My First Roast on my New Machine - Inputs are Much Appreciated - Page 2

Discuss roast levels and profiles for espresso, equipment for roasting coffee.
Marcelnl

Postby Marcelnl » Sep 16, 2018, 4:46 am

info on Artisan settings can be found here; Are today's small batch roasters too inconsistent?

made a lot of difference for me.
LMWDP #483

User avatar
hankua

Postby hankua » Sep 16, 2018, 10:00 am

Nothing wrong with using a fixed IAT, I don't have that information but can roast on my 800n with a fixed gas setting using the air damper for control. I'd try bumping up the IAT to at least to your first crack temperature or even a little higher for an experiment.

Another thing to try out is to warm up the machine to the projected IAT temperature, and play around with the air/damper settings. At what setting does the machine idle at a fixed BT? At what air setting does the BT start declining? What's the lowest usable air setting?

EvergreenBuzzBuzz

Postby EvergreenBuzzBuzz » Sep 17, 2018, 7:30 am

As far as Artisan goes, you can find all the basics here. This was designed to cover the basics for new users.

https://artisan-scope.org/docs/quick-start-guide/

One thing that caught my eye was you said -
I let the roaster heat up to around 205, reduced the gas while keeping airflow max and waited until it dropped to around 195

.

Airflow at max could be fighting with your gas settings. Only you can come to learn this by doing test roasts. One way is to do a roast leaving all variables the same except one. So for example gas and drum speed are left the same. Then three batches are done with air at 35, 45, and 55. Which one gets to FC first? That setting maximizes convective heat for that gas setting and ambient conditions. Until you learn how the gas reacts I would leave air at one setting (selected after testing). As you come to understand how the gas reacts, then you can start to adjust air. As for drum speed, first figure out your range by counting manually and then pick one near the top. Mine will hit 70 (dial marker 100) on my 500 gram but I seem to like 52 better (dial marker 70).
_______________
Artisan Quick Start Guide
http://bit.ly/ArtisanQuickStart

ballpencil

Postby ballpencil » Sep 18, 2018, 5:13 pm

EvergreenBuzzBuzz wrote:As far as Artisan goes, you can find all the basics here. This was designed to cover the basics for new users.

https://artisan-scope.org/docs/quick-start-guide/

One thing that caught my eye was you said - .

Airflow at max could be fighting with your gas settings.


Hi BuzzBuzz, i am not sure but i think you weren't aware that i was referring to my pre-charge routine. To ensure i am charging the beans to a properly heated drum, before charging i let bean temp rise to a few degrees above my target charge temp. Then i reduce or turn off the gas and maximize airflow. This will start to decrease my bean temp probe reading (remember that the drum is still empty right now). Then a few degrees below my charge temp, i increase the gas again along with reducing the airflow which increases BT again. Once i reach charge temp, i charge the bean.

Okay time for an update. This is my second batch. I charge the beans at much lower temp this time which is 160C. Here's my log on the second batch.
Image

I learned that roasting by keeping IAT constant was difficult with my roaster so i focused on keeping delta BT declining (i reduced smoothing as suggested) except around minute 12 where i panicked as deltaBT was about to reach zero while i was still few degrees behind my target drop temp so i turned the gas up a bit again and end up with flat deltaBT up until i drop the beans (or was it the exothermic phase that caused this?).
For airflow, i was following Mill City's suggestion of low-med-high procedure and played with the gas setting while keeping an eye on deltaBT.

I replaced the ET probe (reminder: it's inside the bean chute just before beans enter the drum) with a different probe and managed to hang the probe without it touching any of the bean chute plate. Unfortunately, i still get low ET. This is very strange as only a few centimeters above my ET probe (closer to the bean hopper) is my analog temp gauge which read normally (above 200C during the whole roast).

I noticed something interesting: i was dropping the beans at around the same temp as my first batch (204C vs 205C) but my beans are slightly darker this time. Can you guess which is my second batch? It's the right one. Is this normal? So, how did i do this time? I think i did better. Any suggestions? Chewing the beans gave promising result but i need wait to until i brew it tomorrow to confirm any improvements.
Image