I'm new to this but have read the thread through more than once. Just made my first batch of screened powder and it's drying on my truck dash now. I'm making charcoal in a dollar store candy tin in a small kiln which I now control with a home made PID controller that I set at 550 (second batch). When I checked it wasn't done so put it back in at 625. It started to smoke then I got tied up cooking supper and didn't watch it for about 30 min. When I checked it it had stopped smoking. Well I figured I blew by the sweet spot but did an ash test and it came out about 2.1%. The coal was black - I was hoping for Brown. Now my question is how to judge doneness when you can't see the smoke except around the cracks of the kiln
door? Also, I noticed when doing the ash test that some of the combustables seemed a bit harder to burn. Just an observation - probably not worth much as the n=1. Thanks for the thread that you've all added in to for the past 10+ years! Good stuff from lot of folks that think about what they're doing.
Rick