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Modifying Sweet Mary’s Nostalgia air popper for dummies
Jeff Conti
I am having a significant amount of trouble doing something that seems to me should be easy. Clearly it’s easy for many and darn hard for some (me).

When trying to roast, I was not getting to first crack and I didn’t like the flavor of the coffee. The beans were a stripped looking bean when finished (about 15 min). So, I re-roasted the beans. This doesn’t seem to be a common practice. The coffee flavor is not good but better than what might be called a light (to light for me) roast.

Like many of us here I have been reading and watching YouTube videos. So, I removed the thermostat and connected the two wires. No problem, so far so good. I am cooking with gasoline now. Dried beans in 2 minutes, 1st crack in 4. Finished 1st crack in 6, began second crack about 8:30. Done. I documented everything!!!! I have a Fluke 62 mini IR thermometer and monitored my temperatures and wrote them down including the hot bean just as I dropped them on the basket. Between 415 and 430 deg F

Roasted coffee. Still not very good albeit a little more drinkable. Progress.

There are what you guys call profiles. I take that to mean the ramp up time, soak time on a plotted curve. After 48 documented roasts I succeeded in 2 that we really liked but were not repeatable. Lesson, while elusive, it is possible. My best guess is I need more control (air and heat).
I am not an electronics guy. Unfortunately I fall into more of the dummy category. I don’t really want to play with computers or what Mike (pinned post on modifying the West Bend Poppery) calls a PID. I was a medic in the army and PID stands for something vastly different and unpleasant for women.

Can I insert a switch for the heater and a controller (maybe a dimmer or rheostat) for the fan. It seems like having the heater on intermittently could prolong the drying phase and perhaps the development phase. Controlling the fan might decrease the heat lost and allow for a steeper heat curve.

Similarly perhaps 2 controllers (rheostat?) to manage the fan and heat. Again I’m not an electronics guy.

Perhaps there is a front panel on a project box (use with the PID I suppose and a knob to turn) because I’m not a computer guy.

Guys, I want to keep roasting coffee!!! I would like to learn these control details before I eventually (next year) plunge into a roaster. I think I am stalled.

I did see a guy “Chicago John” on YT and he brought me here but I can’t find his write up which I suspect would be similar to Mike’s.

Any way, I’m not opposed to research, reading, watching and trying. Thank you.
Jeff Conti attached the following image:
The best solution is to use such cheap, but precise voltage regulator on heater:

If the link expires, the search term for such device is: "LED Display SCR Voltage Regulator"

Before roasting perform a scale calibration, to find the power levels for 170-200-240 C temperatures. Then forget about thermometer :)
Start with a preheat in the 170-200 C ballpark, drop the beans, and ramp from there to about 240 C in 4-6 minutes. Let there to the first crack, then watch for the desired development level.

Report back here with a great satisfaction smile :)
Jeff Conti
Walfront SCR Electric Voltage Regulator Dimmer Temperature Controller Motor Speed Controlling Module Board with Cooling Fan (110V AC 4000W

This is what I found for 110 V input albeit no LED Display. Am I getting close?
Nope, pot handling is not precise, nor easily reproducible, please search a digital version.

The 220V units should work for 110V too, voltage is not the limiting factor, but frequency difference could alter the control scale with a factor of 50/60, 100% becoming 84% or something like this.
But linearity and control precision remains unaffected.
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