Haha great questions Hayley, yeah I acknowledge the thermocouple placement isn’t perfect for getting actual bean temp. So I’m calibrating based off some roasting signals like smell and “first crack” timing. Seems like it reads about 30C less than the real temp. As for Artisan that is the next project! Have to figure out the serial communication protocol from Artisan to my Arduino.
@@BenjaminEagan Many drying processes (spray drying etc.) rely on the exhaust temperature of the air to measure product drying stage. As moisture is reduced, evaporative cooling slows down (exhaust air stream begins to get hotter) and you can work that into the control system. Correlate your knowledge of "first crack" with the observed temperature profile in a known airflow regime (leave that yellow lid on) and...
@@LateralThinkerer This actually explains the anomaly where early in the roast the temp seems to lag more than heat changes in the later stages. I wondered if it was the thermocouple coming fully up to temp, but it's clear now this is most likely moisture being gone. Did you have more to add though? Your comment ends mid-sentence.... Or maybe it's just self-evident that mapping to checkpoints like first crack in a consistent airflow regime can still lead to precise control.
Hey man! Great video! When i lived in Ottawa, Equator was one of my go to roasters :) Coffee mods and what not are always in need on youtube so keep it up!
@@BenjaminEagan honestly, i could've sat through way more haha. I've been wanting to do something similar with my own air popper at home tbh but just didn't really know where to you start (don't have much of an electrical background sadly, but wanting to learn). Was thinking i could do a voltage regulator via light dimming switch to regulate heat and have a separate on off switch for the fan. Then just have a probe from the drum direct to my laptop into artisan to track the profile. Thoughts?
I appreciate that a lot! If you’re feeling overwhelmed by the electronics aspect, I honestly think a dimmer switch and a handheld IR thermometer would be a great first step. Then you can hold a roast profile while keeping it old school with a stopwatch and dial. If that’s feeling good and you want to get more control, then you can dive into the thermistor and Artisan hookup. It’s honestly a fairly tricky first electronics project too, so you might want to get an RPi or Arduino and try some low voltage blinky light type projects simultaneously! Good luck!
Very impressive and I am amazed at how well it works and how good the coffee is!!!! However, I do not agree that you should not put the horse before the cart (@1:14) it is arguably one of the best case horse/cart configurations.
hot air popper popcorn marker hot air popper popcorn maker hot air popper popcorn maker for perfect popping potential opposed to your placid pandemic portioned purgatory potato pot-roasts
Thanks! I missed “profile” at first and thought this was a funny diss at how janky the whole setup looks. I myself am super surprised it holds temp as steady as it does.
Ben, thanks What we really need is a _detailed_ video or Web site teaching us how to modify an inexpensive popcorn machine inexpensively (sans Arduino) so that we can get on with home roasting. With a simple heat control; overheat sensor bypassed; fan always on. Any recommendations?
lol, Really cool work. This was hilarious and amazing. I'm pretty sure this might have time traveling applications as well. @3:33 it totally reminds me of Homers toaster in the Halloween specials.
Great! This is what I have in mind to build -- ideally adding PID either to a gradual rise over time in the formula, or several stages like you have. I don't like the idea of having to cart a computer to roast my coffee (ie Artisan), and you proved it works. I suppose you could add some manual over-ride with a screen for temp and a push button. First things first :)
What did you do with the wire carrying 24 volts ac from the heater that originally went to the bridge rectifier on the fan motor? You would not need this since you were now getting the 24 volts for the fan from the transformer that you added.
This is brilliant! You've taken out the need of a tc4 which everywhere else used! Have you thought of doing something similar with a heat gun and bread maker? Could make it so the heatgun is into a plug and completely removable... Would be keen on your thought on this. Hopefully you can get it to work with artisan software! That'd be a game changer
Thank you! Yeah I went a little off the charts when I couldn't find a TC4, and then it actually worked pretty easily. I was sure the whole temperature system control would need to be more sophisticated, so it's a pleasant surprise. I think the heatgun and bread maker combo would work with exactly the same arduino sketch. May need an extra relay if you want to toggle both fan and heat gun. I've been too lazy to make any artisan progress too, as this roaster has been working too well as is and I'm not sure it would give me much benefit beyond a much much nicer UI!
