HomeRoast Digest


Topic: The tale of the second roast (42 msgs / 1215 lines)
1) From: Benson Wills
 
Hi list,
I just received a Precision roaster from SM along with their coffee 
sampler. For the first roasting, I chose a Nicaraguan bean that, 
according to the great notes at sweetmarias.com had an interesting 
"woodiness".
I stopped the roasting too soon, after hearing what I thought was the 
first crack. The ground coffee looked similar to red oak shavings.
The second roast was much more interesting. Saturday just before lunch, 
I decided to roast some Sumatra Mandheling DP and invited my wife to 
watch. Since the machine, along with the web site notes, knows more 
about roasting than I do, I set the dial to 7 and let it rip.
After opening all the windows in the house and fanning the smoke alarms 
with brooms ("It looks burnt! Don't you think it's burnt? It sure looks 
burnt to me" my wife said as she tried to make sure the cat hadn't 
perished from all the commotion), I decided that future roastings would 
have to be done outside or in the basement.
The Sunday air in the house is decidedly less pungeant. The Sumatra 
beans are a gorgeous dark and oily looking brown. The brew, I told my 
wife, is as good or better than any specialty coffee shop cup I've 
tasted. And this is just my second try!
Since our kitchen doesn't have an adequate vent and I must go out or 
down to roast, could someone give me some information on how ambient 
"room" temperature affects roasting with the Precision? It may be 80 
degrees if I'm roasting outside, or 55 if I'm in the cellar in the winter.
Benson
North Wilkesboro NC
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2) From: floyd burton
I have a HWP and the roasts in summer with the ambient temps above 60F are
not to my taste.  I vastly prefer a longer roast, say with the ambient at
about 45F less and the HWP dial set at 6.5 to 7.  I roast to the very
beginning of the second crack and rarely see oil on my beans.  Longer roasts
supposedly make a less acid cup.  I love Yirg in the winter roasted at lower
temps but in the summer it is not drinkable-way too acid.
There is probably a lot of variance between roasters but a setting of 7 at
70F would char the beans in my HWP.  Tom suggests a setting of just under 5
I think on the web site for the HWP at "room" temp.  Check it out.  It takes
a long time to find the sweet spot for each bean variety.  I continue
roasting the same bean variety recording time, color and smell till I get it
where I want the roast.  Some people like deeper roasting and less bright
flavor.  The most important variable I can detect is the crack.  Listen for
the first and after several minutes the second will probably start.  Oil on
the beans after a day is one clue you are into the second crack.  Also look
for small divots blown out of the bean-this is also a clue as to the second
crack having occurred.  You can roast them enough to char all of the oil out
of the beans.  That would make a lot of smoke though.  It takes at least 2#
of beans for me to find the sweet spot.
If you roast in the basement, the coffee roasting aroma will still permiate
your house.  For some strange reason females get quite territorial about
smoke.  Would suggest either rigging up a vent arrangement or roast in your
garage or on a porch.  Always watch your roaster during the roasting cycle.
Something can go wrong and you do not want to have to call the fire brigade.
Have a friend who roasts outside in Minneapols with a WBPI and gets good
roasts when the temp is well below zero.  If you roast.
Like everything else in life, all of this depends upon your taste and nobody
but nobody can tell you what tastes good.  The number of variables involved
in the hobby is mind numbing but fun.
Enjoy

3) From: Steve Shank
Benson,
It makes a huge difference. I roast outside and am getting a jumper to shift the roast range up. For example, I've roasted at a 7.5 setting which lasted 10min 30 sec. and gotten a vienna roast on a hot dry day, and roasted at 11 which went 17 minutes and gotten a dark full city, but less than vienna at around 67 degrees on a rainy day. Yes I was under cover, but the air was damp. For those of you who are wondering, yes I checked my voltage and it was at 120 on the nose.
Given the temperature, humidity, and different coffees, I am finding it quite complex to set the precision properly and get exactly what I want. I'm working on a computer program to store information on all my roasts, but since I want to track my Gourmet and my precision and soon my jumpered precision, it's getting a little harder than I imagined when I started.
You can always set it for too dark and then hit the cool button when it's the way you want.
*********** REPLY SEPARATOR  ***********
On 08/26/2001 at 8:52 PM Benson Wills wrote:
<Snip>
Steve Shank
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4) From: Don Staricka
 
