I have played with the IR2 trying to get a profile that matches the
slope of a USR roaster I watched in action, and came up with this. In
~13 - 15 minutes, it produces a roast from FC-Vienna. Is it
repeatable? On my machine, yes. Your IR2 may (WILL) vary.
First, the basics.
My thermocouple is accurate to +/- 1 c or ~1.8 f
My scale is accurate to 1 gram
All values are for 148 grams of green beans at Start of Roast
The thermocouple is seated 1/3 of the green bean mass from the bottom of
There is a 4" dryer vent attached to my IR2.
No loosening and /or removing the chaff screen is required.
For 3 roasts with ambient temperatures of 76, 77 and 78f, here is the chart.
Roast 1 was cut at 446 f. Roast 2 was cut at 454, and roast 3 at 448 f.
Roasted weight for these in order, is 127 grams, 126 grams and 126 grams
Profile in IR2 is:
3 minutes at 320, 4 minutes at 335, 2 minutes at 350, 3 minutes at 365
and 3 minutes at 390.http://www.onlymysite.net/files/Profile6.xls(I hope this works...it was done in OpenOffice and saved in .xls format)
Please note that dropping stage 5 to 385 will NOT give you the expected
results, at least on my unit. I thought it would allow me to use the
final 1 to 2 minutes of the roast to get to 454. Instead, it peaked at
436-438 at 15 minutes...but that is an almost perfect FC, at least how I
look at it, so it too is a useful profile.
Anyway, I hope this helps some of you who do not have PID's attached and
still have working smoke alarms in your house. ;-)
PS... If any of you folks who have experience in charting profiles would
care to comment on the slopetime ranges, etc., I would be very
interested in hearing your observations.
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20