HomeRoast Digest


Topic: Simple iRoast2 Thermocouple Placement (9 msgs / 248 lines)
1) From: Steve Hay
All,
I've tried TCing my iRoast2 in a few ways and I believe I have found the
"best" way to do it.  I'm curious if anyone else has tried any other ideas =
I
haven't with better success.  There is a metal part that comes out of the
glass/plastic sleeve which is separated by a rubber gasket.  The TC can be
placed in the sleeve by being threaded down between the plastic and glass
and then back up the glass by where the rubber gasket would make a seal.
Once inside, it can make a sharp inward turn and get a good bed temperature
without touching any metal parts.
Other ways I've tried:
1) Under the roast chamber and through one of the airflow holes and into th=
e
chamber:  I think doing this was heating up the measurement wire in such a
way to make the temperature more a function of the heated air temperature
than that of the roastbed..  This is because quite a bit of the wire is
being blown on by this hot air, and I think the wire heats and affects the
measurement.  Also, doing it this way its possible for the TC to touch meta=
l
when the beans are added and moved through the chamber during roasting.
Finally, its difficult to ensure the TC is in the exact same place each tim=
e
a measurement is taken, since its just hanging in there.
2) Through the chaff collector and down into the chamber:  This way also
gave me rather inconsistent measurements depending on where the probe ended
up.  I found that closer to the edge I got lower temperatures by quite a bi=
t
as compared to if the probe was nearer the center.  Also doing this made th=
e
TC right in the way when emptying the chaff collector.  Also the wire was
being pinched by the chaff collector part which was pushed down by the lid,
which I didn't like too much.  Sometimes the TC would end up resting on a
metal part (hotter) and I wouldn't see it until the roast started.
3) Outlet temperature:  This one did ok with consistency but I felt I wante=
d
to measure closer to the bean.  Such a measurement doesn't seem to take int=
o
account the circulation speed of the beans.
Why the final way is better:
The measurements are consistent because I never have to move the TC when I
am empying the chaff collector.  Only a small 1/2" sticks out of the wall i=
n
such a way that it cannot touch any metal parts, except perhaps the bottom,
which I am not too worried about actually happening.  The TC is in the
bean-bed any parts of the wire also also in the bean bed before exiting the
chamber.  No undue cycling of the TC wire or pinching happens because I
route it in a place where there is some clearance (where the hooks twist to
engage the base.  Finally, no drilling or permanent mod to the iRoast is
necessary, although some chaff gathers around where the TC comes out.  I've
thought about cutting a small slit in the gasket for the TC wire.  Right
now, I am too much in love with the idea that I don't have to do anything
irreversible to my unit to measure these temps though.
Warm regards,
Steve
--
Steven Hay
hay.steve -AT- gmail.com

2) From: Aaron Peterson
I ordered a TC that should arrive this coming week that I plan to use
with my iRoast 2.  I obviously haven't tried it yet, but I'll report
my experiences/success/failure when I do :-)
You don't happen to have any pictures of the setup you've had the best
success with do you?
Aaron
On 3/5/06, Steve Hay  wrote:
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3) From: Woody DeCasere
do you have any pic's?
On 3/5/06, Aaron Peterson  wrote:
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--
"Good night, and Good Coffee"

4) From: Larry English
Steve,
 I bugged Aaron for pix of his iRoast-TC mod - oops!  It was your mod.  I
can't quite figure out how you snaked the TC into the bean mass of your
iRoast - perhaps a photo or different words would help.  I'm a math teacher
but am visualization-challeged - not a good combo!  Ah, well...
Larry
On 3/5/06, Steve Hay  wrote:
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5) From: Sandy Schaefer
This is a multi-part message in MIME format.
  I placed the probe sticking up half an inch into beans by drilling a =
couple holes. The probe is a third of way from glass toward center on =
bottom of metal roasting chamber. Drill from the top down into metal =
there will be a second metal sheet to go though. Then drill at an angle =
though plastic
housing toward outside. This hole is at very bottom rim of roasting =
chamber where it locks onto bottom component. Note the inside of this =
rim there are place where plastic is thicker for locking into bottom. =
Then snake the probe though the holes. Mind was a good fit with the =
probes insulation with no movement of probe at all. The temperature =
readings are consistent. To be honest I was afraid to do this operation =
but it turned out very well. 
Mark   

6) From: Steve Hay
On 3/6/06, Larry English  wrote:
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Everyone,
I don't presently have a digital camera that I can charge and take pictures
with.  However, when I get a chance this weekend I will bring out the Gimp
(Gnome Image Manipulation Program) and try to draw a picture.
But if you are in a hurry, just notice the four symmetric screws at the
bottom of the roast chamber.  Take those out and you can see the three
pieces I am talking about.  The annulus, the glass chamber, and the gasket
between them.. The TC snakes around the glass chamber and goes between it
and the gasket to poke its head out just a bit into the hot place, never
touching any metal.
Steve
--
Steven Hay
hay.steve -AT- gmail.com

7) From: Aaron Peterson
On 3/6/06, Steve Hay  wrote:
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Sweet.  I'm in no hurry...  The Gimp rules by the way :-)  I happen to
prefer it to Photoshop given the choice...  I'm a huge Pulp Fiction
fan too, definitely in my top 10 favorite movies, and on the long list
of movies I've seen WAY TOO MANY times.  Along with The Big Lebowski,
High Fidelity, and on and on...
Thanks for your time,
Aaron

8) From: ALW
Steve Hay  wrote on Sun Mar 5 09:15:01 2006
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A brief update on this old thread.
I found Steve's posting, seeking a better way after stripping
the insulation of my TC in pushing it down through the chaff
collector.
I implemented something close to Steve's idea, and posted some
pics here:
  http://coffeesnobs.com.au/YaBB.pl?num75866065/0#4 
Hope someone finds it useful!

9) From: Ross
Or even simpler, get the 8in dial thermometer and put it in by drilling a 
hole in the top screen and chaff collector. I just put a piece of thin 
cardboard below the dial to deflect hot air and insert to just off the 
bottom.  Works perfect.
Ross


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