After debating how I'm going to start home roasting (hot air popper, SR500, Huky 500, or a sample roaster), I've decided on starting small to see what I like, with a hot air popper. I came across an original West Bend Poppery. My original intent was to modify it, using a microcontroller dev kit I have laying around with a triac to control the heating element, and a pwm dc fan. After looking at the poppery, I saw it has a 120VAC fan. So, I'm debating about the best way to control the fan. I've heard there can be some issues using a triac with an inductive motor (would need a snubber, but I see ST has some "snubberless" parts), but most of the issues sounds like it creates a bit of a hum (which I suppose isn't a big deal). I've read that some people use off the shelf variable speed controllers, this one seems popular (http://www.amazon.com/Hydrobuilder-HBVF ... B00BLOSG7I). Has anyone opened one of these up? Is it just a rheostat with a triac, or a very small variac (this one seems doubtful)? I'm guessing it's just a rheostat controlling a triac, given the size and cost of the thing. My goal is to build a small box containing the electronics and knobs to interface with the poppery. Does anyone have any comments on the control of the AC heater and fan elements for this unit?

I've been thinking about making my own thermocouple interface with a couple max31855's (https://www.maximintegrated.com/en/prod ... l#popuppdf) to interface with the microcontroller. However, in the interest of time, I may just end up purchasing a yocto thermocouple for use with the project as that one is fairly inexpensive as is supported in artisan.

The last thing I'm pondering is methods for chaff collecting. Maybe just a simple hose connected to a tin can chimney?

I had thought about just being lazy and getting a SR500. However, I didn't like the fact that the SR500 only has 3 settings for heat.

Please let me know if you guys have any thoughts on the project. Thanks!!

cronus10 wrote:I've read that some people use off the shelf variable speed controllers, this one seems popular (http://www.amazon.com/Hydrobuilder-HBVF ... B00BLOSG7I). Has anyone opened one of these up? Is it just a rheostat with a triac, or a very small variac (this one seems doubtful)?

No experience with the Hydrobuilder, but the Harbor Freight unitis the former. The triac gave me fits when trying to run a watt meter off it.

The last thing I'm pondering is methods for chaff collecting. Maybe just a simple hose connected to a tin can chimney?[x]
I tried a number of solutions, and eventually just let it go up the chimney and out the vent. Not completely successful.

I get very good results with my PID controlled P1. I download the profiles from a laptop, interfacing via a USB - RJ45 interface. Since everything is AC current that makes the modifications a little easier.

Regarding placement of the MET thermocouple, I tried putting it on of of the vanes entering the chamber, but found that the temperature varies widely around the periphery of the chamber as much as 40-50 degrees F. I finally settled on creating a false bottom of stainless mesh, which keeps the beans suspended above the bottom of the chamber, and gives me a place where the thermocouple measures the air reaching the beans. I threaded the thermocouple through the mesh and with the tip sticking down below it slightly. The BT thermocouple is simply suspended above the bean mass on a strip of sheet metal draped over the edge of the chimney.

Speaking of chimney, I used a Bake-A-Round Duo Pyrex glass chimney. They can be found on eBay occasionally. Fits the throat of the poppery's metal chamber perfectly. I had a mounting bracket custom made by a welder friend. See this post on CG.

JB-Weld is your friend. food safe and withstands high temperatures. I used it to secure the thermocouples and other areas where I need to "glue" things together.

See my extensive thread about the development of my roaster controller on CG. If I was redoing it now, I might go with Artisan as a controller rather than the PID.

Matt,

I also started on a Poppery 1 and all I did was wire the fan to always run and have the power switch cycle the heating element. Why not start there and see if its your thing before jumping in whole hog? Hand surfing your first 10+ roasts will be educational.

Can't speak towards your mods, but a couple of random things:

- check that the fan controller from amazon can handle the power draw. I've only heard of people using router speed controllers for this sort of thing, which i suspect are meant for much higher power draws than typical fans. More inline with what a Poppery 1 burns.

- I wouldn't worry about a humming component with a Poppery. The fan is pretty loud already.

Actually, the Poppery is probably the most used and modified piece of equipment on the planet for first time home roaster. I suspect if you did a few internet searches you can find a dozen different ways someone else has already tried for anything you could dream of doing with one. That was also my first roaster 15 years ago and their were tons of them being used and modified then. They are probably what led the way for so many companies getting into the home, air roaster market.

I like the thought of just the simple rewire so the fan is always on, and control the heating element by hand with the switch as a first step. That would get me up and running quick and I'd just need a thermocouple, or even a simple thermometer. It'll probably be awhile before I find the time for the triac controller.

Cheers