@@BenjaminEagan Thanks for you quick respone, will have to have a go at doing this with popcorn a maker! Do you change your hold temp rates often for different beans? I think your code has 150c for 9min and then 200c for 4min. Or can this be altered during the roast if the cra ks aren't happening?
Ben, thanks so much for the tutorial online AND this video! Quick Q, about how much beans are you using? I'm attempting the same thing and the fan running full speed sends 1/2 cup of beans right out of the chute, over agitating the beans, and making it harder to heat the chamber, I presume. More beans helps but the center of the chamber still "pops" beans up. Do I need to install a potentiometer and turn the fan speed down a bit? Install a glass tube chamber with a smaller opening to restrict flow? P.S. Artisan can communicate with your arduino over modbus! You can even install a blue tooth or wifi module and run artisan "remotely"!
Very cool about Artisan! I enjoyed solving my own temp control as a test, but always planned to figure out something with Artisan. Full disclosure- this roaster died on me about 6 months ago, the thermistor readings were just going all over the map. I’m sure one of the components is malfunctioning (likely due to heat), but I haven’t solved that yet. When it comes to quantity though, I would advise just adding more beans until there is a gentle mixing going on. As they roast they get lighter too, so the mixing gets more dramatic as the roast continues. Then I’d just make sure you can get that volume of beans up to the target temps. If adding more beans doesn’t do the trick, then looking at a potentiometer for fan speed seems like the right move!
Hi Ben, that looks like a really elegent way modify the roaster and control the roasting profile. Can you elaborate on the connection of the max31855 to the UNO board. Is it just the three Max31855 pins (DO, CS and CL) connecting to the UNO digital pins (7, 6 and 5 repectively)? What about the 3.3 V and GND pins on the max31855 - do these need to be connected to the respective UNO pins. I couldn't make that out on the video or get clarification from your detiled instructions.
OK scratch that - I have connected the Vin and GND pins of the max31855 to the 3.3V and GND pins of the UNO R3 board....and adjusted to the correct baud (115200) so now I'm getting actual text out via the seriel monitor. Unfortunately that text is something like: stat: 0 internal: 0.000 temperature: 0.000 ....endlessly! I have checked all connections (many times) and can't see a problem. Any ideas? Any idea where to seek additional help?
That is frustrating, which thermocouple are you using? I wonder if trying a few different Arduino max31855 libraries might do the trick. Are you trying boiling and ice water to get some swing? Are you sure the connections are all good?
@@BenjaminEagan Hi again Ben, thanks for your response. I have tried different arduino max31855 libraries (e.g., serielthermocouple - from Adafruit Thermocouple Sensor w/MAX31855K) but have the same consistent 0 C temp readings. I've checked and confirmed electrical continuity (with multimeter) between arduino UNO R3 and max31855K breakout board - so that's OK. Power supply to breakout board confirmed at 3.3 V DC. I've moved the TC between ice/water and hot water baths -and can observe voltage change between the TC terminals (-0.5 V for ice water and +0.9 V for hot water)...so that seems functional. I have no idea how to confirm that there is a correct functional output from the max31855 board (from the DO pin i would assume). I'm getting (or is that past tense?) out of my depth
Can you tell me how much power is roughly used in the warm up phase and through the drying phase? Is it anything below 50% total power of the popcorn maker?
Warmup is 100% but I don’t have numbers of a % when chasing a temp target. My gut says something like 30-60%. You trying to match a dimmer to these profiles?
i want to do this, but the power here in australia is slightly diffferent, do you have a wiring diagram for this or do i need to shoot blind? love your work mate
Hi Ben, last question... Have you thought about putting the option of a third roast temp to say go to 225-230c for say 40seconds to a minute for a second crack? My DC converter arrived and is installed. You are right they are big lol! Is there an easy way to get in contact with you if i run into any problems or have any other questions, be keen to share my finished prohect with ya.
