You all know I mounted a stainless steel mixing bowl in/on an automatic
bread machine so as to have more stirring power in the turbo crazy setup.
I roast outside.
Today it was 66F and quite breezy, which caused the roaster to heat up
slower, but helped blow away the chaff. (and smoke)
When I first put it together (two weeks ago?) I initially did a very
small roast, and next did 1024 Gr. The large batch turned out terrible,
partly because the heat turned off the mixer part way through, and
partly because I had no real way to monitor the temperature.
To remedy this I drilled a quarter inch hole in the SS bowl near the
top, and poked a length of 1/4 inch copper tubing through it, so it was
in the beans, but above the stirrer.
The thermocouple goes in this tube and does not protrude out the end, by
an eighth inch or so.
The reason to hang back is that I found little difference in readings in
whether it did stick out or not;
and because it gets quite noisy when the copper probe contacts the
stirrer, I thought it prudent to keep the TC tucked safely inside :)
Today I decided to start a bit smaller.
With no preheating, the 600 gram batch went to full city in about 25
I preheated and tried 700 grams.. took about the same time.
With 800 grams and preheating to 400F, the time was about 28 minutes to
Vienna roast happened because I had changed the TC position a bit, and I
really should have been paying closer attention.
Forget about hearing first crack with this setup.
I think the fact that it is sealed pretty good blocks all those sounds,
plus it is about as noisy as a... bread maker ;)
The smaller batch I dumped when it was finished, and cooled it by
pouring between my screen colander and a ss bowl.
This can get you burned!
With the other two batches I just cut the heat on the turbo, offset it a
bit, and left the mixer and the fan on.
The beans cooled rapidly like this, and the chaff all blew away.
In two minutes the TC was under 300F and in 4 minutes I was able to
scoop beans out with my bare hands.
Much nicer than dealing with 450F beans and trying to cool them in
When it is not so windy out I will just set my box fan to blow across
the roaster and direct the air inside with the offset turbo, same as in
the wind today :)
So far it heats up too slowly to consider trying much of a profile. I am
thankful it gets to second crack!
Perhaps adding insulation and roasting when it is less windy will speed
up the ramp time.
Will let you know how this melange ( I mixed all three batches together)
tastes in a couple of days.
Roasting coffee with little expense, here in LHC.