So, I started with a dog bowl and a Wagner paint strip heat gun. But within a few roasts found lost without any idea of the heat I was applying. So, I added a Amprobe TMD-56 thermo logger. I found the bottom of the bowl, if insulated, followed bean temps reasonably well. And a probe above the beans acted like a ET or MET probe. But, my roasts still had issues with ashiness. SO, I upgraded the heat gun to a Master vari-temp, but had trouble holding. At the same time, I was feeling I wasn't good at agitation. And so the contraption was created. . . http://www.home-b...82-40.html
Today I roasted batch #16 (all about 140gms of greens). Which was #6 with the contraption. This time I hooked up the Amprobe to my laptop running Artisan. I had troubles, but nothing I cannot fix with next roast. Overall the my roasted coffee is improving. Still struggling getting the roast times down under 14 minutes. I've been creeping the heat gun hotter and hotter. Today I found my extension cord was limiting my gun heat output. I put a KilloWatt on the heat gun, which showed a rather significant drop in power. Another lesson . . . Easy to fix.
So, further upgrade to this roaster is more insulation around the bowl. Holding more heat in means lower heat gun temps required. I would also like to craft some sort of chaff collection. It would be great to have control and more airflow. No rush on these. But I am thinking of options. . .
Overall, I am pleased I went this more difficult route to home roasting as opposed to buying a inexpensive roaster. It likely will not produce better coffee, but it has been a great learning tool.