Thats awesome @Dane Tombleson, I’d love to see the results! I’m into the lighter roasts so never pushed the second crack that high, but it would be super simple to modify the arduino sketch. I also made a sketch that is just one temp, and use that for the first batch for a new bean and to experiment so you might find that helpful too. Keep in mind this measures the exhaust temp too, so I think it’s actually about 20-30C cooler than what the beans are really feeling (my FC hits at 130-150ish often). So 220 is pretty hot on this rig. I’m pretty responsive here too, so just @ me on this thread and I’ll check back for updates!
About $150 CAD. So not much cheaper than buying a dedicated little hot air roaster. But definitely more educational, and if you can find a used popcorn machine that cuts down price a lot too.
Let's say I needed a bigger roaster... would you prefer I spend money to get a pre-made one like the Behmore 2000ab? Or build another monstrosity possibly involving a barrel, BBQ, and a bicycle wheel?
@@BenjaminEagan Definitely stick with fluid-bed based! I think I read somewhere that this method proved to have the most even roasting. The biggest challenge is trying to get off-the shelf parts to fit everything together and the high operating temperatures. Good luck and hope you make more videos on this, because I just subscribed :)
This is cool :) I've been roasting with a single popper but not controlled. I got a second one so I could up my volume but have discovered the hard way that the two machines of the same model, run at different temperatures :( Worried I just wasted 300gm's of beans because I mixed them together. Ground a handful for a sniff test and Smells a bit grassy :( , hoping after the beans rest for a few days they might smell normal.
Nooo the dreaded grass! What kind of popper are you using? Volume is definitely the problem with these. I’m eyeing some heat gun methods for murder Hornet 2.0, or maybe propane and a rotisserie.
@@BenjaminEagan Using a Breville Crazy Popper. They never trip their heat cutoffs, I have a cheaper no name popper but it runs so hot it gets oil on the beans by 5 minutes and then overheats and cuts out. I don't think the breville ones are hot enough to bring out oil or get second crack. Been roasting for 11 minutes 30 sec, but the second one isn't hot enough to roast to the same level, after 23 minutes, still lighter and slight shriveled weird look on the beans.
Yeah, I find anything over around 15 minutes and you get a very bland flat taste to the coffee even if it looks great. I tried with the west bend stir crazy and it just took too long. Do you use a long extension cord by any chance though on those slow roasts? Shorter cord can help.
Hmmm, yeah both on the mulitbox off a single extension cord. I'll run a check with a power meter to see if there is a difference. But thankfully, it's a lighter roast but seems after sitting for a day the coffee is OK if a bit subpar. I have a have a high temperature thermometer coming in the mail so should be able to compare the temps directly before trying again.
The public domain can have this gift in all its glory! but I'm already thinking of the next one though, and it will almost definitely involve a wood fired steam engine.
looks good, but why didn’t you use the Artisan PID logic, and doesn’t the thermocouple in the exhaust give an inaccurate temp reading?
Haha great questions Hayley, yeah I acknowledge the thermocouple placement isn’t perfect for getting actual bean temp. So I’m calibrating based off some roasting signals like smell and “first crack” timing. Seems like it reads about 30C less than the real temp.
As for Artisan that is the next project! Have to figure out the serial communication protocol from Artisan to my Arduino.
@@BenjaminEagan Many drying processes (spray drying etc.) rely on the exhaust temperature of the air to measure product drying stage. As moisture is reduced, evaporative cooling slows down (exhaust air stream begins to get hotter) and you can work that into the control system. Correlate your knowledge of "first crack" with the observed temperature profile in a known airflow regime (leave that yellow lid on) and...
