I built a simple assist system for hand-sorting green coffee beans.

A camera looks at the beans spread out on a tray, detects defective ones (black beans, insect-damaged, moldy, etc.), and a projector shines pointers (red dots/circles) directly onto those positions so you can pick them out more easily.

It’s running on a Raspberry Pi 4B. The idea is not full automation, but a helper that reduces the mental load and eye strain of pure manual sorting. I got the idea after seeing a roasted coffee sorter demo at SCAJ and thought something similar could be useful for green beans at a smaller scale.

Currently it only checks one side because the mechanics for flipping or imaging both sides cleanly are a bit tricky to implement right now.

Current status:

　It works “somewhat.” The pointers land roughly in the right places.

　Accuracy is still quite rough (false positives/negatives happen).

　Calibration between the camera and projector is the main pain point.

I’m sharing it mainly to see if anyone finds the approach interesting or has suggestions on improving the detection side (lighting, model, etc.). Happy to hear thoughts or similar projects you’ve seen.

My spouse found the roaster for 15 bucks at a thrift shop. I then discovered I can get green beans at a shop around the corner from my office. I'm quite happy with how my first roast looks.

The only downside is that I have to wait before I grind them up and squeeze hot water through them.

Reading this subreddit before buying my beans made the whole process painless.

Congratulations to 2027 Micro and Macro Roasters of the Year! Both feature stories are free to read here.

New to roasting, but have been a long time coffee nerd. The background here is I got a ‘popper is a coffee roaster’ as a gift. I’ve been trying to roast something ‘decent’ for filter (v60) and it’s been a struggle.

As an FYI, I do not have a temp probe installed on the popper (so I do understand this significantly impacts consistency). I’ve been just tracking the roast phases by sight/smell and noting the time.

This is a Guatemala gesha from Sweet Maria’s. 4 min of drying. 2.5 min of maillard into first crack at 6.5 min. Then 1 minute of development. 12.1% weight loss.

I can’t help but feel like the color is just very uneven and I can’t tell if there’s any scorching. Previous roasts have had decent acidity but harsh bitter/ashy notes. For those roasts I was hitting first crack around 5 min with a very short maillard phase (~1.5 min). So I stretched it out with this batch but I’ll be honest, it looks pretty similar to my other batches. Any thoughts?

I have been home-roasting since February 2022. I initially only would buy wet-hulled coffees, then switched to washed coffees. Today I roasted the last of my washed Oaxaca Mexican coffee and today get in the mail 20# Ethiopia Sidama Durato Bombe Natural. I have always preferred medium roast, and have never roasted naturals. The roaster I am using has adjustable power levels but a fixed fan speed and fixed RPM.

Any tips or reference for roasting Ethiopian Geisha? My first time roasting such a dense coffee from Gesha Village. I used my standard fruity profile that works for most Ethiopian beans but this came out extremely grassy for the first couple of weeks. It’s starting to show some florals and sweetness after tweaking my brew recipe and letting it rest but any experienced roaster out there able to advise?

Should I keep to a similar profile and just wait it out or how should I tweak my roast?

What’s the first thing you’d change about this roast?

Hey everyone! I’m new to roasting and would appreciate some feedback. I’m using a Bideli 2 kg roaster, working with 743 g batches of Colombian coffee, and aiming for a filter roast.

I’m learning how to connect what I see in Artisan with what I taste in the cup.

At 6:00, I increased the airflow setting from 3 to 6. I’m particularly curious about how that adjustment affected the RoR between minutes 6 and 7.

• Would you increase airflow more gradually or at a different point?
• How would you approach gas adjustments before and after first crack?
• What would you look for when cupping these batches to decide what to change next?

I’d love to hear practical suggestions—and what helped you most when you were starting out. If anyone here roasts on a Bideli, I’d especially appreciate your experience. Thanks!

Hi, I’m looking to buy a MacBook Neo, and wondering if Artisan scope work with MacBook Neo?
Does anyone use install Artisan Scope on MacBook Neo and if there is any issues?
Thank you in advance for your replies and enlightenment.

I’m new to the roasting thing. I have a Poppo roaster that I just got from Sweet Maria’s. Today I tried it the second time. I want a light/medium roast (City Roast). I roasted outside at 1200 watts on a 70 degree day. First crack started at 2:30, and I pulled these out just before 4:00, just after the heavy popping stopped. From everything I read this should be a light roast… but it looks very dark to me.

Since I’m a beginner, I’d appreciate any advice as to what I might be doing wrong. So far both batches I’ve made seem to be way darker than I expected, even after I bought a watt meter and took steps to lower the power.

