I’ve owned this bench power supply forever so it was only procrastination that kept me from trying this out. The process is pretty easy once you get good contacts and enough steel. If you try this don’t use stainless steel, I have read that chrome will leech out into the solution and then you’re dealing with nastier stuff than just rusty water. Use something that you know is only mild steel.

Once the rust is gone I will try soaking it in kroil, hopefully the rusty spindle will come out of the knob then.