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Date: 07 Jan 2007 21:35:24
From: Mike Hartigan
Subject: Can't hear cracks - visual clues?
In my iRoast 2, sometimes I can hear the cracks as plain as day,
sometimes I can't hear a thing. Since it's a rare batch that doesn't
taste really, really good, I'm assuming that my roasts are
progressing normally, crack(s) and all. I was wondering - are there
visual clues that indicate that the cracks have or are occurring?
For example, if I see chaff flying, is it safe to assume that I've
reached the first crack? What about when the beans double in size?
Are there any visual manifestations that traditionally accompany
second crack?

--
-Mike




 
Date: 09 Jan 2007 04:56:22
From: ronnie.b
Subject: Re: Can't hear cracks - visual clues?


On Jan 7, 11:47 pm, "Ken Fox"
<morceaudemerdeThisMerdeG...@hotmail.com > wrote:
>
> Unfortunately, I think this recommendation may be less useful for air
> roasters than it is for drum roasters and most people reading this will have
> air roasters. Oh well. And it won't be of any use to the dog dish/heat gun
> people. Sorry.
>
> ken

Not true. I have a P1 and use the RT-912 from
http://www.indoorhealthproducts.com/912.htm. I drilled a hole into the
side of the popper through the roast chamber just above the aluminium
and it's suspended about an inch above the bottom. I get consistent
readings and consistent beans every time.

Ron



  
Date: 09 Jan 2007 08:09:17
From: Ken Fox
Subject: Re: Can't hear cracks - visual clues?
"ronnie.b" <ronbalut@verizon.net > wrote in message
news:1168347382.796077.195720@s80g2000cwa.googlegroups.com...
>
>
> On Jan 7, 11:47 pm, "Ken Fox"
> <morceaudemerdeThisMerdeG...@hotmail.com> wrote:
>>
>> Unfortunately, I think this recommendation may be less useful for air
>> roasters than it is for drum roasters and most people reading this will
>> have
>> air roasters. Oh well. And it won't be of any use to the dog dish/heat
>> gun
>> people. Sorry.
>>
>> ken
>
> Not true. I have a P1 and use the RT-912 from
> http://www.indoorhealthproducts.com/912.htm. I drilled a hole into the
> side of the popper through the roast chamber just above the aluminium
> and it's suspended about an inch above the bottom. I get consistent
> readings and consistent beans every time.
>
> Ron
>

"less useful" does not equate to "useless." The problem with using digital
thermometry with small air roasters is consistent probe placement and the
fact that the air temperature can change drastically and fast without the
bean temps changing in the same way. In contrast, with conductive heating
through a drum, it is hard for the beans to be too far out of sync with what
a probe in a fixed position will show.




   
Date: 09 Jan 2007 22:56:00
From: I->Ian
Subject: Re: Can't hear cracks - visual clues?
On Tue, 9 Jan 2007 08:09:17 -0700, "Ken Fox"
<morceaudemerdeThisMerdeGoes@hotmail.com > wrote:

> The problem with using digital
>thermometry with small air roasters is consistent probe placement and the
>fact that the air temperature can change drastically and fast without the
>bean temps changing in the same way.

It's definitely possible, but not simple.

With my FR I have a fixed TC in the chaff collector and control the
element voltage with a fixed air control. Roast times, _AND PROFILE_
are completely controllable up to about 15 minutes

Crack temps are within a couple of degrees of the bean temp probe in
the HotTop, with first starting in the 390 to 395 range and second in
the 435ish range. Both these numbers agree closely with industry
standard numbers.

As with all things coffee, achieving excellent results requires care
and attention.


 
Date: 09 Jan 2007 03:40:57
From: JulesG
Subject: Re: Can't hear cracks - visual clues?
I- >Ian wrote:
>
> As the point of this forum is the exchange of information, that
> information should be readily communicable.
>
> If first crack occurs at 425=B0F in your setup, that may allow you to
> repeat roasts, but may prove to be an impediment to sharing
> information with another whose first crack occurs closer to accepted
> values in another model of roaster.
>
> That was the point of my suggestion to move the probe to get numbers
> more in line with standard values.
>
> Since your probe is not fixed, why not try a timed roast with known
> parameters and see if the numbers are more in line with standard
> values.

Ian

Knowing the first crack temperature is not very important in my opinion
since one will rarely stop the roast when that temperature is reached.
Also, to measure that temperature, one would have to know exactly when
first crack starts by hearing it, a difficult proposition with the iR2.
What's important is to know at what temperature to stop the roast.

I think that info about my roasts could be shared with others. My
probe is always installed the same way at the same place. I suspect
that other users would get the same results with their iR2 if they
install a TC at the same location using the same profile and stopping
the roast at the same temp.

Unfortunately, this implies installing a TC probe, since the temp
readings of the iR2 are quite meaningless. My modification is quite
simple, can be installed in a few minutes and a digital thermometer
with TC costs 20$. I feel it has made my iR2 a much better roaster.

I can also repeat roasts using roasting time but this would be more
difficult to share since voltage must be controlled. This is more
complicated and a variac is quite expensive.

Don't get me wrong, I am not recommending that others make and use this
modification, I just want to share with others how I do it since it
works well for me. I don't think that it is very useful for others to
know that I roast Mokha at 460 F. using a given profile since our
tastes may vary and that I may not have found the optimum recipe.
However, it is quite useful to be able to repeat the very same roast
time after time once one has found a recipe that he or she likes by
experimenting with different roasting times. However, sharing profiles
and temperatures would provide a good starting point for
experimentation.



  
Date: 09 Jan 2007 22:42:38
From: I->Ian
Subject: Re: Can't hear cracks - visual clues?
On 9 Jan 2007 03:40:57 -0800, "JulesG" <jules.gobeil@videotron.ca >
wrote:

> What's important is to know at what temperature to stop the roast.

Sadly, this is all too common a misconception with many roasters.

It is not just the end point, but how you arrive at the end point that
dramatically changes the flavors.

If roasters sees to maximize the potential of a bean, they needs to
control how they arrive at the end temperature. If they fail to do
that, they will have fresh coffee. Great coffee, purely chance.


 
Date: 08 Jan 2007 17:28:17
From: Flasherly
Subject: Re: Can't hear cracks - visual clues?

Mike Hartigan wrote:
> cracks. The ambient light and the cleanliness of the glass tend to
> be variable. Combined with the fact that I've been diagnosed with
> terminal, inoperative color blindness, I don't want to rely on the
> bean color. I was hoping to uncover a visual indicator that the
> cracks are occurring.

