Gray, just wanted to say thanks! This thread has motivated me to make char. I used the same method you explain - a 50gal metal halved long-ways. Worked great! Bought a few inexpensive grinding wheels from Harbor Freight to cut and it worked great for me. I had a stack of split and dried water oak that seasoned for a year or so. The pieces were fairly large. To finish a burn took about 2.5 hours. The longest part of the process was building up a good, hot coal bed with smaller twigs and branches. After that, the bigger material and split wood charred quickly. The flexibility of the metal drum proved useful too. I walked around the drum and kicked the corners to make the logs settle better, which seemed to help choke and starve the underlying coals of oxygen. I’ve made ~70 gallons in total. Don’t have any immediate plans for it but I’ll likely charged it with comfrey, various weeds, and chicken litter.
Anyway, just wanted to say thank you! This has been a very encouraging and motivating thread. Not to mention making this stuff is rewarding!
Andrew