Picture in full sunlight to get an idea of the color:

My Kaleido M2 Lite was delivered nine days ago. I got four roasts on it last Sunday, and two more today. I’m trying to approximate a profile that I would expect to produce good results, but I’m not close.

I’ve roasted on a Behmor 2000AB+ for four years, and produced pretty good results. I plateaued, though, and roasting wasn’t as fun. I’m on a new machine now and there’s a lot to learn!

My understanding of how to start a roast with this type of machine is to charge with sufficient temperature to prevent stalling, and to gradually apply less heat. Increased air late in the roast. So far, I’ve flown through to first crack (my final roast today took 6:30) or stalled the roast.

Am I thinking about this wrong? If not, do you have targets for charge temp? Other milestones you’re trying to hit?

I love the roller coaster of learning. If you have something that’s helped you roast better on this or a similar machine, I’d love to hear about it!

Roasting a Brazilian natural (Fazenda Fronteira, 1350 m, Catuaí / Mundo Novo / Obatã / Bourbon) on a ROEST, 100 g batches. I want to use it as an omni / light espresso coffee.

My last tasted roast was fast: FC at 6:02, drop at 6:50 at 207 °C BT, 48 s development. It had clear peanut notes and basically no acidity.

My new roast is longer: FC at 8:38, drop at 10:00 at 210 °C BT, 1:22 development. It’s still resting.

What do peanut notes usually mean? Should I lengthen the roast even more?

I've been roasting with this corretto setup for a couple of years, and today I finally got it working with artisan, using an Arduino, some ada fruit breakout boards, and some thermocouples. First test today and everything is working, but the ror line is all over the map, and I'm thinking the system is just too noisy. I've got bare bead thermocouples in there now, but I've ordered some in sheaths to replace them and hopefully that solves the problem. I'm also wondering what folks have had luck with in the filters settings for smoothing out noisy curves without losing too much data integrity.

So, I’m not at all new to roasting and I’ve roasted a lot of natural process coffees over the last couple decades. I’m using a Aillio Bullet R2. I also started with a roasting curve that I’ve used for a few different natural or fermented Pacamara varieties. This one has presented a challenge. The mucilage is really stuck on the beans, so while it produces a lot of chaff, it leaves a good amount stuck to the beans, especially on the bottom, which results in the chaff blackening and remaining on the underside of the bean. While all of the characteristic fruit notes are present, it also has a, to me, undesirable smoky taste along with it. Even the second attempt, which was more conservative with the power level and upped the fan speed a bit, had the same issue. Both batches were 500g

Power = P, Fan = F, Drum speed = D

Attempt 1

Charge temp: 473°F

0:00 - 3:50: P8, F3, D8

3:50 - 5:09: P7, F3, D8

5:10 - 6:00: P6, F4, D8

6:01 - 7:47: P6, F5, D8

7:48 - 9:44: P5, F5, D8

End temp: 401.1F

Attempt 2

Charge temp: 464°F

0:00 - 6:10: P7, F4, D9

6:11 - 7:19: P6, F5, D8

7:20 - 9:15: P5, F5, D8

9:15 - 11:06: P4, F5, D8

End temp: 395°F

12.2% loss

Both roasts ended up at 12.2% loss.

Here are pictures of the green beans and the roasted beans. You can see that especially on the bottom of the beans there is a lot of mucilage stuck on. I obviously expect mucilage on natural process coffees, but this one seems extra tenacious.

Anyone have any insight on this and how my approach needs to shift to account for this? I feel as though to avoid the blackening of the chaff and the resulting scorching, I’d need to take the heat down to the point where I’d be looking at a roast time of possibly 15:00 or so.

I purchased 2lb's of Guatemalan green beans from Sweet Maria's and I have been roasting small batches to get a better handle on roasting. I accidentally roasted to second crack (I thought it was first crack...thanks gene cafe for being loud!) and achieved a full city+ roast on accident.

I usually try to achieve a light-medium roast. I do enjoy dark roasts, but most roasters (i have personally tried) always over-roast, leading to a charcoal taste so I usually avoid them.

After three days of rest, my accidental dark roast has become one of my favorite coffees! It's not bitter at all and has a dark chocolate, almond taste and has a nice mouthfeel. It's quite pleasant! I'm definitely going to try and replicate it on the next roast!

and my first roast ever!

My first coffee bean roasting, love it!