In painting, colors may be coordinated for a grayscale, decreasing in
hue, saturation, and overall vividness as a mechanism for point
perspective. The closer to an subject the more intense the colors,
while as its perspective fades to a horizon line of a more distant
perspective, colors are portrayed less, for muted contast within gray.
In fact, the gray gradiant scale is used for a prop device, a strip of
paper with white on one end and black the other set aside and tacked to
an easel. In between is a standard measure of infinite grays fading
between light and dark. With white and black admixed to a single
source of pigmented color medium, fluid contrasts are readily obtained
and variously mixed by binders. Not so with pastels. I once visited
with a pastel artist who showed me techniques of the medium. Each
gradiant of the color is set, manufactured, and individually purchased.
Ten gradiants to a colour as I recall standards. Browns of darker and
lighter hue may also matched by greys, although not without a base
window to clearly see through to them, and a constant light as a
reference of angstroms (how color temperature is measured) to judge
them. When using fluorescent and incandescent sources combined, for
instance, the color is said to more closely approximate refraction
characteristics of sunlight. Constant light, as a measure of gray,
more importantly then need be of the same base intensity, how brightly
a light burns adjacent to a development of "gray within browns" of your
burning coffee.



 
Date: 08 Jan 2007 16:47:30
From: JulesG
Subject: Re: Can't hear cracks - visual clues?
I use a iR2 and I can get repeatable results by controlling the roast
either by time or temperature. I also find it difficult and unreliable
to hear the cracks - sometimes it is easy, sometimes it is impossible.

Given a stable environment (outside temp, voltage, profile, quantity,
bean) I get similar results time after time by stopping the roast after
a given roasting time or at a given temperature measured with a
thermocouple.

I install the thermocouple as shown on this picture, after threading it
through slightly enlarged holes in the lid and the chaff collector.

http://julesgobeil.com/private/ir2-tc-kw.jpg

It is trial and error first to find the correct settings to my liking
for a given bean. Once they are known it is very simple to get the
same results time after time.

Jules



  
Date: 08 Jan 2007 19:10:08
From: I->Ian
Subject: Re: Can't hear cracks - visual clues?
On 8 Jan 2007 16:47:30 -0800, "JulesG" <jules.gobeil@videotron.ca >
wrote:

>I use a iR2 and I can get repeatable results by controlling the roast
>either by time or temperature. I also find it difficult and unreliable
>to hear the cracks - sometimes it is easy, sometimes it is impossible.
>

Hence, iRoar.

>Given a stable environment (outside temp, voltage, profile, quantity,
>bean) I get similar results time after time by stopping the roast after
>a given roasting time or at a given temperature measured with a
>thermocouple.
>
>I install the thermocouple as shown on this picture, after threading it
>through slightly enlarged holes in the lid and the chaff collector.
>
>http://julesgobeil.com/private/ir2-tc-kw.jpg
>
>It is trial and error first to find the correct settings to my liking
>for a given bean. Once they are known it is very simple to get the
>same results time after time.
>
>Jules

It would be possible to mount a sensing device, say an optical device
that measured bean accelleration and judge roasts by those numbers.
However the data would be difficult to communicate to another roaster
[person] using a different machine.

As the point of this forum is the exchange of information, that
information should be readily communicable.

If first crack occurs at 425F in your setup, that may allow you to
repeat roasts, but may prove to be an impediment to sharing
information with another whose first crack occurs closer to accepted
values in another model of roaster.

That was the point of my suggestion to move the probe to get numbers
more in line with standard values.

Since your probe is not fixed, why not try a timed roast with known
parameters and see if the numbers are more in line with standard
values.


 
Date: 08 Jan 2007 12:12:31
From:
Subject: Re: Can't hear cracks - visual clues?

Mike Hartigan wrote:

> Are there any visual manifestations that traditionally accompany
> second crack?
>
> --
> -Mike

I've been roasting to between 1st and 2nd crack; looking at the level
of darkness in the bean. As I haven't been changing bean variety, I've
learned the level of darkness that I like; perhaps that would work for
you - Mike



  
Date: 08 Jan 2007 18:30:53
From: Mike Hartigan
Subject: Re: Can't hear cracks - visual clues?
In article <1168287151.449251.110670@51g2000cwl.googlegroups.com >,
mhorowit@cox.net says...
>
> Mike Hartigan wrote:
>
> > Are there any visual manifestations that traditionally accompany
> > second crack?
> >
> > --
> > -Mike
>
> I've been roasting to between 1st and 2nd crack; looking at the level
> of darkness in the bean. As I haven't been changing bean variety, I've
> learned the level of darkness that I like; perhaps that would work for
> you - Mike

Don't misunderstand - the coffee I'm getting is pretty damn good. I
really have no complaints. I watch the roast progress, keeping an
eye on the displayed temp. I have a good TC and a Fluke, but I don't
use it because the displayed temp from the iRoast has, so far, served
as a good enough guide - I'm getting a high level of repeatability.
My concern stems from the fact that I can't reliably correlate my
experience with those of others because I often can't hear the
cracks. The ambient light and the cleanliness of the glass tend to
be variable. Combined with the fact that I've been diagnosed with
terminal, inoperative color blindness, I don't want to rely on the
bean color. I was hoping to uncover a visual indicator that the
cracks are occurring. Reading through the responses, however, I now
see that the cracks are not the 'Holy Grail' of roasting that I
thought they were. If simple temperature monitoring is a 'better'
approach, and temperature monitoring is, indeed, working well for me,
perhaps I'll simply keep doing it this way and not worry about the
cracks.

--
-Mike


   
Date: 12 Jan 2007 22:04:46
From: Johnny
Subject: Re: Can't hear cracks - visual clues?

"Mike Hartigan" <mike@hartigan.dot.com > wrote in message
news:MPG.200c9e3741c8d8fa9898f3@newsgroups.comcast.net...
> In article <1168287151.449251.110670@51g2000cwl.googlegroups.com>,
<snip/ >
> I was hoping to uncover a visual indicator that the
> cracks are occurring.