At 10:56 PM 8/26/01 -0700, you wrote:
<Snip>
In my experience, it is impossible to achieve consistent results by 
roasting according to the dial settings. I always just set the dial to 
maximum and then press the cooling button when I want the roast to stop. I 
listen for the sounds of the cracks and monitor the temperature inside the 
roast chamber with a thermometer that Tom sells. When the temperature is 
right for a particular bean and I know how far I am past first crack or how 
far into second crack I stop the roast. I also measure the exact length of 
time of the roast and find that while it is normally consistent with past 
results it can vary as much as 3 minutes on days when the voltage is low. 
The beauty of the HWP is that you can very easily hear the cracks and you 
can very easily initiate the cooling process.
Don
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5) From: gerald allen green
Mr. Wills,
From the array of replies to your e-mail already registered here, you will see
how basically unscientific is the art of roasting coffee.  I agree with the
person who advised setting the HWP higher than you think you will need, then
keeping an eye on the roast and hitting the cool button.  I live in Southern
California, so I haven't the option of going to a much cooler place to roast,
but to my taste my roasts are just fine.  I don't need to lengthen the
roasting time beyond the ~8 minutes I can get here.  With most bean varieties
I find that I set the dial at around 5.1 to get a fairly dark roast but one
with no oil visible on the beans, either at the end of roast or later after
degassing.  Neither do I (or my wife) find the smoke objectionable; I put the
roaster under my range hood and turn on only one of the 3 fans in the
Vent-a-Hood, and a nearby smoke alarm has yet to go off.  If you keep a record
of the settings and time of roasting for each bean, you'll learn what's best
in your environment.  I must confess that the noise of the HWP makes detecting
first and second crack an unreliable criterion for me.  Best wishes for happy
roasting! --  Jerry Green
Benson Wills wrote:
<Snip>
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6) From: Don Staricka
 
At 10:54 AM 8/27/01 -0700, you wrote:
<Snip>
Detecting the sound of second crack over the noise of the roaster is a 
little difficult at first although hearing first crack should not be a 
problem since it is so loud. Although I now know what to listen for and 
have no trouble hearing second crack I have also observed that I can hear 
it more clearly if I step away from the roaster. I can hear second crack 
just fine from across the room.
Don
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7) From: cationic
In addition to sound and color, another indicator of the progress and status
of the roast is smoke. More precisely, the change in density, color, smell,
and visual appearance of the smoke that happens around the second crack. In
my roasts, the amount, color, and smell of the smoke increases abruptly a
few seconds into the second crack. Since I like dark roasts, this is a
useful indicator for me. (I realize that this may not be useful for lighter
roasts.)
Regards,
Rafael

8) From: Keith Parker
When I first got my HWP, I created a spreadsheet for keeping track of my
roasting logs.
Basically, I would write down the temperature every 30 seconds in one column. In
the "crack" column, I would put a "1" when I heard the first pop of first crack.
At each 30 second interval, as I recorded the temperature, if I had heard a
"pop" I would put a 1 or a 2 into the "crack" column. This resulted in my
becoming very good at being able to tell the different cracks.
I no longer use the spreadsheet, but it was a great learning tool in the early
days.
You can get it at my website:http://www.BeyondTheSecondCrack.comRIGHT-click on the link called: Roasting Log Sample and choose "Save Target As".
You'll get an Excel spreadsheet.
hth,
Keith Parker
|                                                       |
|Keith Parker .........................Solis 166 Grinder|
|San Rafael, CA ...................Daily single cup drip|
|415-507-0123.....................Weekend Hario Vacu-Pot|
|Keith ....Hearthware Precision|
||
                   ^                ^
                   |                |
                   |                |
                   |||
     |                                               |
     |  Visit my personal home roasting website at:  |
     |            www.BeyondTheSecondCrack.com       |
     ||
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9) From: Ed Needham
It seems like a variable resistor (potentiometer) could be added in place of
the small resistors used to modify the HWP roast temperature range.  If one
of those could be hacked in, seamless calibration would be possible to
achieve consistent roasts no matter what the ambient temperature.  Any
suggestions as to a mechanism to use?
Regards,
Ed Needham

