So, I'm no expert on this, and I'm just learning to love cast iron, but I thought this was the place to put this. Merovech, if you want this post moved elsewhere just let me know...
Cleaning Really Cruddy and Rusty Cast Iron with Electrolysis
I picked up a couple of very cheap small skillets (#5 size) for a total of $8. They weren't in good shape, but when I got home I realized the crud and rust went deeper than I thought. There are other methods of cleaning, but I decided to try electrolysis. There are better writeups of the how and why of electrolysis out there – I decided to post to show that this is easy-peasy to set up, even for somebody who hasn't had more to do with electricity than flipping switches in decades.
I got my directions from http://www.wag-society.org/Electrolysis/electros.php
. Looking over the 3rd option (A Simple Setup) I realized I already had almost everything I needed:
6 gallon bucket
2 pieces of heavy gauge solid copper wire
Empty Coffee Can (and tools to open it up as pictured: Can opener, Tinsnips, Hammer, Punch, Screwdriver (aka another punch))
2 decorative bamboo trivets
Pliers (to bend wire)
Car Battery Recharger
1) Open bottom of coffee can 85% of the way around, leaving bottom still partly attatched. Cut side with tinsips, so it unfolds.
2) Strip several inches off one end of both wires
3) Punch 2 holes in coffee can – thread 1 wire thru and crimp/bend wires&can edge so that it stays attatched.
4) Wind other wire thru and around hole in skillet handle.
5) Place coffee can side down in bottom of bucket
6) Place Bamboo racks in a v-shape inside sides of coffee can.
7) Place skillet in the V of the bamboo racks. Look and feel around to make sure there is NO CONTACT AT ALL between the coffee can and the skillet, and that the skillet is held securely so it won't move and come into contact with the coffee can if the bucket is bumped.
8) Fill bucket with water so skillet is entirely under water
9) Add generous ½ cup of washing soda, stir with hand to dissolve well. (1 Tbsp per gallon is needed, but measurement does not need to be precise.)
10) Plug in battery charger to AC current.
11) Attatch wire to the skillet to the BLACK clamp of the battery charger.
12) Attatch the wire to the coffee can to the RED clamp of the battery charger
13) You've done it! Little bubbles of gas should be almost immediately visible on the skillet.
(Yes, I am a doofus - I accidentally put the black wire on the anode and the red wire on the cathode, which is backwards. The charger clamps are hooked up correctly outside the pic.
I made sure it's in a place that it's not going to be disturbed – and that is well ventilated! That's hydrogen gas bubbling up and if it got a chance to collect it would be flammable.
Note – the piece of metal used for the anode (the coffee can) is going to get really crudded up, use a piece of (ferrous) metal that you're willing to ruin. (It is called the sacrifical anode for a reason!) Other pics show using metal clamps to hold the skillet and anode – but I'm pretty sure my husband would have words for me if I used his good clamps for this!
This took me 1 trip to the store to get wire and something to hold/insulate the pieces. A plastic dish drainer in a square sterilite or rubber maid container would be even easier and more secure, I'm planning to get those. This is just the set up I cobbled together with as little new as I could. It took me about an hour, total, of messing around and running up and downstairs to find things, to get this up and running. It would likely take even less time for an organized person!
Within an hour the water was looking grey/orange, and was cloudy with foam and crud 7 hours later. At 7 hours, there were loose pieces of crud that could be easily removed from the skillet with my fingers but still more to come off. (TURN THE CHARGER OFF AND UNHOOK IT BEFORE YOU CHECK THAT!) My first skillet is still in there. I will post before and after pics once it's done…
"When someone shows you who they are believe them" M. Angelou