I just use my old rock tumbler from my gold business. I think I got it for 20.00 20+ years ago and still working fine. Basically a heavy duty round rubber cylinder that has a liquid sealed top that you put on a rotating roller. I put kerosene in and put the chain in, close the top and let it run for however long I want. Uses very little electricity so I usually just let it run non stop. Put in dirty chain clean one comes out.