10) From: coffenut
Don,
I'm going to try your method of backing away from the unit if my 48yr old
hearing will allow.  On my HWP, I've had a lot of difficulty hearing any
snaps with certain beans like the "Maui Kaanapali Moka".  At best, I've been
able to hear a single 1st crack and cannot detect 2nd at all with that bean.
On the other hand, with larger beans like the Mexican Loxicha, I can clearly
hear 1st (all through) and 2nd is pretty faint.  I'm thinking of using a
thermometer with the HWP to see if that will help as another tool/gauge of
roast level.  Thanks..
Coffenut  :^)
<Snip>
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11) From: John - wandering Texas
Ed,
	I've tinkered quite a bit with thermistors and I can share that it is a lot
easier to drop the pot across the resistor instead of series - the
comparative resistance doesn't give you much motion with the pot.  If you
were to mount it in that fashion, all you would then need is a couple of
wires that came to the exterior of the unit to clip the pot on - and
removing the pot would immediately restore the unit to normal.
John

12) From: coffenut
Ed,
I was talking with HWP customer service today and inquired about these
"jumpers" to alter the roast.  I was told that the jumpers only affect
(lower) the temperature and because of that, roast time is affected.  Makes
sense on the surface.  But, if the temperature is simply lowered (via
jumper) below what it should be, wouldn't the result is a longer (baked)
roast?  If the jumper delays the initial temperature rise, but still allows
the correct temp at a later time, I'd think that would be the way to go.
I'm just not sure what the jumper actually does to the overall roast on the
HWP?  Hearthware's engineer was out of the country and won't return for 2
weeks or I would have asked him today.
Coffenut  :^)
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13) From: John - wandering Texas
I'm out of the thread after this because I'm a FR operator - but if they
have jumpers, then they are changing the tap for the load resistor changing
the r+r1 in the series.  In which case a pot probably isn't going to change
much effectively.  It would depend on the direction of change with the
jumper, adding or removing resistance from the circuit.  And having said
that I'm going to go away for a long while
John - wondering why everyone applauded that

14) From: Ed Needham
Maybe I'm confused here (not the first time).  I am also confused as to why
you would recommend that a potentiometer would be used in addition to the
resistor.  If a potentiometer could be purchased that provided the range of
resistance required, couldn't the resistor be tossed?
I was suggesting to take the resistors out and use the potentiometer for the
variable resistance.  If one could be purchased in the range of the three
resistors that Hearthware supplies (and maybe a bit above and beyond) , then
it could vary the roast without having to manually change the resistors (as
some here have done).  Isn't a potentiometer just a variable resistor?
I'm not sure I understand your reference to the thermistor.  I don't think
changing the resistance settings would affect the thermistor, since it just
feeds temperature information to the chip.  The resistor controls the
heating element intensity.
Regards,
Ed Needham

15) From: John - wandering Texas
Ed,
	I was just basing it on my experience with the FR.  To get a pot with
enough current carrying capability I had to get a fairly large resistance -
but then I'm shopping in Texico and have to take what I can find.
	Now, honest - I'm off-line, powering down - its my birthday and the party
is about to begin.
	Peace, Joy and Good Coffee
			John

16) From: Ed Needham
Anyone know what the rating is on the three resistors that Hearthware
provides for the HWP?  I can check a local radio shop for a pot and make the
mod as a test.
BTW--Happy Birthday John!
Regards,
Ed Needham

17) From: john tortuga
The rest of us would be very appreciative of your
courage in doing the experimentation.  Please let us
know what you find out.
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18) From: Steve Shank
I have to assume it will shift the whole range upward by reducing the resistance. Curve would remain, but all temperatures shifted. It is a little difficult to figure out what the HP is really doing because of all their black box magic with Roast profile. My guess is that it's really a timer switch without any temperature settings whatsoever and the roast profile merely has it do hot more as the roast approaches the middle and end of the allotted time. When I say timer, I mean that when it starts it sees where the setting is, and then uses that to set it's time and roast cycle. This would explain the huge difference a few degrees of temperature variation makes.
*********** REPLY SEPARATOR  ***********
On 08/27/2001 at 6:40 PM coffenut wrote:
<Snip>
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19) From: Ed Needham
The HWP operates like this...
--The dial on the front 'only' sets the time of the roast.  It does this
through the chip at the beginning of the roast.
--The Thermister at the heat outlet feeds temps into the chip and when the
target temp is reached, it maintains that temp.
--The fan is controlled by the chip, and cycles off and on in response to
the input the chip receives from the thermister.
--The heat cycles off and on, controlled by the chip, in response to the
input received from the thermister.
So, controlling the heating element via resistors or a variable resistor
device should have an effect on the roast, but not interfere with the inner
workings of the chip.  The chip will still have the same target temp, and
will turn the fan/ heater on and off as it is programmed to do so.
You will essentially get a faster or slower heat ramp up to the programmed
target temp, depending on how the potentiometer is set.  My guess is that
the overall roast time will be changed due to the faster or slower period
the heater takes to get to the target temp.
Regards,
Ed Needham