This is the best visual indicator I've seen but I don't think it will help
much
http://www.sweetias.com/roasting-VisualGuideV2.html




    
Date: 13 Jan 2007 07:36:15
From: Mike Hartigan
Subject: Re: Can't hear cracks - visual clues?
In article <ZD_ph.85484$lD5.65475@newsfe14.phx >,
removethis.huuanito@hotmail.com says...
>
> "Mike Hartigan" <mike@hartigan.dot.com> wrote in message
> news:MPG.200c9e3741c8d8fa9898f3@newsgroups.comcast.net...
> > In article <1168287151.449251.110670@51g2000cwl.googlegroups.com>,
> <snip/>
> > I was hoping to uncover a visual indicator that the
> > cracks are occurring.
>
> This is the best visual indicator I've seen but I don't think it will help
> much
> http://www.sweetias.com/roasting-VisualGuideV2.html

I've not read that in a few years. George Steinert's comments WRT
the iRoast are very interesting. Thank you for that.

--
-Mike


 
Date: 08 Jan 2007 10:24:49
From: Flasherly
Subject: Re: Can't hear cracks - visual clues?

chardinej wrote:
> We have a noisy Rosto roaster but we consistently hear first crack
> above the fan noise. However, don't expect every bean to make a sound.
> We hear about 5-10 cracks usually at about 4-6 minutes after the start
> of the roast (from a cold machine). We've never heard second crack,
> which apparently is softer, but more frequent (more like rice crispys
> in milk- can't remember where I read this). We have been roasting about
> 5-6 minutes past first crack for a medium-dark roast with small spots
> of oil. Oil does not show up right after cooling, only later, so we
> don't use this as a guide. We use smell (slight smell of burning but no
> smoke) and colour of bean to stop the roast. Product seems very good.

Yes - I've seen that, too. The oils and sugars temporarily, though I
probably roaster lighter. I don't get much smell -- or way too much in
the house. I roast under a kitchen range exhaust hood. No smoke and
working almost all off color. Light city roast usually, sometimes
darker but not much. I've never seen that much oil after cooling, just
feel it, though they still look dry. Thanks.



 
Date: 08 Jan 2007 09:37:22
From: chardinej
Subject: Re: Can't hear cracks - visual clues?
We have a noisy Rosto roaster but we consistently hear first crack
above the fan noise. However, don't expect every bean to make a sound.
We hear about 5-10 cracks usually at about 4-6 minutes after the start
of the roast (from a cold machine). We've never heard second crack,
which apparently is softer, but more frequent (more like rice crispys
in milk- can't remember where I read this). We have been roasting about
5-6 minutes past first crack for a medium-dark roast with small spots
of oil. Oil does not show up right after cooling, only later, so we
don't use this as a guide. We use smell (slight smell of burning but no
smoke) and colour of bean to stop the roast. Product seems very good.

John


Flasherly wrote:
> Mike Hartigan wrote:
> > In my iRoast 2, sometimes I can hear the cracks as plain as day,
> > sometimes I can't hear a thing. Since it's a rare batch that doesn't
> > taste really, really good, I'm assuming that my roasts are
> > progressing normally, crack(s) and all. I was wondering - are there
> > visual clues that indicate that the cracks have or are occurring?
> > For example, if I see chaff flying, is it safe to assume that I've
> > reached the first crack? What about when the beans double in size?
> > Are there any visual manifestations that traditionally accompany
> > second crack?
>
> I've a FreshRoast without much in the way of displays. A heatgun, but
> with the minimum added construct for constant control of temperature.
> Variables are fan speed and, indirectly, temperature at an amount of
> beans. Everything left is direct observation. The first crack is most
> pronounced. That's with a fair amount of fan noise at the unit,
> including another rangehood fan. All but unmistakable. I'm not
> concerned with listening for the second crack, smell, watching chaff or
> bean size. Unlike the kaleidoscopic brown in whirling colors under a
> bright LED bulb in anything but direct sunlight. The first crack is
> light and the second looks like a city roast. Degrees are amply
> illustrated, and comparison available by purchasing roasted beans. In
> distinguishing characteristics of a particular bean, I find myself
> limited to a region beyond a light, potentially acidic response, to
> less than a "complex" nature for full city roasts. More interesting and
> apt considered complex, perhaps within some provision for detracting
> what origins may suggest from a common, albeit added, preference for
> smoke to qualify the darker penchant. Smoke, though, which for now,
> I'll think of as tobasco on an otherwise perfectly good steak.



 
Date: 08 Jan 2007 09:18:00
From: Flasherly
Subject: Re: Can't hear cracks - visual clues?

Mike Hartigan wrote:
> In my iRoast 2, sometimes I can hear the cracks as plain as day,
> sometimes I can't hear a thing. Since it's a rare batch that doesn't
> taste really, really good, I'm assuming that my roasts are
> progressing normally, crack(s) and all. I was wondering - are there
> visual clues that indicate that the cracks have or are occurring?
> For example, if I see chaff flying, is it safe to assume that I've
> reached the first crack? What about when the beans double in size?
> Are there any visual manifestations that traditionally accompany
> second crack?

I've a FreshRoast without much in the way of displays. A heatgun, but
with the minimum added construct for constant control of temperature.
Variables are fan speed and, indirectly, temperature at an amount of
beans. Everything left is direct observation. The first crack is most
pronounced. That's with a fair amount of fan noise at the unit,
including another rangehood fan. All but unmistakable. I'm not
concerned with listening for the second crack, smell, watching chaff or
bean size. Unlike the kaleidoscopic brown in whirling colors under a
bright LED bulb in anything but direct sunlight. The first crack is
light and the second looks like a city roast. Degrees are amply
illustrated, and comparison available by purchasing roasted beans. In
distinguishing characteristics of a particular bean, I find myself
limited to a region beyond a light, potentially acidic response, to
less than a "complex" nature for full city roasts. More interesting and
apt considered complex, perhaps within some provision for detracting
what origins may suggest from a common, albeit added, preference for
smoke to qualify the darker penchant. Smoke, though, which for now,
I'll think of as tobasco on an otherwise perfectly good steak.



 
Date: 08 Jan 2007 07:25:40
From: Omniryx@gmail.com
Subject: Re: Can't hear cracks - visual clues?

Ken Fox wrote:
> A professional roaster such
> as yourself who presumably roasts sacks of coffee every week is going to
> develop a skillset not unlike the chef who can judge degrees of "doneness"
> without having to make an incision in the filet or measure the temperature
> of a souffle. That having been said, even professional chefs undercook or
> overcook a steak or a piece of fish, if my own observations in restaurants
> are typical. I've even been served souffles that were incompletely cooked
> in a fine restaurant or two; had they put a thermocouple into the middle as
> it cooked, I doubt that would have happened.

Very true, Ken. And professional coffee roasters are no more immune to
these occasional screwups than are chefs.

