Electrolysis. It is a a great process and will get rid of the rust, or at least make it easy to brush off. I have used it and I will continue to use it at times.
The draw backs are this.
- It takes a little time to get set up.
- You need to get it set up and it typically takes over night for most planes.
- You need a plastic container big enough for the piece you’re de-rusting and you need a battery charger.
I will guarantee once you’ve used it you will continue if you plan to do this often.
The advantages.
- It’s cheap
- Once setup it is easy
- Its one of the safest ways to derust
- If you leave a piece in to long, nothing will be harmed
- No harmful chemicals
Is it safe? The solutions used are not hazardous; the voltages and currents are low, so there is no electrical hazard. No noxious fumes are produced. The method is self limiting: it is impossible to over clean an object.
Small amounts of hydrogen are emitted in the electrolysis process. Good ventilation or an outdoor work site is all that is needed.
Why electrolysis may be the best option: Electrolytic derusting By Ted Kinsey on Stovebolt.com
Go get a rubber or plastic tote or container large enough to hold what you want to derust, (although you can do half at a time by cleaning one end and then the other. Lap marks should be minimal if the cleaning was thorough) a battery charger, some Arm and Hammer Washing Soda and a long piece of metal (like a length of rebar, or steel rod or bar). You can also use Stainless steel, but it is said to be a health hazard, so I recommend sticking with metal.
About a tablespoon of soda to a gallon of water is good. Also according to Ted Kinsey’s article, household lye will work just fine as well. It’s a tad more nasty — always wear eye protection and be sure to add the lye to the water (NOT water to lye!!!) The solution is weak, and is not harmful, though you might want to wear gloves. NOTE: It is the current that cleans, not the solution; nothing is gained by making a more concentrated solution — DON’T!
Add water and about a table spoon of Washing soda (I’ve found baking soda doesn’t work nearly as well) to each gallon of water. I like to error on the “more”side, this stuff is cheap. Cost doesn’t seem to be much of an issue.
Stick the rod in the water so it doesn’t touch the metal you’re derusting. Connect your positive side of the battery charger to this rod, bar, or whatever you chose. Try to make the rod (or other piece of metal) as big as practical.
So again, POSITIVE SIDE TO THE BAR OR ROD, NEGATIVE SIDE TO THE RUSTED PIECE.
Clamp the negative side to the metal piece. You may need to clean a spot up enough to get contact. Let it “cook”for a few hours. Over night if its really bad. Cooking to long doesn’t hurt. If there is no rust to act on, its just idling.
I struggled with electrolysis a little in the beginning. It always took to long. At lot longer than it should have. Somewhere through another conversation I mentioned I had a new battery charger and it didn’t seem to work right for electrolysis. I discovered putting a battery (old dead battery) inline between the charger and the vat. What a difference. I had a dead garden tractor battery so I stuck it inline.
The battery is hooked up just like you were to charge it. Then I run a line from the positive post to the rod in the tank, and a line from the negative post to the rusty old tool. You can run multiple lines to multiple tools from the negative side. I just used regular #12 copper wire. I just split a section of plain old house wiring.
In just seconds and an old rusty block plane created this reaction.
Those are Bubbles you see!
Here’s what went in in the morning.
This came out early evening:
A couple of squirts of WD40, polish the brass and wire brush the outside for this:
In the morning the solution looked like this. It removed some gunk for sure.
It can’t get any simpler. If it sounds at all complicated, re-read. If you think its complicated stop thinking. It so easy its scary.
So How long does the solution last? Forever, though the loosened rust will make it pretty disgusting after a while. Evaporation and electrolysis will deplete the water from the solution. Add water ONLY to bring the level back.
What about screws, pivots, etc that are “rusted tight”? The method will frequently solve these problems, without the need for force.