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Topic: Thermocouple with HG/DB - was +RK Drum Observations (6 msgs / 137 lines)
1) From: Brian Kamnetz
Hi,
I roast with a heat gun. I put the greens into a sieve, and that fits into a
stainless steel mixing bowl. I have been interested in tracking roasting
temps with Tom's digital thermometer with thermocouple wire probe, but was
thinking I would have to put the heat sampling device into the beans
somehow. I am no engineer and couldn't envision how to do that and still be
able to stir the beans during the roast. I see in the RK drum thread that
the end of the probe isn't in the drum, but an inch away outside of the
drum. I was wondering if I could effectively use the digital thermometer
with thermocouple wire probe by placing the probe in the space between the
stainless steel bowl and the sieve.
What do you think?
Thanks,
Brian
*Digital Thermometer *with a thermocouple wire probe
On 3/24/07, Bob  wrote:
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2) From: Dave
If you use a sieve inside the bowl, couldn't you stick the tip of the probe
up through the bottom of the sieve? Seems like it ought to work. It wouldn't
have to be in very far.
-- 
Dave
Some days...
It's just not worth chewing through the leather straps
On 3/24/07, Brian Kamnetz  wrote:
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3) From: Ken Mary
There are plenty of cheap infrared thermometers on the market now. Make a 
holder or stand so that it can be aimed at the beans but far enough away so
that it is not affected by the heat. This one has a flexible shaft:http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber”233--
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4) From: Brian Kamnetz
On 3/24/07, Dave  wrote:
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I'm still wondering whether a) that would interfere with stirring, and b) if
stirring would damage the probe that  is sticking into the beams. (I'm a
total novice at this - never even seen an actual thermocouple.)
Thanks,
Brian

5) From: raymanowen
"I was wondering if I could effectively use the digital thermometer with
thermocouple wire probe by placing the probe in the space between the
stainless steel bowl and the sieve. "
Yes. You must not mechanically anchor the tc probe very close to its tip,
and preferably not to a cold heat sink.
You could scope out Hobby Lobby for some metal tube big enough to encase the
tc wire probe. Bend the tube to match the contour of the bottom of the sieve
mesh. Don't run it straight in on a radial, but scroll it on a short spiral.
Anchor the tube to the mesh with some fine ss model wire at the ends and in
the middle. Push the tc probe through so it extends 4 - 6in, bend it back
and aim it toward the center of the sieve. Anchor the tc probe wire to the
mesh at both ends of the tube and Very loosely in the middle of the extended
probe wire.
The reason for all that is to fix the measuring point from roast to roast,
and maximize the exposure of the measuring junction to the heat without
fastening it to a cold surface anywhere near it. If you protect the wire
from the heat you're trying to measure, it's snow good.
Cheers -RayO, aka Opa!
"The indisputable truth is that no coffee is fresh if it isn't fresh
roasted." - - Martin Diedrich
25-Mar-07 21:05
On 3/24/07, Brian Kamnetz  wrote:
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-- 
"When the theme hits the bass, I dance the Jig!" - -Virgil Fox at the Mighty
Wichita (ex- NYC Paramount) WurliTzer- 1976

6) From: John Moody
This is a multi-part message in MIME format.
I have put a thermocouple into my HG/DB setup a number of times.  The roast
method has such strong audio/visual/scent indications that the TC is not of
much added value.
That being said, I used a very small clamp to hold the TC to the inside of
the bowl, with the tip into the bean mass.  I usually “stir” with a big
spoon, but find a whisk works better when the TC is in.
John


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