I broke down and picked up more than just beans on my last trip to Sweet Maria's. OK, it wasn't like the Quest jumped off the shelf into my arms, but at least it makes a better story.

Unpacking it was a lot of fun, and it is a lot smaller than I had imagined. I noticed that it seemed as though the door end of the roaster sat higher than the fan/control end, but didn't think much of it until today.

My first two roasts, with EricS' probes installed, had my senses puzzled. Things were somehow ahead of the temperatures that I had seen in quest-m3-roasting-instructions-t15989.html, the drying phase sure smelled like it was over long before the 150-165 C suggested there. The beans looked like they were darkening quite a bit before getting anywhere close to the 190 C suggested as a pre-1C switch-over point, but maybe that was that I had let the MET get too high. Sure enough, the first pops of 1C were at 167 C (indicated). Second crack hit around 188 C, and I dumped at that point.

A second run with the same Panama bean let me better control MET, but sure enough, 1C first pops were around 170 C again, with the roast stopped around 178 C. By inspection and smell, it is somewhere around FC, with the beans starting to round and smile a bit more.

So, I'm puzzled. I checked the positioning of the BT thermocouple and it wasn't bent and was within a couple mm of the drum's internal struts, but not striking them. I checked that my meter was set for type K to match the thermocouple, and that I was in Celsius mode both on the meter and in Artisan. I checked the BT thermocouple against a type T that I have in boiling water, as well as a Thermopen, and all were within about a half a degree C from 100, which makes reasonable sense.

Could it be that the roaster's angle (~6" from the front screw that mounts the legs to the drum to the counter, but ~ 5 5/8" at the back screw) is keeping the 150 g charge of beans further back in the drum and not covering the thermocouple? I do get beans in the trier and see them against the window, so it isn't that they don't move up to the front at all, but...

Any suggestions would be greatly appreciated. I don't expect to replicate anyone else's temperatures, but I wasn't expecting to be something like 30 C off.

Maybe try the actual stock roaster with the stock dial thermometers, and eliminate all the added sources of error you've saddled yourself with.

It certainly looks like the angle of the drum makes a very significant difference in the BT measurement. After tilting the half-sheet that the roaster is sitting on to make the drum level (as measured by the leg-mounting screws), about 3/4" over 15" of the length of the sheet, 1C with the same beans was in the 195-204 C range (as measured), about a 25 C higher measurement.

I would be curious to know how level (or not) other M3s are.

My M3 is not level, the side with the power socket is a bit lower than the side with the control pane.

My roasting table isn't all that level!

Edit: Actually I just checked with a 5 ft level, and it is actually pretty good. Amazing.
I think you might have the BT thermocouple in a little too deep.

There are also now multiple easy spots for the ET thermocouple, the chute upper right screw hole was the normal spot when the thread was written.

Thanks for this thread. I just picked up my M3 last week and mine wasn't level by a long shot! I had to push down on the front part of the roaster (where the trier is) until the bottom of the drum touched the ground. After doing this a few times it leveled off a bit, but still not perfect. It looks like this latest batch of stands need some adjusting. I never thought that this would make such a difference, but it seems as if we are running into the exact same issues.

There was a thread about this a while back (I think it was the large M3 thread). Some models are tilted backwards, some forward. Mine is an earlier model and it was tilted quite a bit backwards as well.

My M3 is level. The BT probe measure the bean temperature by physical contact with the beans falling off from the rotating blade inside the drum. If the vertical angle is leaning towards the motor side instead of the door side, beans could not touch the probe so your probe was only measuring ET (environmental air temperature) but not bean temperature. If it happens that you've set low fan speed and high heater power, the internal ET could be lower than the actual bean temperature. So, I suggest you bending the leg a bit to make the whole thing horizontal.

I have mine set on top of a large square bamboo cutting board that is nice and flat ( it wont warp) right underneath my range hood. I've found that I have to fold up a handtowel or two to raise the back end about 1/2 inch, to bring the unit ever so slightly tilted so that it doesn't retain beans when I lift the dump chute. My first couple of roasts, I would have 8 or so beans that were still bouncing away at the back of the roaster and never fall out.

I had read this thread the day before my last roast, two days ago, and thought I'd double check, Even with the towels in the back, it's not horribly off level, front to back.