HomeRoast Digest


Topic: What we as homeroasters could really use! (14 msgs / 311 lines)
1) From: james McDougal
Hello everybody,
I keep thinking about a product that we used in the laboratory which could
be modified to provide bean temperatures fairly easily.
There was (is) a temperature measuring device called the "mini-mitter". It
was a hard cylindrical plastic device about the size of the fingernail digit
of your little finger. This device, containing a small battery, was
surgically implanted into the peritoneal cavity of a rat and transmitted
body temperature over an AM frequency, where the distance between the
distance between square wave pulses was indirectly proportional to the
temperature environment of the transmitter. An AM receiver converted the
pulses into temperatures and plotted them. We used to investigate the
effects of drugs on body temperature.
Wouldn't it be perfect if we had something like this to dump in with the
beans to be roasted!  Obviously the sensitivity (temperature range) and
ability to withstand the high heat of a roaster would have to be improved
and it would be good if it could made much smaller. I believe that the
manufacture used to be done in a "mom & pop" shop in the late 70's but
appears to have been purchased by a larger company in Bend Oregon -http://www.minimitter.com/animal_products.cfmI didn't see a product that looks like the one we used, but this company
probably would have the ability to make a product that would accurately
measure bean temperatures, at least in non air roasters. Hard to know what
it would end up costing or whether there would be enough of a market to make
it worth their while.
Just dreamin'
Mac
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

2) From: Allon Stern
On Jan 8, 2009, at 2:53 PM, james McDougal wrote:
<Snip>
You'd need to figure out some way to account for the doppler shift as  
the thing tumbled around in the drum :)
Okay, you could have your receiver mounted along the axis of  
rotation....still, it's a cute idea :)
-
allon
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

3) From: Seth Grandeau
The "Running Wheel" on their website looks a little like a Behmor drum.  You
might be on to something. :)
On 1/8/09, james McDougal  wrote:
<Snip>
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

4) From: james McDougal
Hey, perhaps the "temperature bean" could be incorporated into a roaster -
all you would have to do is set the profile and the bean temperature for the
coffee beans to dump ;-) Might just make roasting easy enough for everybody!
;-)
Mac
On Thu, Jan 8, 2009 at 3:35 PM, Seth Grandeau  wrote:
<Snip>
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

5) From: Oolan Zimmer
Not to rain on your parade, but does anyone know of any batteries that
will operate at sustained temperatures of 500F?  The only technologies I
know of are liquid sodium and related.  And designing a liquid sodium or
sodium sulfur battery that's small and can be rolled around gets into
exotic R&D territory.
Of course, you could generate the power using a Seebeck Effect
generator, presuming the interior of the device is cooler than the
exterior.  But again I think we're venturing into exotic territory. 
Oolan Zimmer
ozimmer
Seth Grandeau wrote:
<Snip>
-- 
Oolan Zimmer
ozimmer
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

6) From: R Nepsund
The device from the first email is powered by a near by radio transmitter so
that they don't have batteries.
On Thu, Jan 8, 2009 at 1:03 PM, Oolan Zimmer  wrote:
<Snip>
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

7) From: Seth Grandeau
Wouldn't it be easier to just use a "bean mass" temp by having a
thermocouple that would sit in and around the beans?  As long as your
roasting method offered good movement/mixing and you're not blasting the
beans with very high heat, shouldn't that be good enough?
I use the Behmor, so that's what I'm picturing.  You would need to have the
thermocouple integrated into the drum itself, then the system could have a
programable shutoff (for your desired roast level), with the maximum bean
mass temp set low enough that you can't go past vienna (so no fires).  I
would be willing to pay a $100 premium for that functionality over what I
currently have with the Behmor 1600.
On 1/8/09, Oolan Zimmer  wrote:
<Snip>
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

