I know a few local roasters that do fixed airflow and I've heard that from some more notable ones too I'm pretty sure. Some believe that too high early on drys out the surface, some think it causes the outside to get too hot without sufficiently heating the core, and of course Scott Rao writes to gradually increase thru out the roast. I usually increase my air when the beans turn yellow as they release more moisture. Airflow does seem like a very unexplored vague subject matter with more opinions and superstition than availible scientific research. It almost seems to be the pressure profiling of the roasting world

Scott's work has helped me a lot and I have been very influenced in my approach due to his books, but does anyone know his backstory/roasting credentials? As far as I know his cafe doesn't roast. Just curious

JK wrote:Dave do you have Projection checked in TOOLS>EXTRAS> Check mark in PROJECTION ???

Artisan projects a line out across the screen from you current BT at your current ROR showing you when it thinks 1C will happen..
I find time always creeps longer over roast due to gas and air adjustments.. So shoot for a shorter time early in roast..

Additionally, the third PhasesLCD (activated via menu Config >> Phases; tick PhasesLCDs), available since Artisan v0.9.0, does show the time to hit FCs, estimated based on the specified FCs phase temperature (also via the Phases Dialog) and the current RoR. After the FCs is reached the same LCD displays the minutes after, temperature above or phase ratio in % (the famous Rao percentage). Toggle between those modes via a right-click on the LCDs.

JK wrote:Dave do you have Projection checked in TOOLS>EXTRAS> Check mark in PROJECTION ???

Artisan projects a line out across the screen from you current BT at your current ROR showing you when it thinks 1C will happen..
I find time always creeps longer over roast due to gas and air adjustments.. So shoot for a shorter time early in roast..

If we are talking the same line, I found it too visually noisy and more linear than appropriate. I shut it off.

There are many more settings in Artisan than I use. For me, I believe that ambient temp, bean temp, delta bean temp, time, exhaust temp, ROR, and incoming air temp are sufficient. For this learning stage of my roasting, I work to focus more on the trier, examining the bean and taking in the information it provides.

• Left hand on data
• right hand on visuals/smells
• bridge the two

Lots to learn.

JavaBuzz wrote: Thought/"Experiment": Could using a perforated drum make airflow even more (or less) important?

I'm with what I think you are suggesting: the perforated drum is an entirely different beast when it comes to the function of air flow. Sometimes I wish there were more people with more experience with perforated drums to make the learning curve a bit less steep. More of the time it's a bit easier since there are fewer voices giving us conflicting information

You know, I think I'm about ready to go back to the perforated drum on the Huky. I did about 100 roasts on the perforated and now I have about 25 on the solid. What I like about the perforated, if I remember it correctly, is that it was like driving a car. Fan increases and gas increases took almost immediate effect. Whereas, the solid drum is more like driving a boat. I have to anticipate. And I see very little response with the air increase except at the end of the roast when the gas is down to almost nothing. Then the air increase acts to cool down the temp. sometimes more quickly than I want. All of that may or may not have something to do with taste, I don't know. But, it seems to me easier to get the profile I want with the perforated drum.
Then again, once I go back, I'll probably wish I hadn't. Too many choices.

bean2friends wrote:Too many choices.

I can relate. That's why I got rid of the solid drum/fast motor configuration altogether.

Maybe buy another roaster so you can have both?

It's an interesting question of whether you'd prefer your roaster to be more responsive or more resistant to small variations in inputs. I like my thick solid drum because it tends to smooth out stepped changes in heat input.

Bodka Coffee wrote:Maybe buy another roaster so you can have both?

I did exactly that. Then I sold the one with the solid drum. Learning to drive just one is enough.

bean2friends wrote:You know, I think I'm about ready to go back to the perforated drum on the Huky. I did about 100 roasts on the perforated and now I have about 25 on the solid. What I like about the perforated, if I remember it correctly, is that it was like driving a car. Fan increases and gas increases took almost immediate effect. Whereas, the solid drum is more like driving a boat. I have to anticipate. And I see very little response with the air increase except at the end of the roast when the gas is down to almost nothing. Then the air increase acts to cool down the temp. sometimes more quickly than I want. All of that may or may not have something to do with taste, I don't know. But, it seems to me easier to get the profile I want with the perforated drum.
Then again, once I go back, I'll probably wish I hadn't. Too many choices.

I've been enjoying the results from the Perf/Slow over the last few weeks. I logged 1000's of roasts on the Solid/fast configuration and I think I'll keep the new setup. I'm getting much better developed coffee at a given BT, and as a light roaster this helps a lot!...I'm still getting accustomed to steering it, but that's getting much better already.

Anyways, back to the topic at hand...Flick Flick