Almico wrote:Everything is reading F, but the shutoff circuit might not make the switch when I changed from C to F, although that makes NO sense whatsoever.

Nothing else makes any sense, either, so at least things are consistent.

Given that the roast was undercooked, I'm going to assume the roaster is correct and Artisan is wrong.



I put the ET probe where the BT was and the temp jumped to 400*. So it's not the probe.



Still warming up. How late ng should a 5kg roaster take to get the 400*? At this rate, it will be over 1/2 an hour.

Found one issue. The probe I have is a J-type, not K. But I switched the driver setting and thenPhidget config in Artisan and it's still reading hot.

Getting there...

I did a Brazil roast well into 2nd. 39/41 Agtron.
Also a Costa Rica which went long, but it looked lightish and measured 60/75. Good news, it yellowed at 300* and 1C was 386. We're getting somewhere.



Not sure why this roast ran out of steam. I charged hotter and only 6#. I turned the heat down to 25% till turning point, then 80% all the way through Maillard. It just kind of died. It's going to be quite the adventure learning this roaster. But I have two coffees to cup for tomorrow.

Almico wrote:Not sure why this roast ran out of steam. I charged hotter and only 6#. I turned the heat down to 25% till turning point, then 80% all the way through Maillard. It just kind of died. It's going to be quite the adventure learning this roaster

There are two heat adjustments with this roaster. One is the gas and the other is air flow. Too much air flow will rob the 80% gas heat. So if you didn't want to add more gas, then try slowing the air a bit.

Almico wrote:But I have two coffees to cup for tomorrow.

And the verdict is...?

Just curious, but how does one test the heat and speed of a gas roaster? How do you know how responsive? Are there tests that gas roasters do when they get a new machine?

Are you able to hit your targets with small and large batch sizes?

crunchybean wrote:Just curious, but how does one test the heat and speed of a gas roaster? How do you know how responsive? Are there tests that gas roasters do when they get a new machine?

CarefreeBuzzBuzz (our resident Artisan Guru) shared his personal technique to explore this. It was my impression that he used a static gas setting that would yield first crack in less than 10 minutes in concert with a similar, native charge temp. Using this baseline you conduct several test roasts with static fan settings & incrementally adjust from low to high in order to discover what is the optimal convection parameters for your system.
Alimico mentioned procuring floor sweeps from a local roaster, MillCity Roasters sells "seasoning greens" and C grade coffee can surely be found at your favorite supplier. Repetition & the freedom to experiment is an often under looked tool for discovering best roasting practices. A big sack of disposable coffee is the best investment you can make.

So...we're making some progress. Coffee is going yellow around 300*F and I'm getting 1C around 380. So far, so good. Although it is almost impossible to hear 1C. I have to put my ear to the trier hole in order to hear anything. The ∆ET dip helps.

First the coffees from the other night. The dark roasted Brazil was very nice. It was a long, winding roast, but to no real ill effects. It was very sweet. I can't wait to tame this beast to real dial it in.

Although the Costa Rica went longer than I usually roast it, it was lighter than I'm used to with no underdeveloped or baked flavors. Being on the light side, I'm going to give it a second day of rest.

I did a few more roasts tonight. Something else seems amiss. Supposedly this is a 5kg roaster, I tried a 9# roast and it took 18 minutes to finish. I next tried 6# and it still ran long. Then I tried 5# and this is the profile:



Don't mind all the ET noise. I moved the ET probe to a chimney bolt hole right over the trier and every time I pulled it, the temp jumped.

The big issue is I charged pretty hot, kept the gas at 100% from charge through Maillard and yet the RoR sags badly from dry through 1C.

I had the exhaust fan on and damper at 20% open throughout. Closing the damper did not affect the RoR.

I think I screwed up on the gas nozzles. I drilled #55 holes and according to this chart http://web.go-spi.com/sinclairdev-new/w ... -Chart.pdf my BTU capacity is only 18,888. It should be 55,000 or even 75,000, like the Mill City 6kg roaster. I need to drill bigger holes, like #39.