Well, I've ended the "fan under grill" experiment and concluded it's
probably not a great idea.
Roasting today,  I found that with the fan on, temperatures according
to my thermocouple were constantly climbing and fluctuating wildly,
even with all burners at their lowest setting.  Temp reading steadied
at ~650F,  but I kept on roasting anyway, and ended up baking a batch
of Moka Kadir at 14 minute 1st crack, so all that heat wasn't making
it into the beans.  Turned the fan off for the next batch, and things
were a bit more normal (at least what I've come to expect for my rig).
Since the fan is making things less predictable instead of more,  I'm
concluding it's a bad idea..  as to why 650 F gave me such a slow
roast, I can only give the very scientific observation of "something
strange is going on".
I know at least one person mentioned they might try it,  but I'd
caution against it for now unless you want to experiment (and risk
coffee).
--mike

My idea is to put a big furnace blower under the grill, and turn the
flame Off when I turn the blower On. The air blast will rapidly cool
everything, including the metal roasting drum and beans.
Currently, I just have a cardboard mockup of the roasting muffle on
top of the gas grill. I've run the blower without lighting any fire,
obviously. It worked after a fashion, because the mockup literally
split- into pieces, and left the scene.
With the ductwork/ muffle made of 3/8ths concrete board between sheet
metal layers and only a pound or two of beans in the drum, it could
all get fairly buoyant on high blow. It's a 3-speed PSC motor (same as
ceiling fans), so I can "tach" it up or down a lot with the taps and
switching capacitors. It's not about to overheat with the motor in the
middle of the blower.
I don't plan to run the blower at all during the roast- it's strictly
for cooling.down in a hurry.
Cheers, Mabuhay -RayO, aka Opa!
Got Grinder?
On 10/16/07, Mike Koenig  wrote:
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Huh?
This is the first post from RayO that I think I understood!  You have such a
grasp of the english language and use it to its fullest.  My little brain
just can't handle it.  Fun reading, but my head hurts a bit afterwards.
Kinda like reading Brett's "humor".
;-)
Dave
On 10/19/07, raymanowen  wrote:
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