@@LateralThinkerer This actually explains the anomaly where early in the roast the temp seems to lag more than heat changes in the later stages. I wondered if it was the thermocouple coming fully up to temp, but it's clear now this is most likely moisture being gone. Did you have more to add though? Your comment ends mid-sentence.... Or maybe it's just self-evident that mapping to checkpoints like first crack in a consistent airflow regime can still lead to precise control.
Too cool - great job Ben!
Hey Grey, thanks man!
Awesome job Ben!
Thank you Karan!
Wow amazing idea, need to ask you more for the prototype
Hey man! Great video! When i lived in Ottawa, Equator was one of my go to roasters :) Coffee mods and what not are always in need on youtube so keep it up!
Yessss! Some equator love! Really appreciate the comment, and that you stuck it out even for the shout outs.
@@BenjaminEagan honestly, i could've sat through way more haha. I've been wanting to do something similar with my own air popper at home tbh but just didn't really know where to you start (don't have much of an electrical background sadly, but wanting to learn). Was thinking i could do a voltage regulator via light dimming switch to regulate heat and have a separate on off switch for the fan. Then just have a probe from the drum direct to my laptop into artisan to track the profile. Thoughts?
I appreciate that a lot! If you’re feeling overwhelmed by the electronics aspect, I honestly think a dimmer switch and a handheld IR thermometer would be a great first step. Then you can hold a roast profile while keeping it old school with a stopwatch and dial. If that’s feeling good and you want to get more control, then you can dive into the thermistor and Artisan hookup. It’s honestly a fairly
tricky first electronics project too, so you might want to get an RPi or Arduino and try some low voltage blinky light type
projects simultaneously!
Good luck!
Very impressive and I am amazed at how well it works and how good the coffee is!!!! However, I do not agree that you should not put the horse before the cart (@1:14) it is arguably one of the best case horse/cart configurations.
I guess you still have more to teach me, like the standard configurations of the Horse and Cart
hot air popper popcorn marker hot air popper popcorn maker hot air popper popcorn maker for perfect popping potential opposed to your placid pandemic portioned purgatory potato pot-roasts
please plainly punctuate ponderings proposed pertaining to prescient popcorn pot-roasts
looks really nice profile, almost like professional coffee roaster.
Thanks! I missed “profile” at first and thought this was a funny diss at how janky the whole setup looks. I myself am super surprised it holds temp as steady as it does.
ice job! Would also be cool if you 3d-printed an hood adapter to catch all the chaffs .
Ben, thanks What we really need is a _detailed_ video or Web site teaching us how to modify an inexpensive popcorn machine inexpensively (sans Arduino) so that we can get on with home roasting. With a simple heat control; overheat sensor bypassed; fan always on. Any recommendations?
lol, Really cool work. This was hilarious and amazing. I'm pretty sure this might have time traveling applications as well. @3:33 it totally reminds me of Homers toaster in the Halloween specials.
I've been noticing the dial of my watch slowly runs backwards when I stand too close to the roaster... I think this explains it!
Great! This is what I have in mind to build -- ideally adding PID either to a gradual rise over time in the formula, or several stages like you have. I don't like the idea of having to cart a computer to roast my coffee (ie Artisan), and you proved it works. I suppose you could add some manual over-ride with a screen for temp and a push button. First things first :)
So how did you power your Arduino?
Laptop USB
wow, really nice, but unfortunately i don't have the experience to build like it, I was looking for something not costly for home roast.
I love this. The Murder Hornet! You should trademark that :)
Trademark and Patent Pending!
What did you do with the wire carrying 24 volts ac from the heater that originally went to the bridge rectifier on the fan motor? You would not need this since you were now getting the 24 volts for the fan from the transformer that you added.
That's right, since that 24v wasn't needed I just wired both outputs downstream of the heating element back to ground.
This is brilliant! You've taken out the need of a tc4 which everywhere else used! Have you thought of doing something similar with a heat gun and bread maker? Could make it so the heatgun is into a plug and completely removable... Would be keen on your thought on this.