Indian Specialty Robusta (From Koraput Odisha) — highly revered in many European countries, yet still misunderstood in its own homeland. This roast was an attempt to bring that potential to life.
Carefully selected, harvested, and cured. The roast profile was curated on the Nucleus LINK, keeping the delicacy of the beans in Mind.
In frame: Naturally processed Koraput Robusta, fruit-fermented for 72 hours.
The aim: To explore the full potential of this nano lot, bringing out its character and complexity.
Roasted with manual brewing in mind, then explored through a wet blend cold brew, and well know Bombón.
Not just a roast, but an exploration of what Indian Robusta can truly become. ☕
#IndianRobusta #SpecialtyCoffee #CoffeeRoasting #NucleusLINK #NanoLot #RobustaCoffee #CoffeeFermentation #ManualBrew #ColdBrew #CoffeeExploration

Hey everyone!

I've recently been experimenting with roasting Nicaragua Moncho Díaz Pacamara Natural beans on ROEST and would love to hear about your experiences with this variety.

I'm still learning and trying to understand how to get the best out of these beans. First crack was almost silent.

A few questions:

• Do you approach Pacamara differently because of its large bean size?
• What kind of roast profile works best for you?

I'm mainly roasting for filter coffee, aiming for a light, fruity, and juicy cup.

100 g in, 86.3 g out

First crack 6:58 at 203.4°C

Drop 8:13 at 208.3°C

Dev time 1:15 (15.2%)

My charts are coming out very choppy and not sure why. Some setting was originally checked after install, but since I've been messing around with it, I could've checked it myself perhaps. Either way, would appreciated if y'all can give me some advise on the setting so that it doesn't end up being choppy.

For the heat source, we have a Bosch gas stovetop, so I use the one that has the fire nearly matching the width of the drum. I've tried not adjusting the heat by turning it down vs. leaving it as is.. and both still end up being choppy. I want it to have enough energy in the beginning so it will carry through the roast, but i'm wondering if perhaps when i have the range hood on high, it may be disrupting it overall? I could try and put a cap or something over it, but not sure if that would help.

In any case, any insight would be helpful. I've attached a photo of the setup in the curves setting as that's the only thing i've adjusted. The sampling is set at 4 sec.

My roaster setup:

Kaldi Mini gas drum roaster, roasting over gas stove top in our kitchen with range hood on high for ventilation

70rpm drum speed, I can modify the speed of drum as needed

Using 1 probe for BT and measuring using Mastech MS6514 and a PC

We are a small coffee shop, thinking about dipping our toes into roasting. I got targeted ads for Bellweather the second I started to research and now their sales team calls me like 15x/day. I have been able to find some info on their equipment on reddit, and I'm scared. Is there anything like them, but better? We like the idea of a small toaster for our shop - it's a drive-thru only so it's small. Anything else out there that isn't "breaking down all the time"?

This is the first time I see a coffee treated with the Swiss Water Process (it is actually the first time I see a decaf at all). It looks already roasted! And it smells very different. I will roast it today.

I am a new owner of a Kaleido M1 Lite. I wanted to be able to run hi bean with my iPad, so I got an ESP32 and successfully flashed it with the correct bin. I noticed the Kaleido board doesn’t have an upper usb port like it did in the pictures in the tutorial. It’s now a 4 pin JST connector. I purchased a JST to USB cable, and connected it all up. Upon powering up some smoke came off my ESP32. Fried. Any ideas? I think I may just seek out an android tablet, I should be able to connect via Bluetooth that way.

Hi everyone
Recently got my bullet and started roasting,
The espresso roasts are going pretty well and I’ve managed to get to pretty good results with the coffee I bought.
The filter roasts though, make me lose my mind.
I feel a bit lost and I’d love for some help!
Currently trying to roast a natural Guji from Hambela
And a washed Yirgacheffe from Chelchele

The Hambela so far gives me cacao nibs despite roasting quite light
The Chelchele is sour and lemony but accompanied with an annoying bitterness.

Tried roasting both of them from 8 min total roast with 1:30 dev time all the way down to 6:30 with 0:50 dev time

We're setting up a tasting room for our roastery. We're going to have a plumbed-in espresso machine, and I'm looking at inline RO and remineralisation. I was wondering if anyone could comment on any of these systems that are working for them or if anyone has any tips for this kind of setup.

Hello Everyone,

I’m a coffee roaster based out of Nashville with a bit of a loaded question:

I roast my coffee in my garage in Nashville and use a lot of sanitary precaution when packing, roasting, etc. Technically, I’m not supposed to sell across state lines. I have a website that sells only coffee beans to people all over the US, and I was wondering the severity of selling dry goods across state lines. Yes, I know I am confessing to a fault, but in my opinion my business is just nowhere near big enough to get a warehouse. Any help would be greatly appreciated.