Yesterday I finally inserted a thermocouple from SweetMarias into my roaster. I drilled a small enlarging hole in the vent cap and another in the chaff cup and threaded it into the beans about 1/2 inch above the base plate and away from the center holes. What I measured amazed me. I never knew that the bean temperature was getting so high at my settings. i tried to measure the roaster gage temp and the t cpl at the same time to get an idea of what is going on. I was roasting the Rwanda beans that have received such rave reviews here. Here are the settings and results:
Stage 1: 350 degrees for 4 minutes
Stage 2: 390 degrees for 3 minutes and 30 seconds
Stage 3: 460 degrees for 45 seconds
Stage 4: 390 degrees for 1 minute
Time of reading Roaster temp Thermocoouple Temp
30 seconds 288 234
1 minute 311 304
1minute 30 seconds 318 324
2 minutes 324 347
2 minutes 30 seconds 330 360
3 minutes 331 368
3 minutes 30 seconds 345 373
4 minutes 345 388
4minutes 40 seconds 376 415
5 minutes 383 421
5 minutes 30 seconds Lost Lost
6 minutes 392 435
6 minutes 30 seconds 395 438
7 minutes 400 452
7 minutes 30 seconds 405 454
8 minutes 409 488
8 minutes 15 seconds 442 500
8 minutes 45 seconds 408 468
9 minutes 15 seconds ? 459
I hope this chart will be useful to other IRoast users. By the way, the beans turned very dark brown and oily. Next day (today) i tried some and it was drinkable and enjoyable, but I live in the Pacific Northwest where we are used to such coffee. I worry about the thermcouple because the plastic insulator on the end fried and got black. Probably no more carcinogenic than that batch of coffee though.