8) From: Tom & Maria - Sweet Maria's Coffee
I think the device could be larger than the coffee bean as long as it 
had similar thermal dynamics. It would be great because if it truly 
had the same density and material properties of a coffee bean then it 
would work well independent of the roaster type or size. I know this 
was brought up before in a discussion, and at some point I bet we 
will see something like this. Heck - I jiust bought one of those 
wireless SD cards today that also has geo-tagging --- who would have 
thunk we would have that 5 years ago. Which reminds me, all this 
technology makes me feel old! I just had to buy a 4mm tape drive off 
ebay to recover some old archived files. I thought tape drives would 
be around forever, which is why I backed up to them!!!
Tom
--
                   "Great coffee comes from tiny roasters"
            Sweet Maria's Home Coffee Roasting  -  Tom & Maria
                      http://www.sweetmarias.com                Thompson Owen george_at_sweetmarias.com
     Sweet Maria's Coffee - 1115 21st Street, Oakland, CA 94607 - USA
             phone/fax: 888 876 5917 - tom_at_sweetmarias.com
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

9) From: Oolan Zimmer
This got me looking at the concept more closely.  Here's the closest
thing I could find to our application:http://news.uns.purdue.edu/x/2007b/071030SadeghiMems.htmlWireless temperature monitoring, remotely powered, up to 570F operating
temperature.  If the military can get it, then it can be done.  Since a
university is developing it, the technology isn't classified.  If it can
be done, eventually the likes of us can get our hands on it, though
possibly at an insane price.
Conference paper abstract:http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?tp=&arnumberC88559&isnumberC88308Oolan Zimmer
ozimmer
R Nepsund wrote:
<Snip>
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

10) From: Luis Zaman
Wow, I haven't even heard of these fancy new SD cards. I'm pretty impressed.
You're making me feel out of the tech loop, and I'm working on a PhD in
Computer Science!!
Luis
On Thu, Jan 8, 2009 at 8:22 PM, Tom & Maria - Sweet Maria's Coffee <
sweetmariascoffee> wrote:
<Snip>
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

11) From: Dave
I bought one of the first ones for my wife for Christmas last year. They had
only been on the market a couple weeks. She wanted a small camera, so I
chose one that used SD to be compatible. Its very cool. Bought one of the
newest with the geo-tagging this year. She's going to use it with an adapter
in the Nikon SLR.http://www.eye.fi/Dave
Some days...
It's just not worth chewing through the leather straps
On Thu, Jan 8, 2009 at 11:12 PM, Luis Zaman  wrote:
<Snip>
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

12) From: raymanowen
Non-toxic ways to get power in to the heated zone and signal out.
For power in, it would be pretty elementary to set up a slip ring on the
drum shaft. It's ancient, but trouble free technology. Automotive
alternators have used slip rings on the armature for years.
Another Nikola Tesla method would be to set up a "Magnetic Slip Ring," with
a flat washer shaped primary (ac) coil, stationary and concentric to the
drum's shaft.
The secondary coil would be similar, with fewer turns for a step down ratio
to supply a silicon rectifier and mil-spec a/d components.
I think you could find components (Maybe Not at Radio Shack) that operate
fine at roasting temperatures. Temperature telemetry is not that tough. If
the chips need dc, just use HF or low RF to couple the power. Small ceramic
capacitors would be temperature immune, and provide all the filtering you
need.
There are books on this stuff, and we did it all the time at CSMines
Research Institute, and Caterpillar's Research Proving Grounds many years
earlier.
There has to be a simpler way than trying to measure the temperature inside
a turning drum- any related, stable temperature would be fine. You could
even measure the infra red from the drum reflected off the Moon.
Cheers -RayO, aka Opa!
Coffee goes through Hell to get roasted. Don't make it repeat, with a Gritty
Shinder...
On Thu, Jan 8, 2009 at 2:03 PM, Oolan Zimmer  wrote:
<Snip>
-- 
"When the theme hits the bass, I dance the Jig!" - -Virgil Fox at the Mighty
Wichita (ex- NYC Paramount) WurliTzer- 1976
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

13) From: Ira
At 05:41 PM 1/9/2009, you wrote:
<Snip>
You could also place a bi-metalic thing inside the drum and measure 
the distance it moves in relation to something else. Then all the 
sensing stuff is outside the drum.
Ira
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

14) From: Oolan Zimmer
Ira wrote:
<Snip>
Or you could design a drum with an open end and use a standard
thermocouple.  Or you could design a rotating joint into the drum that
carried a wired thermocouple's signal.
I think a "measuring bean" could help those who are designing roasters
to understand how an individual bean's temperature varies as it moves
around the drum while surrounded by other beans.  For production use,
it's overkill.
-- 
Oolan Zimmer
ozimmer
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20


HomeRoast Digest