Iroast-2 resistor hack

-

FOB, a fellow coffee entusiast on the Dutch forum, posted about a fun little hack he did on his tiny Iroast-2 to tame the heater.

 https://www.koffiepraat.nl/forum/viewtopic.php?f=59&t=13359

Below I post an English translation with his pictures:

I recently started trying to roast coffee myself in an I-Roast 2, a small fluid bed burner that can roast a maximum of 150 grams of coffee at a time. This is fun to do and after the first kilogram it is not only drinkable, but also tasty.

But it burns very quickly. And even though the temperature sensor doesn't seem to be very reliable, it does seem to burn hotter than the set temperature. A post from years ago on a forum of our Australian colleagues describes that the power can be reduced by replacing a resistor. I decided to give this a try.

I don't know if there are other forum members with the same roaster because it has been out of the market for a number of years. But I'll describe the process here in case it helps anyone else.

First you open the bottom of the I-Roast, i.e. the round flap that is secured with 3 so-called "spanner" or "snake eyes" screws. I believe these screws are used to discourage opening a device, and I don't have a suitable screwdriver or bit. That's why I improvise one myself by grinding a slot in an old bit.

This makes the bottom open easily. It appears not to be necessary to open the device further, because the resistance is easily accessible in the recess at the bottom in the photo.

You can see that it is a 1kΩ resistor (brown, black, black, brown, brown). Remarkably, this is contained in a JST-XH plug, as if it were intended to be easily replaced. We simply pull this out with pliers.

I don't have any suitable plugs in stock, so I'm going to reuse it. We carefully remove the resistor and the crimp terminals from the plug. And we replace the 1kΩ resistor with one with a slightly higher value. I use a 1.8kΩ (brown, gray, black, brown, brown), from which I cut the wires to size. I solder this into the crimp terminals and plug it back into the plug.

Finally, I push the plug with the new resistor back into the socket and close the bottom.

It now indeed roasts a little more relaxed than before. The settings are the same, but the time to first crack and total roast time are longer, while the roast is lighter. The temperature measured by the sensor does not correspond to reality though, because it appears to be higher than before. Now I'm even more curious about a thermocouple.

Settings:
- 160°C @ 2:30 minutes
- 200°C @ 4:30 minutes
- 234°C @ 5:00 minutes

 








Reacties

Een reactie posten

Populaire posts van deze blog

Tiny Cheap Fluid Bed Roaster by Tije and Jan

-
Afbeelding
(also see Daily Coffee News feature ) Tije designed and made the following structure for a tiny and cheap fluid bed roaster, to which Jan van der Weel added the Arduino parts, electronics and programming: Sketch by Tije de Jong Jan sourced a very cheap blower (€ 11) to start with, Tije developed and constructed the mechanics, Jan built together and programmed the TC4 / SSR electronics.  On his blog, Jan will specify exactly how the TC4 part is combined and programmed and I will copy these details into this blog entry, just as Jan will use this video in his blog. We did a few test roasts to make sure it works at all and it does. Towards the end, the first roast tended to get a flat BT line and airflow was slightly decreased. 200g seems max load of green beans. Second roast a little more power was given to the heater. Next we will try the Background Roast driven by the PID software of Artisan. A week later, with updated software that works better to change the fan
Meer lezen

Finished Pavoni & Fuji PXG4 pid: Probe Inside the Ring

-
Afbeelding
Delicious cup: all the work was well invested! At the end of the previous blog about the pressostat and PID working together , I mentioned that I would like to clean up the xmas tree of wires and have as few cables and probes as possible to visually disturb the classic design of the La Pavoni. Getting rid of the probe that was fastened with copper tape to the top of the brew group was a priority. I wanted to hide a new probe in the cooling fin as close as possible to the brew group. This morning I asked Tije if he could do that. He would need to drill a straight hole of 3mm diameter in the 4mm inner ring of the cooling fin that sits as a tight clamp around the brew group. Always the optimist, Tije set to work: First, Tije made a piece of aluminum to fit the inside of the ring. Drilling a thin hole straight through the curved aluminum, if possible tangentially going through the inside of the ring to touch the brew head directly, you need the support of the temporary insid
Meer lezen

TC4+ boards and Arduino controlled roaster by Matthias Gerstgrasser

-
Afbeelding
illustration by Matthias Gerstgrasser On the mailing list for Artisan users , Matthias Gerstgrasser posted a report about his coffee roaster project, with a link to a beautifully illustrated, complete step by step guide of his work on Instructables: A while ago I posted a few messages on here regarding automation for my hot-air popcorn roaster, and was asked if I could share a writeup of what I had been doing with my setup. I know it’s been a long time, but I haven’t forgotten, just got a little sidetracked (more on that below). I have finally found time to do this over the last few weeks though, and compiled a step-by-step guide of how I modified my popcorn machine. This is now available on Instructables: https://www.instructables.com/id/Arduino-controlled-DIY-Coffee-Roaster/   Do let me know if there’s anything missing or anything that could be improved. I intend to keep updating the guide as I find ways to improve it or as new developments occur. I am also discussing b
Meer lezen