Hopefully you can get it to work with artisan software! That'd be a game changer
Thank you! Yeah I went a little off the charts when I couldn't find a TC4, and then it actually worked pretty easily. I was sure the whole temperature system control would need to be more sophisticated, so it's a pleasant surprise.
I think the heatgun and bread maker combo would work with exactly the same arduino sketch. May need an extra relay if you want to toggle both fan and heat gun.
I've been too lazy to make any artisan progress too, as this roaster has been working too well as is and I'm not sure it would give me much benefit beyond a much much nicer UI!
@@BenjaminEagan Thanks for you quick respone, will have to have a go at doing this with popcorn a maker! Do you change your hold temp rates often for different beans? I think your code has 150c for 9min and then 200c for 4min. Or can this be altered during the roast if the cra ks aren't happening?
Ben, thanks so much for the tutorial online AND this video! Quick Q, about how much beans are you using? I'm attempting the same thing and the fan running full speed sends 1/2 cup of beans right out of the chute, over agitating the beans, and making it harder to heat the chamber, I presume. More beans helps but the center of the chamber still "pops" beans up. Do I need to install a potentiometer and turn the fan speed down a bit? Install a glass tube chamber with a smaller opening to restrict flow? P.S. Artisan can communicate with your arduino over modbus! You can even install a blue tooth or wifi module and run artisan "remotely"!
Very cool about Artisan! I enjoyed solving my own temp control as a test, but always planned to figure out something with Artisan. Full disclosure- this roaster died on me about 6 months ago, the thermistor readings were just going all
over the map. I’m sure one of the components is malfunctioning (likely due to heat), but I haven’t solved that yet.
When it comes to quantity though, I would advise just adding more beans until there is a gentle mixing going on. As they roast they get lighter too, so the mixing gets more dramatic as the roast continues. Then I’d just make sure you can get that volume of beans up to the target temps. If adding more beans doesn’t do the trick, then looking at a potentiometer for fan speed seems like the right move!
Hi Ben, that looks like a really elegent way modify the roaster and control the roasting profile.
Can you elaborate on the connection of the max31855 to the UNO board. Is it just the three Max31855 pins (DO, CS and CL) connecting to the UNO digital pins (7, 6 and 5 repectively)? What about the 3.3 V and GND pins on the max31855 - do these need to be connected to the respective UNO pins. I couldn't make that out on the video or get clarification from your detiled instructions.
OK scratch that - I have connected the Vin and GND pins of the max31855 to the 3.3V and GND pins of the UNO R3 board....and adjusted to the correct baud (115200) so now I'm getting actual text out via the seriel monitor. Unfortunately that text is something like:
stat: 0
internal: 0.000
temperature: 0.000
....endlessly!
I have checked all connections (many times) and can't see a problem.
Any ideas? Any idea where to seek additional help?
That is frustrating, which thermocouple are you using? I wonder if trying a few different Arduino max31855 libraries might do the trick. Are you trying boiling and ice water to get some swing? Are you sure the connections are all good?
@@BenjaminEagan Hi again Ben, thanks for your response.
I have tried different arduino max31855 libraries (e.g., serielthermocouple - from Adafruit Thermocouple Sensor w/MAX31855K) but have the same consistent 0 C temp readings. I've checked and confirmed electrical continuity (with multimeter) between arduino UNO R3 and max31855K breakout board - so that's OK. Power supply to breakout board confirmed at 3.3 V DC. I've moved the TC between ice/water and hot water baths -and can observe voltage change between the TC terminals (-0.5 V for ice water and +0.9 V for hot water)...so that seems functional. I have no idea how to confirm that there is a correct functional output from the max31855 board (from the DO pin i would assume). I'm getting (or is that past tense?) out of my depth
ooopps, those TC voltages units were mV, not V
how many grams of green beans for single roast?
Can you tell me how much power is roughly used in the warm up phase and through the drying phase? Is it anything below 50% total power of the popcorn maker?