I once bought some coffee from one of the absolutely top-shelf roasters
in America. When it arrived, it was obviously grossly underroasted. I
sent it back with a note. By next day UPS, I received a replacement
along with an apologetic note acknowledging their mistake. The beans
were correct, the roaster simply had a brain fart. It happens.

That's why your recommendations re thermometry are right on target.



  
Date: 08 Jan 2007 09:49:34
From: Ken Fox
Subject: Re: Can't hear cracks - visual clues?
<Omniryx@gmail.com > wrote in message
news:1168269940.390836.149240@38g2000cwa.googlegroups.com...
>
>>
> That's why your recommendations re thermometry are right on target.
>

Thermometry is so cheap it isn't even something to brag about. A very good
digital thermometer with a K-type probe can be had for less than $20. An
acceptable digital thermometer can be had for little more than $10. And an
oven thermometer has got to be less than even that.




   
Date: 08 Jan 2007 11:50:53
From: Craig Andrews
Subject: Re: Can't hear cracks - visual clues?

"Ken Fox" <morceaudemerdeThisMerdeGoes@hotmail.com > wrote in message
news:50fauvF1f6l4nU1@mid.individual.net...
> <Omniryx@gmail.com> wrote in message
> news:1168269940.390836.149240@38g2000cwa.googlegroups.com...
>>
>>>
>> That's why your recommendations re thermometry are right on target.
>>
>
> Thermometry is so cheap it isn't even something to brag about. A very
> good digital thermometer with a K-type probe can be had for less than
> $20. An acceptable digital thermometer can be had for little more
> than $10. And an oven thermometer has got to be less than even that.
>

& EVERYONE'S seen this one, I'm sure! {;-)
http://webtronics.stores.yahoo.net/digtherwkpro.html
Craig.



    
Date: 19 Jan 2007 02:36:41
From: The Other Funk
Subject: Re: Can't hear cracks - visual clues?
Finding the keyboard operational
Craig Andrews entered:

> "Ken Fox" <morceaudemerdeThisMerdeGoes@hotmail.com> wrote in message
> news:50fauvF1f6l4nU1@mid.individual.net...
>> <Omniryx@gmail.com> wrote in message
>> news:1168269940.390836.149240@38g2000cwa.googlegroups.com...
>>>
>>>>
>>> That's why your recommendations re thermometry are right on target.
>>>
>>
>> Thermometry is so cheap it isn't even something to brag about. A
>> very good digital thermometer with a K-type probe can be had for
>> less than $20. An acceptable digital thermometer can be had for
>> little more than $10. And an oven thermometer has got to be less
>> than even that.
>
> & EVERYONE'S seen this one, I'm sure! {;-)
> http://webtronics.stores.yahoo.net/digtherwkpro.html
> Craig.

Plus or minus 8 F at 400 F? You get what you pay for.

Bob
--
--
Coffee worth staying up for NY Times
www.moondoggiecoffee.com



     
Date: 18 Jan 2007 21:51:21
From: Craig Andrews
Subject: Re: Can't hear cracks - visual clues?

"The Other Funk" <bobbie@moondoggie.com > wrote in message
news:Z8Wrh.3985$E35.653@trnddc02...
> Finding the keyboard operational
> Craig Andrews entered:
>
>> "Ken Fox" <morceaudemerdeThisMerdeGoes@hotmail.com> wrote in message
>> news:50fauvF1f6l4nU1@mid.individual.net...
>>> <Omniryx@gmail.com> wrote in message
>>> news:1168269940.390836.149240@38g2000cwa.googlegroups.com...
>>>>
>>>>>
>>>> That's why your recommendations re thermometry are right on target.
>>>>
>>>
>>> Thermometry is so cheap it isn't even something to brag about. A
>>> very good digital thermometer with a K-type probe can be had for
>>> less than $20. An acceptable digital thermometer can be had for
>>> little more than $10. And an oven thermometer has got to be less
>>> than even that.
>>
>> & EVERYONE'S seen this one, I'm sure! {;-)
>> http://webtronics.stores.yahoo.net/digtherwkpro.html
>> Craig.
>
> Plus or minus 8 F at 400 F? You get what you pay for.
>
> Bob


That's 2.0% over the complete full scale 32~932F At 400F that would
be 43% of full scale, 43% of 2% is .86%. round that off to .9%., that's
STILL less than a 1% error..
Craig.



      
Date: 19 Jan 2007 20:17:06
From: The Other Funk
Subject: Re: Can't hear cracks - visual clues?
Finding the keyboard operational
Craig Andrews entered:

> "The Other Funk" <bobbie@moondoggie.com> wrote in message
> news:Z8Wrh.3985$E35.653@trnddc02...
>> Finding the keyboard operational
>> Craig Andrews entered:
>>
>>> "Ken Fox" <morceaudemerdeThisMerdeGoes@hotmail.com> wrote in message
>>> news:50fauvF1f6l4nU1@mid.individual.net...
>>>> <Omniryx@gmail.com> wrote in message
>>>> news:1168269940.390836.149240@38g2000cwa.googlegroups.com...
>>>>>
>>>>>>
>>>>> That's why your recommendations re thermometry are right on
>>>>> target.
>>>>
>>>> Thermometry is so cheap it isn't even something to brag about. A
>>>> very good digital thermometer with a K-type probe can be had for
>>>> less than $20. An acceptable digital thermometer can be had for
>>>> little more than $10. And an oven thermometer has got to be less
>>>> than even that.
>>>
>>> & EVERYONE'S seen this one, I'm sure! {;-)
>>> http://webtronics.stores.yahoo.net/digtherwkpro.html
>>> Craig.
>>
>> Plus or minus 8 F at 400 F? You get what you pay for.
>>
>> Bob
>
>
> That's 2.0% over the complete full scale 32~932F At 400F that would
> be 43% of full scale, 43% of 2% is .86%. round that off to .9%.,
> that's STILL less than a 1% error..
> Craig.


From the fine manual.
Accuracy = +/-(%of reading + number of digits) at 18C to 28C (for the meter
not the probe)
For the 32 F to 932 F range : accuracy = +/- (0.75% of reading + 4 degrees)
then 400 F accuracy = +/- (3 + 4)
OK 8 was too much but wait there's more!
Thermocouple accuracy = +/- 1.5 F or 0.04%
So if everything adds up in the wrong way, you could be off 8.5 F. Now the
chances of that happening are admittedly slim. Still if you don't bang the
thing around, you should get repeatable readings. i.e your 400 < > then my
400 but your 400 is always 400.
Theonly reason I bring ths up is not to bust anyones chops but I keep seeing
people trying to get temperature accuracies of a dynamic environment that
isn't going to happen without huge $s. After 25 years of fixing, adjusting
and calibrating instruments, it bugs me what mfrs. do to make their crap
look good.
Oh and back on topic, to me good roasting isn't about hitting the cracks at
a certain temp. It's a combination of sight sound taste and smell. Don't
develope tunnel vision on just one thing.
Bob
--
--
Coffee worth staying up for NY Times
www.moondoggiecoffee.com



       
Date: 19 Jan 2007 15:40:06
From: Craig Andrews
Subject: Re: Can't hear cracks - visual clues?

