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Topic: Gene cafe temperature (4 msgs / 98 lines)
1) From: Martina Augustinova
This is a multi-part message in MIME format.
The Gene cafe roaster is truly impressive as well as the detailed review
and video. It's definitely very tempting :-)
I was wondering about the temperature readings during the roast - what
is it that's being measured? Is the bean mass temperature or is the air
temperature? I've found a post on alt.coffee saying:
 
<Snip>
instead of bean mass temp as an outcome variable.<<<<<<
 
Happy Easter,
Martina

2) From: raymanowen
IR temperature indication, drum surface temperature, incident air
temperature and exhaust air temperature all are related to "the bean
temperature."
If the temperature is changing, none of the indicators is true, with the IR
being the worst. The cheap IR's have checkered accuracy for two reasons:
1)- The IR radiation depends on the temperature and emissivity of the body-
if the temperature rises while the beans are turning to ash, the IR detecto=
r
could read nearly constant.
2)- The IR is reading a point on the surface, which could be a local hot
spot or cool spot.
No matter how the temperature reading is derived, it's related to the degre=
e
of roast and the end flavor in the cup.
All you want is the best possible flavor in the cup from the beans you have
to roast. You could go nuts with a Leeds & Northrup chart recorder and
several T/C, RTD and IR inputs on different colored curves. In the end each
curve would have some relationship to cup flavor.
Cheers -RayO, aka Opa!
"May the roast be fast; may the roast be safe..." - - Tony Hullman, pres.
Indianapolis Motor Speedway 1957 -Aw, he said race, not roast~

3) From: Peter Zulkowski
Ray,
Do you have any ideas about how to duplicate the controls and readouts 
on the Gene Cafe?
Thanks,
PeterZ
raymanowen wrote:
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4) From: raymanowen
I oversimplify. I'm not any good at duplicating, but the Love controllers
I've seen were self-contained in 1/4 and 1/8 DIN housings. Some OEM's use
Love control boards with remote setpoint pots and readouts. Love and Omega
Engineering's controls were at least similar, and certainly aren't the only
ones.
The Gene Cafe's cooling is the sticky wicket. With any stronger air flow,
the beans would be blown to the end of the tube and would not agitate. The
additional blower capacity would cost big bucks and only be used at the tai=
l
end of the roast.
That cost is impossible to justify when the existing controls can
compensate.
The Tesla Roaster and Grand Slam cooler are different. The latter uses the
S/S screen mesh colander in the video. I snagged a unit furnace blower out
of a pristine gas furnace headed for a metal dumpster in a metal recycling
yard. Lying on its side with the motor in the bottom venturi, I just set th=
e
colander in the open 9" venturi inlet of the blower.
With a 3-speed motor, I just wired it for high blow. The largest batch I
slammed was 800g of smoking Ethiopian Sidamo a few snaps into 2nd crack.
Stopped in 5 s, cool in 10 and dead cold in 30 seconds.
I should have gotten two- it would have cost me $4.00 total ! ! I should
have gotten one whole furnace for $35. It was pristine and clean. Mine is
the original- 1957.
A mind is a terrible thing...        Especially mine, drat.
Cheers -RayO, aka Opa!
Got Grinder?
On 4/17/06, Peter Zulkowski  wrote:
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-
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--
"When the theme hits the bass, I dance the Jig!" - -Virgil Fox at the
Wichita WurliTzer


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