Warmup is 100% but I don’t have numbers of a % when chasing a temp target. My gut says something like 30-60%. You trying to match a dimmer to these profiles?
i want to do this, but the power here in australia is slightly diffferent, do you have a wiring diagram for this or do i need to shoot blind? love your work mate
I appreciate that! I don’t know Aussie power, but if it’s
@@BenjaminEagan thanks mate, appreciate the reply
Hi Ben, last question... Have you thought about putting the option of a third roast temp to say go to 225-230c for say 40seconds to a minute for a second crack?
My DC converter arrived and is installed. You are right they are big lol!
Is there an easy way to get in contact with you if i run into any problems or have any other questions, be keen to share my finished prohect with ya.
Thats awesome @Dane Tombleson, I’d love to see the results!
I’m into the lighter roasts so never pushed the second crack that high, but it would be super simple to modify the arduino sketch. I also made a sketch that is just one temp, and use that for the first batch for a new bean and to experiment so you might find that helpful too. Keep in mind this measures the exhaust temp too, so I think it’s actually about 20-30C cooler than what the beans are really feeling (my FC hits at 130-150ish often). So 220 is pretty hot on this rig.
I’m pretty responsive here too, so just @ me on this thread and I’ll check back for updates!
cool, how much did the whole setup cost?
About $150 CAD. So not much cheaper than buying a dedicated little hot air roaster. But definitely more educational, and if you can find a used popcorn machine that cuts down price a lot too.
Let's say I needed a bigger roaster... would you prefer I spend money to get a pre-made one like the Behmore 2000ab? Or build another monstrosity possibly involving a barrel, BBQ, and a bicycle wheel?
@@BenjaminEagan is this a trick question? 😏
@@BenjaminEagan Definitely stick with fluid-bed based! I think I read somewhere that this method proved to have the most even roasting. The biggest challenge is trying to get off-the shelf parts to fit everything together and the high operating temperatures. Good luck and hope you make more videos on this, because I just subscribed :)
This is cool :) I've been roasting with a single popper but not controlled. I got a second one so I could up my volume but have discovered the hard way that the two machines of the same model, run at different temperatures :( Worried I just wasted 300gm's of beans because I mixed them together. Ground a handful for a sniff test and Smells a bit grassy :( , hoping after the beans rest for a few days they might smell normal.
Nooo the dreaded grass! What kind of popper are you using? Volume is definitely the problem with these. I’m eyeing some heat gun methods for murder Hornet 2.0, or maybe propane and a rotisserie.
@@BenjaminEagan Using a Breville Crazy Popper. They never trip their heat cutoffs, I have a cheaper no name popper but it runs so hot it gets oil on the beans by 5 minutes and then overheats and cuts out. I don't think the breville ones are hot enough to bring out oil or get second crack. Been roasting for 11 minutes 30 sec, but the second one isn't hot enough to roast to the same level, after 23 minutes, still lighter and slight shriveled weird look on the beans.
Actually yeah, am thinking of making my own using gas.... That would be way cool and fun.
Yeah, I find anything over around 15 minutes and you get a very bland flat taste to the coffee even if it looks great. I tried with the west bend stir crazy and it just took too long. Do you use a long extension cord by any chance though on those slow roasts? Shorter cord can help.
Hmmm, yeah both on the mulitbox off a single extension cord. I'll run a check with a power meter to see if there is a difference. But thankfully, it's a lighter roast but seems after sitting for a day the coffee is OK if a bit subpar. I have a have a high temperature thermometer coming in the mail so should be able to compare the temps directly before trying again.
Whhhhoooooa!!
Thanks! And I'll re-emphasize - tell me what country of origin you and Joe like your beans, and I'll roast and send you guys some.
patent pending?
The public domain can have this gift in all its glory! but I'm already thinking of the next one though, and it will almost definitely involve a wood fired steam engine.
the easy way i do it out side, i do it by color not by time . i use a pan to water to cool the beans.
let dry and de= gas wheelchair larry