I have a later model M3 and Jim's instructions helped me a lot in my first couple roasts. The main problem is just realizing the differences between the earlier and later models. I understand innovation, but major changes should change a model number (M3 vs M4 or something) to avoid confusion. Before reading, I had put my BT probe in the ET location, since the drums are a mirror image essentially, only after reading many threads did I realize this, and luckily before the first roast. The other major difference as noted here is that the fan speed control doesn't seem to do a whole lot, I don't mind that the minimum fan speed is always on as much, but maximum seems only a little bit faster. I've been thinking of modding this, but ultimately I just don't worry much about the fan adjustment during roasting and worry more about the amps for now.

My main recommendation when starting to roast, is that although the temptation is there to compare graphs, try not to compare actual numbers (400F vs 400F for example) but rather when 1C happens and at what time and what overall shape is the graph (convex/concave on the way to 1C etc). The main reason is that differences of probe location and calibration will matter a lot for what temp you hit 1C at etc.

As you roast more, you'll get some great roasts. My first roasts were kind of hit and miss, but I was lucky to hit some great ones which I could use as templates later. Sometimes despite a plan, things just don't go according to it due to other factors, I've now started to roast in my kitchen so that outdoor temp doesn't play a factor in my roasts.

Awesome guys! I can't thank you enough

I'm just about to start roasting now and I remember somewhere Jim saying about reaching a certain MET with full A/full fan on an empty roaster?...I hope I read this right. I figured I would warm up with full amps/full fan just to see. I achieved an MET of 600F within about 8 mins. I dropped the amperage that this point. Is this telling me anything?

BTW I'm about to give Jims way of roasting another try just with some things modified...I'll post back on how I did

Here's what I did on Roast 1 (Ethiopia Aricha) [probably shouldn't have used a dry-processed bean at this point]
Preheat to 400 BT by 9A Fan "0" doors shut
At 400BT charge 150g and drop amps to 7.5. Door open during dry
At 300F Heat/Fan FULL (I didn't mark dry end on graph soon enough)
I then lowered heat and fan at 375. (I didn't write down what to for some reason)
These beans were pretty scorched from the high MET.



The second roast went better...
I warmed up the same, same bean, same charge temp. Only this time when my BT was reading 400, my MET was a lot lower 510 (compared to 550 on previous roast) Could this be because it was the second roast and drum was warmed up more?

I backed off heat to 6.5 amps at charge. This kept my MET a little more in line
At 300F I set heat to 9A Fan 7 (ramp seemed a little long so I may need to adjust here)
Upon 1C I cut heat to 7.5A and Fan 5

These beans looked 100% better. Only very slight tipping.



I'm really happy I gave this another go. I think I just need a little more practice.

Goldensncoffee wrote:The second roast went better...
I warmed up the same, same bean, same charge temp. Only this time when my BT was reading 400, my MET was a lot lower 510 (compared to 550 on previous roast) Could this be because it was the second roast and drum was warmed up more?

I backed off heat to 6.5 amps at charge. This kept my MET a little more in line
At 300F I set heat to 9A Fan 7 (ramp seemed a little long so I may need to adjust here)
Upon 1C I cut heat to 7.5A and Fan 5

These beans looked 100% better. Only very slight tipping.

I have a new M3 as well... had similar challenges so hang in there. My setup is a M3 w/ Eric's thermo kit adapter. For whatever reason the 'open' trap door preventing me from having reasonable drying times. My typical process is:

Drop 150g at 350 / 9A / Fan on 2 - typically results in about 3 minutes 300 degrees. I found it best if I want to stretch the dry time to drop at 325.
@ 300 degrees - bump up to about 10A /Fan a bit higher say 3.5
@ signs of 1st Crack / drop to 8A / Fan Full... I am playing with this section.. I don't get a great RoR when I drop the temp below 8A.

Hope this helps...

PS- I found using a Kill-a-Watt gives me a better understanding of actual amperage vs. the little dial on the Quest