I know many of us have started marking our ingots. I've been using steel stamps for a good while but have not found a really good way to fasten 2 together to form initials like WW, PB, ect. I've used "C" clamps, turn-buckels, ground rod clamps, ect but nothing really worked great. I mean, they would be ok for 15 or 20 ingots but would eventually get loose. Well, I bought a cheap set from Harbor Freight and tack welded a few together. I started with the basics, PB and WW. I used an upside down "M" for the 2nd "W".
A few weeks ago me and Biggin had our annual smelting day and stamped 616 ingots at the end of the day. They worked great, wish I had done this sooner! Oh yeah, I bought the 3/8ths size.
If you guys are not marking your ingots I encourage you to start. Sooner or later they will find a way to get mixed up.