I'm 2 steps below a novice machinist so I can't contribute much toward that end, but I've been operating and maintaining rusty old junk machinery as a logger, farmer, railroader most of my life.
The last 35 years I've lived here in Southeast Alaska and maintained equipment operated in salt water and high humidity (at least it's cool unlike coastal Texas or Florida ). Commercial fishing boats, sport boats, airplanes and vehicles are all subject to some pretty severe corrosion, everything is in a hurry to return to it's natural state. I've used just about every method available to clean-up rust; hand tools, power tools, wire brushes, grinders, needle scalers, elbow grease and chemicals. I like sand blasting, I just bought a new sand blast cabinet and I have a pressure pot for big stuff, for heavy rust on heavy iron it's fun to watch new shinny metal appear.
Several years ago I was restoring a old Dodge Power Wagon. Sand blasting tended to destroy sheet metal parts, it erodes away the thin metal but also causes it to stretch and distort. I learned about electrolysis. What a wonderful way to clean up rusty parts. I cleaned up some sheet metal parts that I thought were beyond salvage, sandblasting, wire brushing or chemicals would have destroyed them. After a dip in the electrolysis tank they looked almost new, you could even see the stamped part numbers.
I expanded to a 30 gallon plastic garbage can and a larger battery charger and started doing all the steel parts that way. I tried different electrolyte mixes ( plain water is an electrolyte, additives just make it more efficient) and discovered salt water worked best, I just go down to a dock and fill up buckets with salt water( I wash after in muratic acid then water and paint immediately). Any dc voltage will work, but the more current the faster the results. My 24 volt battery charger worked great until the smoke leaked out of it. The sludge that comes of the part and the anode build up in the bottom of the tank and when it reaches the part it creates a short circuit and out goes the smoke.
I had a batch going one time and was doing some oxy/ac cutting. I kept hearing loud pops, almost like a firecracker. I realized the sparks from the cutting were igniting the hydrogen gas bubbles escaping from the electrolysis tank. I was outdoors so there was no danger of hydrogen accumulating and causing a fire or explosion, but it's something to be aware of.
I got a 20amp 12volt power supply and a large fish tote from a local fish cannery to clean the larger parts from these old trucks, but life has put that project on hold for a while and I've only done a few small parts lately. Most of the work I've been doing lately is on small airplanes and electrolysis doesn't work on aluminum.