New Firmware V500 released


Could you try doing a normal preheat to see if this also triggers an automatic move to roast mode?
The Bullet was not designed to preheat in the way you are doing it so it could behave in weird unforeseen ways.


I am running through a preheat cycle right now and will post my findings shortly.
Thanks for chiming in.
No heat soak anymore, Roger!


Haha, alright!


Preheat to 250C after 10min.
Charge command after about 30 min. Total run time.
No auto-roast after 60 min. Total run time.


HAL 9000 is my friend again.

Thanks to celticcupcoffee and Jacob for helping out!!


And before I forget it.
The Bullet most definitely needs a HAL 9000 audio option.


The “Charge” command is coming after 30 minutes? That sounds odd from what I’m seeing with my Bullet. I get to a 437F preheat in about 10-12 mins and never wait for the command. If you have reached your preheat setting, don’t wait for the command, start roasting without it. I’ve only heard the “Charge” command once in (7) roasts and would be wasting electricity waiting for it. Go forth and tell Hal (or Miss Aillio) to go back to sleep…:wink:


I like creepy voice commands, but HAL is firmly asleep again.


It’s still a good idea to wait for the charge command if you want consistent roasts. The algorithm looks at the temperature stability of the whole bullet, but just the drum.


Good to know. I was wondering if there was more to it than reaching target temperature.


I roast in my basement which is well within the ambient temps for the Bullet to operate. Is the “algorithm” you mentioned affected by ambient temps that may affect stability, or are you speaking of other things? It would be helpful to understand your point with a bit more information as to why stability would be affected.

I’m not seeing any stability issues by not waiting for the “Charge” statement to be played. The way I see it, if the drum is at temperature and I’m roasting in a stable environment, what purpose is served by waiting for 30 minutes (or whenever the mood strikes) for the “Charge” statement to be issued? That would be a waste of my time and energy cost when the drum is at the ready point for loading beans. What else would I be waiting for after 10-12 minutes has passed and the drum is at temp? I’m just not following why the user would need to wait for “Charge” to be stated given my parameters.

If I were roasting outside of the ambient temps required to properly run the Bullet, then yes I can follow what you are saying. I’ve seen other electric roasters that could only perform properly and produce “stable” results if the environmental temps or the electrical source requirements were met for operating the roaster. Please expand upon your thought so that we all can know what limitations of stability the Bullet may have. Thanks.


The algorithm is also looking at the stability of the bean probe. If you don’t have the IBTS it is also looking at the IR ambient temp which is kinda your front plate temperature.
Basically it is waiting for the bean probe to stabilize too before going to charge.
When we first began this project we also thought that only the drum temperature mattered, but other things like the front plate and maybe the back of the drum also needs to heat up, and this just takes some time as it is only heating indirectly by the hot air.
So you can do you own experiment of letting the bullet preheat to your setpoint and then immediately charge your beans vs waiting until the automatic charge mode. You should see that the later has more energy and the roast will be faster - keeping all parameters the same.


This is excellent information. Thank you, @jacob.

Knowing why a particular feature works the way it does helps to reinforce the use of that feature, as well as bolstering all of our confidence in the roaster and the team that developed it.


Thanks Jacob, the additional information is useful. In my case, I’m having no problem with the speed of the roast. I also adjust the P-level, fan, etc to drive and slow my roasts to reasonable completion times by roasting standards/experience I’ve used for almost 20yrs. I don’t know the operational parameters of the “probes” you are using for the Bullet. In my experience using high quality thermocouples, I’ve never seen them take long to read accurately. I do have a recent Bullet with IBTS (ala the March Sweet Marias" batch). For me, the roaster has the capability of delivering very acceptable results without waiting past when the drum temp has been achieved. Hopefully that won’t change as the roaster ages, but if it does, I’ll have to adapt.