"The Other Funk" <bobbie@moondoggie.com > wrote in message
news:6H9sh.730$8P.433@trndny05...
> Finding the keyboard operational
> Craig Andrews entered:
>
>> "The Other Funk" <bobbie@moondoggie.com> wrote in message
>> news:Z8Wrh.3985$E35.653@trnddc02...
>>> Finding the keyboard operational
>>> Craig Andrews entered:
>>>
>>>> "Ken Fox" <morceaudemerdeThisMerdeGoes@hotmail.com> wrote in
>>>> message
>>>> news:50fauvF1f6l4nU1@mid.individual.net...
>>>>> <Omniryx@gmail.com> wrote in message
>>>>> news:1168269940.390836.149240@38g2000cwa.googlegroups.com...
>>>>>>
>>>>>>>
>>>>>> That's why your recommendations re thermometry are right on
>>>>>> target.
>>>>>
>>>>> Thermometry is so cheap it isn't even something to brag about. A
>>>>> very good digital thermometer with a K-type probe can be had for
>>>>> less than $20. An acceptable digital thermometer can be had for
>>>>> little more than $10. And an oven thermometer has got to be less
>>>>> than even that.
>>>>
>>>> & EVERYONE'S seen this one, I'm sure! {;-)
>>>> http://webtronics.stores.yahoo.net/digtherwkpro.html
>>>> Craig.
>>>
>>> Plus or minus 8 F at 400 F? You get what you pay for.
>>>
>>> Bob
>>
>>
>> That's 2.0% over the complete full scale 32~932F At 400F that
>> would
>> be 43% of full scale, 43% of 2% is .86%. round that off to .9%.,
>> that's STILL less than a 1% error..
>> Craig.
>
>
> From the fine manual.
> Accuracy = +/-(%of reading + number of digits) at 18C to 28C (for the
> meter not the probe)
> For the 32 F to 932 F range : accuracy = +/- (0.75% of reading + 4
> degrees)
> then 400 F accuracy = +/- (3 + 4)
> OK 8 was too much but wait there's more!
> Thermocouple accuracy = +/- 1.5 F or 0.04%
> So if everything adds up in the wrong way, you could be off 8.5 F. Now
> the chances of that happening are admittedly slim. Still if you don't
> bang the thing around, you should get repeatable readings. i.e your
> 400 <> then my 400 but your 400 is always 400.
> Theonly reason I bring ths up is not to bust anyones chops but I keep
> seeing people trying to get temperature accuracies of a dynamic
> environment that isn't going to happen without huge $s. After 25 years
> of fixing, adjusting and calibrating instruments, it bugs me what
> mfrs. do to make their crap look good.
> Oh and back on topic, to me good roasting isn't about hitting the
> cracks at a certain temp. It's a combination of sight sound taste and
> smell. Don't develope tunnel vision on just one thing.
> Bob

You have an actual owners manual? Something this cheap probably a folded
piece of paper, lol!
Craig.



        
Date: 19 Jan 2007 21:59:40
From: The Other Funk
Subject: Re: Can't hear cracks - visual clues?
Finding the keyboard operational
Craig Andrews entered:


> You have an actual owners manual? Something this cheap probably a
> folded piece of paper, lol!
> Craig.


Lord no! There is a PDF verizon online. What is really amazing is that it
doesn't read like a bad translation from Chinese.
If anyone really wants to get into the nitty gitty of temperture measurments
go to www.omega.com. You can even get their free Temperature Handbook 5th
edition which will tell you more then you might ever want to know about
measuring temps. It can also be useful as a door stop, a nut cracker or
evento improve your upper body strength.
Bob
--
--
Coffee worth staying up for NY Times
www.moondoggiecoffee.com



         
Date: 19 Jan 2007 17:05:08
From: Craig Andrews
Subject: Re: Can't hear cracks - visual clues?

"The Other Funk" <bobbie@moondoggie.com > wrote in message
news:gbbsh.26$o31.6@trndny04...
> Finding the keyboard operational
> Craig Andrews entered:
>
>
>> You have an actual owners manual? Something this cheap probably a
>> folded piece of paper, lol!
>> Craig.
>
>
> Lord no! There is a PDF verizon online. What is really amazing is
> that it doesn't read like a bad translation from Chinese.
> If anyone really wants to get into the nitty gitty of temperture
> measurments go to www.omega.com. You can even get their free
> Temperature Handbook 5th edition which will tell you more then you
> might ever want to know about measuring temps. It can also be useful
> as a door stop, a nut cracker or evento improve your upper body
> strength.
> Bob


Link please Bob! {;-)
Cheers!
Craig.



          
Date: 19 Jan 2007 22:59:26
From: The Other Funk
Subject: Re: Can't hear cracks - visual clues?
Finding the keyboard operational
Craig Andrews entered:

> "The Other Funk" <bobbie@moondoggie.com> wrote in message
> news:gbbsh.26$o31.6@trndny04...
>> Finding the keyboard operational
>> Craig Andrews entered:
>>
>>
>>> You have an actual owners manual? Something this cheap probably a
>>> folded piece of paper, lol!
>>> Craig.
>>
>>
>> Lord no! There is a PDF verizon online. What is really amazing is
>> that it doesn't read like a bad translation from Chinese.
>> If anyone really wants to get into the nitty gitty of temperture
>> measurments go to www.omega.com. You can even get their free
>> Temperature Handbook 5th edition which will tell you more then you
>> might ever want to know about measuring temps. It can also be useful
>> as a door stop, a nut cracker or evento improve your upper body
>> strength.
>> Bob
>
>
> Link please Bob! {;-)
> Cheers!
> Craig.

http://www.omega.com/literature/domestic.html for US and Canada
https://www.omega.com/literature/international.html for the rest of the
world who have to pay shipping.
Most, if not all you need to know is available on their site. For example:
http://www.omega.com/techref/colorcodes.html is the basic thermocouple
selection chart. Notice the Standard Limits of Error for types J and K
which are the ypes you will normally see in the inexpensive meters. (+/- the
greater of 2.2C or 0.75%)
You might also want to look at http://www.omega.com/thermocouples.html for
the time constants of various sized probes.
If you are really bored under Technical Links look at Useing Thermocouples
for all the gory details.
Bob
P.S. this is ringing back some very unpleasant memories. i need to go roast
something.

