I thought I’d share some profiles in the hope someone with the same set up might have something to share. The following charts are from my Hottop p with a probe installed in the bean mass via the top chute. The first chart is from the CS Logger, and for comparison the 2nd chart shows the Hottop readout and heat band settings.
Roast 21 Ethiopian - Yirgacheffe special prep
Did you record fan settings...if at all?
Yep, sure did.* From what Ive learnt so far I used the fan towards the end of thed drying stage and then at the end where the beans began to "take off".* *[smiley=smiley.gif].
Forgot to mention theres 250g in the barrel.
It took a bit of programming to get the shape the way it is (about 5 roasts) because of the "all or none" thermostat control.
Initially Id rather have had variable heat than fan, but in the long run I think Ive managed to get very reliable curve/program. First crack just before 200C just about every time, give or take for the size of bean.
Do you have any experience with the Hottop P/D?
The following is from a HottopB using a Template. The template logging is shown by the green plots (Except the rate of change at the bottom). In the template I use Plot 7 to track the fan changes as a stepped Graph with 100 being the equivelant of Zero then 120 being Fan speed 2 (F2) etc, and Plot 9 to track the Heat Changes Shown as 100%, 90% etc). When I need to take over control of the Heat from the HT program I use the heat slider to display the changes which shows as the Red plot. I used to just use the comments to show Fan changes as F1, F2 etc, which will show the changes along the main tracking graph. I seldom change the Fan speed manually, letting the HT program control that from the original program settup.
I use a Thermocouple into the Bean Mass.
Anyway not sure how relevant this is for the HT P.
Thanks Graham, its nice to see were in a similar ball park with time & temp. Once getting a handle on the heating characteristics, I now use the Ps thermostat segments (columns) to pull or lead the machine temp up (blue line).
My efforts have been spent on getting a bit of dry time, which I picked up somewhere as being a good thing. I notice you really manage hit the brakes to spread out the time between first and second which gets mention around the traps too.
After a couple of visits to second crack Ive tended to stray back to single roast, I love the smoke but am driven to chasing elusive choc/caramel flavours. Does second crack especially suit the Ethiopian?
Also, is that a 250g load?
Yes I always use 250g. Keep in mind the temp graphed is based on the Thermocouple & placement so comparisons between setups will depend on where yours is situated. But at least you can make good comparisons relative to your own roasts.
The drying time is also when I ramp the fan up to 2 in the beginning to try and clear moist air a bit. Not sure if it actually makes any difference, but I also read about that at some stage somewhere.
Rightly or wrongly I tend to take most beans just into start of 2nd Crack (about CS8-9) for Espresso style, and I always roast Single Origins and blend afterwards.* I often drop Ethiopians a bit earlier than say PNG to retain some fruitiness. For Cold Brew & Syphon etc, I take it roughly mid-way between first crack & second crack (CS7-8), but also always use sight & smell guides as well.
To extend the time between first crack & second crack I start lowering the temp in the ramp up to first crack, and drop the temp down to 30% a little before or at start of first crack, as well as ramp the fan up to 4. Then slowly increase again to 80% once its stopped being exothermic to ensure it does not stall completely, bearing in mind electric elements take a while to respond. For PNGs especially I find if I ramp up to quickly after first crack, I get higher incidences of divots, so take it as slow as practical.
I think I experienced some divots a while back - are they when a 1-2mm part of the shell comes off exposing the inside of the bean?
Yes, think there are other names like craters, but I call them divots.
Crater. Generally due to too much heat from 1st crack to 2nd crack: