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02/23/2019 9:17 AM
Ethiopian natural Gesha today .. tasting it tomorrow.

02/13/2019 4:49 AM
Thanks again Ginny.

02/12/2019 3:29 AM
Good morning all. Just finished a few days with Yemen Red Harraz. We liked it.

02/11/2019 10:05 AM
probe diameter

02/11/2019 10:01 AM
probe dimension

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Poor TC placement- Drum (solid)
I'm almost finished making a solid (not perforated) drum roaster and due to the shape of the drum (see here for pictures) I cannot get the thermocouple (in a 18cm/7in sheath ) to actually touch the beans, instead it is just measuring the air temp inside the drum. Which leads me to my question, how will the temperature that I am measuring relate to the temp. of the beans? I haven't started roasting yet (variac problems), but at a constant 220V for 7+ minutes the temp in the drum gets up to 150C/300F. I put in a handful of beans and at this temperature I heard first crack at about 4.5 minutes. (I took them out a minute or two later, they were dark but hadn't reached second crack). Is there anybody who is measuring the temperature the same way and can give me some advice about this? Thanks
Edited by NetriX on 01/15/2019 3:44 PM
Welcome to the Forum! Welcome

I do not see any photos though.
With or without pictures, bringing into FC in 4-5 minutes with only 150C ET is weird science...
Could be many explanations, I would measure the drum surface temperature too, also let it preheat longer, at least 30 minutes, and also specify the rotation speed.
The most critical measurement on any roaster is bean temp. Seeing bean temp rate of rise is of utmost importance and without it, we're flying blind.

Most small drum roasters are a big challenge in finding a good bean temperature probe location due to all of the rotating obstacles. One method many of us use is to insert the thermocouple into as small as possible diameter sheath that's been bent to 90 degrees. The sheath stays in between the front plate and the rotating forward and reverse vanes with at least 3/8" between sheath and front plate and vanes to prevent lodging beans in between those parts. Locate the sheath tip so it resides in the bean mass about 45 degrees into the upward bean travel with bottom being 0 degrees. Its important to have at least 2" of sheath in the drum to prevent false readings from front plate to sheath conduction.
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
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