--
--
Coffee worth staying up for NY Times
www.moondoggiecoffee.com



           
Date: 19 Jan 2007 18:13:23
From: Craig Andrews
Subject: Re: Can't hear cracks - visual clues?

"The Other Funk" <bobbie@moondoggie.com > wrote in message
news:i3csh.47$qN1.23@trndny02...
> Finding the keyboard operational
> Craig Andrews entered:
>
>> "The Other Funk" <bobbie@moondoggie.com> wrote in message
>> news:gbbsh.26$o31.6@trndny04...
>>> Finding the keyboard operational
>>> Craig Andrews entered:
>>>
>>>
>>>> You have an actual owners manual? Something this cheap probably a
>>>> folded piece of paper, lol!
>>>> Craig.
>>>
>>>
>>> Lord no! There is a PDF verizon online. What is really amazing is
>>> that it doesn't read like a bad translation from Chinese.
>>> If anyone really wants to get into the nitty gitty of temperture
>>> measurments go to www.omega.com. You can even get their free
>>> Temperature Handbook 5th edition which will tell you more then you
>>> might ever want to know about measuring temps. It can also be useful
>>> as a door stop, a nut cracker or evento improve your upper body
>>> strength.
>>> Bob
>>
>>
>> Link please Bob! {;-)
>> Cheers!
>> Craig.
>
> http://www.omega.com/literature/domestic.html for US and Canada
> https://www.omega.com/literature/international.html for the rest of
> the world who have to pay shipping.
> Most, if not all you need to know is available on their site. For
> example:
> http://www.omega.com/techref/colorcodes.html is the basic thermocouple
> selection chart. Notice the Standard Limits of Error for types J and
> K which are the ypes you will normally see in the inexpensive meters.
> (+/- the greater of 2.2C or 0.75%)
> You might also want to look at http://www.omega.com/thermocouples.html
> for the time constants of various sized probes.
> If you are really bored under Technical Links look at Useing
> Thermocouples for all the gory details.
> Bob
> P.S. this is ringing back some very unpleasant memories. i need to go
> roast something.
>

Thanks.., but not what I meant! I meant the PDF for the cheapo meter...,
that EVERYONE...., including Jim Schulman have linked to & talked about.
I give up, outta here & Fri night!, time for a few dozen Staropramen's,
LOL! {;-D
http://iglo.lundegaard.cz/staropramen_new/centrum/eng/index.html
Over & out! {:-o {:-O {:-D
Craig.



            
Date: 20 Jan 2007 02:11:24
From: The Other Funk
Subject: Re: Can't hear cracks - visual clues?
Finding the keyboard operational
Craig Andrews entered:


>
> Thanks.., but not what I meant! I meant the PDF for the cheapo
> meter..., that EVERYONE...., including Jim Schulman have linked to &
> talked about. I give up, outta here & Fri night!, time for a few
> dozen Staropramen's, LOL! {;-D
> http://iglo.lundegaard.cz/staropramen_new/centrum/eng/index.html
> Over & out! {:-o {:-O {:-D
> Craig.

Dooo!
http://webtronics.stores.yahoo.net/digtherwkpro.html
Just under the photo is a link to the PDF.
What's a Staropramen's?
Bob
--
--
Coffee worth staying up for NY Times
www.moondoggiecoffee.com



    
Date: 08 Jan 2007 11:54:03
From: Craig Andrews
Subject: Re: Can't hear cracks - visual clues?

"Craig Andrews" <alt.coffee@deletethis.rogers.com > wrote in message
news:50fb39F1epr3cU1@mid.individual.net...
>
> "Ken Fox" <morceaudemerdeThisMerdeGoes@hotmail.com> wrote in message
> news:50fauvF1f6l4nU1@mid.individual.net...
>> <Omniryx@gmail.com> wrote in message
>> news:1168269940.390836.149240@38g2000cwa.googlegroups.com...
>>>
>>>>
>>> That's why your recommendations re thermometry are right on target.
>>>
>>
>> Thermometry is so cheap it isn't even something to brag about. A
>> very good digital thermometer with a K-type probe can be had for less
>> than $20. An acceptable digital thermometer can be had for little
>> more than $10. And an oven thermometer has got to be less than even
>> that.
>>
>
> & EVERYONE'S seen this one, I'm sure! {;-)
> http://webtronics.stores.yahoo.net/digtherwkpro.html
> Craig.

Or $8.99! http://techbuys2003.stores.yahoo.net/tm-125.html
Craig.



 
Date: 08 Jan 2007 06:04:47
From: Michael Horowitz
Subject: Re: Can't hear cracks - visual clues?
On Sun, 7 Jan 2007 21:35:24 -0600, Mike Hartigan
<mike@hartigan.dot.com > wrote:

>In my iRoast 2, sometimes I can hear the cracks as plain as day,
>sometimes I can't hear a thing. Since it's a rare batch that doesn't
>taste really, really good, I'm assuming that my roasts are
>progressing normally, crack(s) and all. I was wondering - are there
>visual clues that indicate that the cracks have or are occurring?
>For example, if I see chaff flying, is it safe to assume that I've
>reached the first crack? What about when the beans double in size?
>Are there any visual manifestations that traditionally accompany
>second crack?
>

How about smell? - Mike



  
Date: 08 Jan 2007 13:42:52
From: Coffee Contact
Subject: Re: Can't hear cracks - visual clues?

"Michael Horowitz" <mhorowit@cox.net > wrote in message
news:v994q2ps8n6tfkc80cjak8kgvrfs7j58km@4ax.com...
> On Sun, 7 Jan 2007 21:35:24 -0600, Mike Hartigan
> <mike@hartigan.dot.com> wrote:
>
>>In my iRoast 2, sometimes I can hear the cracks as plain as day,
>>sometimes I can't hear a thing. Since it's a rare batch that doesn't
>>taste really, really good, I'm assuming that my roasts are
>>progressing normally, crack(s) and all. I was wondering - are there
>>visual clues that indicate that the cracks have or are occurring?
>>For example, if I see chaff flying, is it safe to assume that I've
>>reached the first crack? What about when the beans double in size?
>>Are there any visual manifestations that traditionally accompany
>>second crack?
>>
>
> How about smell? - Mike


Have to agree with that, smell and taste being closely linked.
Seems to me that
this group places too much emphasis on technology and not enough on taste.

