First post - love the site, lots of great info and wonderful people. I was using a heatgun flour sifter for a few years with good results, had to do repairs and realized I didnt have time to tinker (Which I loved doing) with the HG setup and spend time with my kids so I purchased a BocaBoca250. Great experience so far, it is a different roaster all together, great for home roasting, great pricepoint and build. Not great for hooking up to an app for replicating the perfect profile but it makes good coffee. There is not a lot of info on the roaster out there, I believe most folks would be happy to go up in price to get more out of their roast but I am happy with the setup. The thermometer setup on the 250 is difficult to read as it rotates and is graduated by 2 degrees C with thicker graduations each 10 degree C. I plan on posting some temp vs time settings, with my best guess at the temp. Hope I can provide info for others that get this unit. Fair warning, I like darker roasts.

Hi, CidCoffee
I'm also one of the happy owners of this roaster. It's definitely does its job but huge minus, as you mentioned is absence of temp readings. I've made some mods so far to use artisan and added some pwm fan to improve drying stage, and I can't imagine how to roast without these features. I've even posted here my solution, but bottom line is that this roaster is good as is and not great candidate for modding.
I'm planning to buy kaldi or some other metal gas roaster to try it on the gas stove.

Regards,
Boris

Boris
Thanks for adding to the discussion - glad to hear about more users out there! I have roasted 4 times with it, so far so good. I log my temp setting and the thermometer reading but the accuracy is a challenge so I use the temperature as an *indicator* that rate of rise continues but I am not very confident that the temp is even accurate. Here are some settings I used, let me know if you think of a better format to share, not positive if folks are interested. I also have pics though cupping is usually more important, but they are very even with no tipping/scorching that I sometimes had with HGFS.

Costa Rican from HappyMug: 150grams Preheat to 150C, setting 10 until 3min then setting 8 until 6min then setting 4. First Crack at 8:30 and end of roast 13 min and came out with a great blueberry taste

Costa Rican from HappyMug (2nd roast): same as above but with 165g, good but no blueberries

Mexican La Laja from CoffeeBeanCorral: 165g preheat 150c, setting 10 until 3 min, then setting 8 until first crack at 8:15 then setting 4 until end of roast at 11:15. Good but not amazing

Mexican La Laja from CBC (2nd roast): Same as above but 170g, have not tried.

I'd be very interested how you setup Artisan and also about your drying phase / fan setup - Thanks!

Hey, CidCoffee
My thermocouple mechanical mod described here
Boca Boca roasters thermocouple mod
Artisan setup is Arduino uno + MAX6675 Module + some multimeter open junction thermocouple. Arduino sending readings via serial port an also has hooked up display module for more convenient usage.
Regarding fan, it's just some Delta high rpm server fan with pwm control pin, that hooked to another Arduino it has some pwm code that generates control impulses at 25khz and setting duty cycle over them to control the fan. I did this control over serial port as well, with some small python tk slider with position digital indication so I have sufficient precsition over the roasts. I'm using only 10 percent of available fan thrust.





My default roast scenario is to preheat to 200, then switch off the heater and wait when it drops to 180, then load 180 gr of beans 30 sec soak at low gas. After switching gas to 11 and control the roast using RoR curve to make smoothest descending rate and avoid peaks. Towards the dry end, approximately at 120-130 C I get some spike in RoR - probably because of beans moisture evaporation, and here my fan is used to get rid of this steam without lowering the gas. After achieving 160 C, I have internal convention that drying phase is finished and I'm starting to lower the fan and lamp, also trying to achieve smoothest RoR.
Drop is usually at 201-207C, dev time after FC is 10-16% of overall roast.
First roasts, especially with analog thermometer were awful, grassy, undrinkable, but somehow I've got it and can't imagine that I'm going to buy already roasted beans
One additional thing that was a bit strange and disappointing is temp control handle that has a click that do nothing at zero position. I've examined it's schematics and fixed this, but it was definitely not a defect and PCB was intentionally designed to make the handle switch out of loop Also from interesting things inside it has additional potentiometer to set triac's gate current, and I've changed it a bit to get smoother control and improve low gas range - it was too strong at minimum setting and at development stage I've got over 210C and was forced to switch it off or drop faster to avoid french roasts Here in Israel we have a bit high voltage of 240v and this roaster was designed for 220v maybe that's the reason...

Regards,
Boris

I am very impressed and need to go through your mods to understand. So cool!
Thanks for sharing!