Originally posted by noelpolar 6 or 7 years ago I moved from pop corn makers to a full bespoke mobile roasting centre....... can roast up to 800gms or so at a time (a bit under 2lbs).
This impressive engineered machine consists of............ a cleaners trolley, bread maker, hot air gun and an old duct fan (... a full bespoke mobile roasting centre sounds so much better doesn't it?)
Anyway.... the hot air gun temp can be set digitally..... 540 to 580c seems to work best (cold days to warm days)..... the bread machine is only used to stir the beans (I made a metal paddle for it.... plastic ones do what plastic does at 500c).... once beans are done.... drop them into a metal colander and cool in front of duct fan. The duct fan sucks the acrid smoke and the chaff during roasting and presents it to your neighbours (I do all this in the driveway).... one can wait for favourable wind conditions to target "select" neighbours. Generally.... no point being a bit quirky without being a bit evil from time to time.
Like you.... I roast by sight and sound.... two batches each time.... a blend for me and a decaf for wife.... only ever stuffed up one batch when I got distracted.
My father-in-law passed away last month, and when going through his house we found an old Toastmaster Bread Box bread maker. I took it, remembering that you had come up with a pretty slick coffee roasting setup using a bread machine.
Well... the first trial didn't go so well. I mounted a heat gun on an old drill press rig so that it can be positioned over the bread machine. Took the lid off the bread machine, turned it on dough knead mode so the paddle operates continuously. Put in some green coffee beans. Seemed to be going fine until the temperature of the beans reached about 350-375 by my infrared thermometer. That's when the bread machine display switched to a high temperature error message. I thought that was strange, it is a bread maker, so I figured 400+ degree (F) temperatures were no big deal. But maybe in knead mode it monitors to make sure it's not too hot?
In any case, it stays in this overtemp mode and won't stir the beans. So I stirred them with a big wooden spoon until they were done, just so I wouldn't ruin the batch. But unless I can figure a way to bypass the temperature sensor this is looking like it won't work. Oh well, I still have the popcorn popper which works well enough.