Terry M




   
Date: 08 Jan 2007 07:29:11
From: Ken Fox
Subject: Re: Can't hear cracks - visual clues?
"Coffee Contact" <coffee@nb.aibn.com > wrote in message
news:wTroh.42186$cz.618240@ursa-nb00s0.nbnet.nb.ca...
>
> >>>
>>
>> How about smell? - Mike
>
>
> Have to agree with that, smell and taste being closely linked.
> Seems to me that
> this group places too much emphasis on technology and not enough on taste.
>
> Terry M
>
>

Technology may be discussed here more than issues of taste, but as others
have pointed out, taste is by its very nature subjective, hard to
standardize and quantify, whereas technology is more straightforward and
repeatable. I think they are both important. A professional roaster such
as yourself who presumably roasts sacks of coffee every week is going to
develop a skillset not unlike the chef who can judge degrees of "doneness"
without having to make an incision in the filet or measure the temperature
of a souffle. That having been said, even professional chefs undercook or
overcook a steak or a piece of fish, if my own observations in restaurants
are typical. I've even been served souffles that were incompletely cooked
in a fine restaurant or two; had they put a thermocouple into the middle as
it cooked, I doubt that would have happened.

The typical home roaster who uses a cheap home roasting appliance, sometimes
cobbled together from such things as popcorn poppers and "Stir Crazys," who
has small stashes of 12 different green beans in the garage or basement,
maybe roasting each variety every 3 weeks, hasn't a prayer without some
level of "technology." This technology could be anything from an oven
thermometer to a $12 thermocouple with attached reader to something more
rekable. I've tried to make the point several times that this approach,
trying to roast 12 different beans in small batches and all of them
occasionally, is an invitation to mediocrity, but many people continue to do
this. For me, I'd rather have 1-3 different beans or blends I'm working
with a particular time, which certainly cuts down on variability since you
become more familiar with what you have.

Jim Schulman and myself have done several experiments in which we have tried
to "bridge" technology and taste. In the end, taste is the only thing that
matters, but how you get there in a repeatable way is not as simple as
listening to cracks and smelling the smoke coming off roasting beans.

ken




 
Date: 07 Jan 2007 21:47:38
From: Ken Fox
Subject: Re: Can't hear cracks - visual clues?
"Mike Hartigan" <mike@hartigan.dot.com > wrote in message
news:MPG.200b77f7ab30bf519898f1@newsgroups.comcast.net...
> In my iRoast 2, sometimes I can hear the cracks as plain as day,
> sometimes I can't hear a thing. Since it's a rare batch that doesn't
> taste really, really good, I'm assuming that my roasts are
> progressing normally, crack(s) and all. I was wondering - are there
> visual clues that indicate that the cracks have or are occurring?
> For example, if I see chaff flying, is it safe to assume that I've
> reached the first crack? What about when the beans double in size?
> Are there any visual manifestations that traditionally accompany
> second crack?
>
> --
> -Mike

Let's be honest here; cracks and other auditory cues in roasting are nothing
but a mediocre substitute for decent thermometry.

When I used to roast with cheap air roasters like my FR+ and Caffe Rosto,
there was a constant battle between what remains of my hearing in middle
age, and environmental noise, most notably fan noise from the roaster
itself.

I'm fortunate now to have a completely different type of setup, using a
modified 1lb sample roaster with a thermocouple that lies more or less in
the middle of the drum, or at least far enough from the sides that the
temperatures it reports are repeatable, even if not representative.

There are things that make beans less "noisy" as they roast, such things as
beans that are a little bit older, decaf beans, and maybe the way they are
processed (wet vs. dry and modifications thereof), plus how much humidity is
around where you store them. We are more or less stuck with these things
because they are what they are, unless we are going to decide to roast other
beans or maybe move.

If cracks have become, for you, unreliable as a way to monitor roast
progress, then I submit that you really have no choice other than to get
into thermometry, as least a bit. There are many ways to monitor roast
temperatures during a roast, everything from a stationary thermometer to a
rigidly mounted thermocouple and a fluke. You pays yer money and you takes
yer chances.

If you can't hear enough to make roasting decisions with your current setup
you are either going to have to change the setup (doubtful) or find some
other way of monitoring your roasts. Visual cues help but as far as I'm
concerned they are even less reliable than auditory cues as the appearance
of the beans 30 minutes after you roast them is apt to be very different
than when you terminated the roast. Things happen fast, a bit too fast, to
rely on visual cues unless all you want to do is distinguish between
incineration and a "cinnamon" roast.

Get a thermometer or a cheap thermocouple and figure out a way to get it
into a part of your roaster where the temperatures it measures have some
relationship to roast progress and are repeatable.

Unfortunately, I think this recommendation may be less useful for air
roasters than it is for drum roasters and most people reading this will have
air roasters. Oh well. And it won't be of any use to the dog dish/heat gun
people. Sorry.

ken




  
Date: 08 Jan 2007 07:18:40
From: Randy G.
Subject: Re: Can't hear cracks - visual clues?
"Ken Fox" <morceaudemerdeThisMerdeGoes@hotmail.com > wrote:

>"Mike Hartigan" <mike@hartigan.dot.com> wrote in message
>news:MPG.200b77f7ab30bf519898f1@newsgroups.comcast.net...
>> In my iRoast 2, sometimes I can hear the cracks as plain as day,
>> sometimes I can't hear a thing. Since it's a rare batch that doesn't
>> taste really, really good, I'm assuming that my roasts are
>> progressing normally, crack(s) and all. I was wondering - are there
>> visual clues that indicate that the cracks have or are occurring?
>> For example, if I see chaff flying, is it safe to assume that I've
>> reached the first crack? What about when the beans double in size?
>> Are there any visual manifestations that traditionally accompany
>> second crack?
>>
>Let's be honest here; cracks and other auditory cues in roasting are nothing
>but a mediocre substitute for decent thermometry.
>
>
>I'm fortunate now to have a completely different type of setup, using a
>modified 1lb sample roaster with a thermocouple that lies more or less in
>the middle of the drum, or at least far enough from the sides that the
>temperatures it reports are repeatable, even if not representative.
>
>Unfortunately, I think this recommendation may be less useful for air
>roasters than it is for drum roasters and most people reading this will have
>air roasters. Oh well. And it won't be of any use to the dog dish/heat gun
>people. Sorry.
>>[major snippage above]

As Ken stated, I agree that monitoring temperature can be an excellent
way to monitor roasts. I do think that it can work quite well for the
iRoast. Take a look at my review and you will see how I added a probe
to my iRoast:
http://home.surewest.net/frcn/Coffee/iRoast2.html

Use a "grounded" probe and locate it off to one side, away from the
direct air flow. The reported temps seemed to be quite consistent with
the correct temps for cracks...

