning 3.jpg
    low res cover cleaning 3.jpg
    89.4 KB · Views: 10,143
  • low res meter cover back.jpg
    low res meter cover back.jpg
    29.2 KB · Views: 10,216
  • low res meter cleaned 2.jpg
    low res meter cleaned 2.jpg
    95.8 KB · Views: 10,147
  • low res meter cover front.jpg
    low res meter cover front.jpg
    29 KB · Views: 10,094
  • low res shell cleaning 2.jpg
    low res shell cleaning 2.jpg
    59.5 KB · Views: 10,083
  • low shell cleaning 3.jpg
    low shell cleaning 3.jpg
    53.1 KB · Views: 10,121
I appreciate that. Your post inspired me to give this a try, along with some necessity;) I ended up using a 5 volt phone charger in one gallon of water, with what ended up being 1/2c baking soda. I used the heat test on the charger till I ended up with the 1/2c. It took a lot more than I thought it would. The can I used ended up really corroding and I changed it after about 10 hours. I lightly sanded the Shell with 320 to get it to shine.

Here are a few pics of the success.
I'm stoked with the results!
Thanks,
Christian

That's awesome. I'm glad that you gave it a try and even more glad that it worked for you. I think many people get discouraged too soon when they're trying this. Way to go. I especially like your before and after pictures. When you get to the axe and dial thing and other really rusted iron/steel items, it helps to hit it lightly in one small inconspicuous place with the side of a file so that the electrode will conduct into the part. I'd try that if it seems to be slow at first.
 
As long as the electrolyte solution is not too strong, the phone charger should be a safe power source. I use transformers from phone chargers in my electrolysis tanks and one of them has continuously operated for almost a year with no problems. Even with a battery, if the electrolyte is too strong, the current draw can exceed the amperage rating of the wires used and therefore create a fire hazard...or sparking near the charging battery can ignite the hydrogen gas generated while charging. I opt not to use a battery because it's just one more thing to deal with. Watch the temperatures of everything in your circuit (battery or no battery) and as long as things stay at or below the "warm" range, you should be okay.

As an added safety measure, an inline fuse with a current rating equal to or less than that printed on the transformer can be placed in either the positive or negative line. If the fuse blows, the circuit is interrupted, the current draw on the transformer ceases, and there will be no additional heating of the transformer. I don't use a fuse, but it would actually probably be a good habit to get into.
 
Back
Top Bottom