Randy "cracks, but no pot" G.
http://www.EspressoMyEspresso.com




   
Date: 08 Jan 2007 13:44:18
From: I->Ian
Subject: Re: Can't hear cracks - visual clues?
On Mon, 08 Jan 2007 07:18:40 -0800, Randy G. <frcn@DESPAMMOcncnet.com >
wrote:

>"Ken Fox" <morceaudemerdeThisMerdeGoes@hotmail.com> wrote:
>
>>"Mike Hartigan" <mike@hartigan.dot.com> wrote in message
>>news:MPG.200b77f7ab30bf519898f1@newsgroups.comcast.net...
>>> In my iRoast 2, sometimes I can hear the cracks as plain as day,
>>> sometimes I can't hear a thing. Since it's a rare batch that doesn't
>>> taste really, really good, I'm assuming that my roasts are
>>> progressing normally, crack(s) and all. I was wondering - are there
>>> visual clues that indicate that the cracks have or are occurring?
>>> For example, if I see chaff flying, is it safe to assume that I've
>>> reached the first crack? What about when the beans double in size?
>>> Are there any visual manifestations that traditionally accompany
>>> second crack?
>>>
>>Let's be honest here; cracks and other auditory cues in roasting are nothing
>>but a mediocre substitute for decent thermometry.
>>
>>
>>I'm fortunate now to have a completely different type of setup, using a
>>modified 1lb sample roaster with a thermocouple that lies more or less in
>>the middle of the drum, or at least far enough from the sides that the
>>temperatures it reports are repeatable, even if not representative.
>>
>>Unfortunately, I think this recommendation may be less useful for air
>>roasters than it is for drum roasters and most people reading this will have
>>air roasters. Oh well. And it won't be of any use to the dog dish/heat gun
>>people. Sorry.
>>>[major snippage above]
>
>As Ken stated, I agree that monitoring temperature can be an excellent
>way to monitor roasts. I do think that it can work quite well for the
>iRoast. Take a look at my review and you will see how I added a probe
>to my iRoast:
>http://home.surewest.net/frcn/Coffee/iRoast2.html
>
>Use a "grounded" probe and locate it off to one side, away from the
>direct air flow. The reported temps seemed to be quite consistent with
>the correct temps for cracks...
>
> Randy "cracks, but no pot" G.
>http://www.EspressoMyEspresso.com
>
>
From the graphs on the page, the crack temps appear about 25F too
high.

I'd recommend putting the probe at the top of the chamber. Found that
location more consistent with less stairstepping and variablility with
location on both an iRoar and an FR.

Also use a bare bead TC for faster response.


    
Date: 08 Jan 2007 15:01:17
From: Ken Fox
Subject: Re: Can't hear cracks - visual clues?
"I- >Ian" <someone@nowhere.com> wrote in message
news:jfe5q25co29hcjvtt65fhgk7han8hdbor4@4ax.com...
> >>
>>
> From the graphs on the page, the crack temps appear about 25F too
> high.
>
> I'd recommend putting the probe at the top of the chamber. Found that
> location more consistent with less stairstepping and variablility with
> location on both an iRoar and an FR.
>
> Also use a bare bead TC for faster response.

Bare TCs are fragile. In addition, the actual numbers measured are a much
less important than their repeatability. My own thermometry setup, which
includes a sheathed probe permanently mounted in my sample roaster, read by
a fluke, reads consistently high, at least 10 degrees and more probably 15
degrees high. It doesn't matter at all because I've learned what the
numbers mean in the context of my roaster and my measuring equipment. Often
I will adjust the flame or terminate the roast based upon the thermometry,
without torturing myself over whether or not I heard the first few pops of
first or if 2nd crack was "rolling." My results are more consistent as a
result. The combination of a cheap digital stopwatch and digital
thermometry are unbeatable for roasting.

ken




     
Date: 08 Jan 2007 14:30:22
From: I->Ian
Subject: Re: Can't hear cracks - visual clues?
On Mon, 8 Jan 2007 15:01:17 -0700, "Ken Fox"
<morceaudemerdeThisMerdeGoes@hotmail.com > wrote:

>"I->Ian" <someone@nowhere.com> wrote in message
>news:jfe5q25co29hcjvtt65fhgk7han8hdbor4@4ax.com...
>> >>
>>>
>> From the graphs on the page, the crack temps appear about 25F too
>> high.
>>
>> I'd recommend putting the probe at the top of the chamber. Found that
>> location more consistent with less stairstepping and variablility with
>> location on both an iRoar and an FR.
>>
>> Also use a bare bead TC for faster response.
>
>Bare TCs are fragile.

Have not found that to be the case here. The bead protrudes barely
.050 from the end of its support tube and as the probe is shielded by
the chaffe collector, it's pretty well protected..

>In addition, the actual numbers measured are a much
>less important than their repeatability.

Agreed. However, I find it much easier to transfer profile data
between roasters if I know that bean x is going to hit 1st at 395F
alittle rather than alot.

>My own thermometry setup, which
>includes a sheathed probe permanently mounted in my sample roaster, read by
>a fluke, reads consistently high, at least 10 degrees and more probably 15
>degrees high. It doesn't matter at all because I've learned what the
>numbers mean in the context of my roaster and my measuring equipment. Often
>I will adjust the flame or terminate the roast based upon the thermometry,
>without torturing myself over whether or not I heard the first few pops of
>first or if 2nd crack was "rolling." My results are more consistent as a
>result.

I think you can enter a calibration offset on your Fluke to adjust the
displayed temperature to actual temperature.

[ I've done that for my two K TC in the HotTop and the one in the FR.
It's not that I needed to as they are all within 0.3F, but since I
have a grinder capable of submicron adjustment, seems foolish to let
such gross error go uncompensated ;-) ]

>The combination of a cheap digital stopwatch and digital
>thermometry are unbeatable for roasting.
>

Absolutely!

A missus that enjoys a cappa or two helps.

Good hearing helps a tad too ;-)

>ken
>

Ian