20) From: Steve Shank
Ed,
I'm sorry, but I find your explanation very hard to believe. You seem to know what you are talking about, so I think I should believe you. Thus, a conundrum of sorts. 
The conflict is that I find it hard to believe, though I understand that it could be true, that a roast is taking place at a certain temperature, but varies by nearly 100% in time because of a 10 degree change in temperature external to the roaster. If my house is at 70 degrees and the outside temperature is 50, or it  is at 70 degrees and the outside temperature is 60, it doesn't seem so drastically different to me on the inside.
I have roasted 17 minutes and gotten a lighter roast than another 10 minute roast. How could the roast temperature be the same, or controlled in any significant way other than a shutoff when the coils themselves get too hot? Where is this heat outlet you are talking about? Is there really so much exposure to the outside temperature between it and the beans?
*********** REPLY SEPARATOR  ***********
On 08/28/2001 at 11:19 PM Ed Needham wrote:
<Snip>
i
Steve Shank
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21) From: John Blumel
On 8/29/01 1:27 AM, Steve Shank wrote:
<Snip>
I don't think I understand this critique in the context of the quoted 
message below. Was there more in the original message that I missed? Or, 
maybe I just need more coffee.
<Snip>
The 'heat outlet' referred to is, I believe, the opening from the base 
that the roast chamber fits over. Are you really getting 17 minute roasts 
with an HWP? What roast level? My roasts, even including the 5 minute 
cool cycle, don't approach that length. Of course, I'm roasting in temps 
that approach 90 degrees so maybe the answer to the final question is yes.
Re: the heat cycling on and off (see above and below). I'm not sure that 
this is actually a function of the HWP chip. My understanding is that the 
temp is controlled solely by the fan speed adjustments.
John Blumel
<Snip>
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22) From: john tortuga
I think that is exactly how it works.  I doubt if
turning the knob after the roast has started has any
effect.  I don't think its like toasters, which
believe it or not, I have been told often sense both
temperature and moisture.  You wouldn't think it would
be rocket science to have a roaster do the same. 
After all, its basically a high temperature toaster
for coffee beans.  Anyone ever experimented to see if
turning the dial after roast start has any effect?
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23) From: john tortuga
So you have the ability to control the rate at which
you get to target temp but from there on you have to
stay at that temperature.  Thanks for the input.
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24) From: Steve Shank
John,
I'm sure I only quoted what I imagined was critical. But yes, I roasted 17 minutes not counting the cooling cycle (22 minutes all together). I set it at the next to the last setting and then pushed the roast button again when the cooling cycle started at around 15 minutes. I'm sure that if it were 90 degrees, I would have gotten the same roast at 6 minutes or less. This leads me to believe that the heating temperature for the beans is not controlled. I can't believe we would get this much variation if the heat control were measuring and keeping the heat constant anywhere close to the beans. I am not out in the cold, but at maybe 68 degrees. I'm not sure I even believe that the fan changes according to the heat.
I'm not complaining about the HWP, though I prefer the Gourmet. I think it'll be fine once I jumper it to raise the temperature. I just am skeptical of the "computer chip", and "roast profile", and setting degree of roast instead of time, when 10 or 15 degree changes in external temperature create such a huge change in degree of roast at the same settings. The unit was designed for use indoors under consistent conditions. When the HWP support guy told me that, I said, "yes, I know. But that's not how I'm using it." He said, ok, we'll get it to work for you. They seem pretty responsive and it seems to be well built.
*********** REPLY SEPARATOR  ***********
On 08/29/2001 at 7:17 AM John Blumel wrote:
<Snip>
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25) From: john tortuga
My guess is that the sensor is attached to the metal
floor of the chamber.  Theoretically the design
engineer calibrated the machine with some assumption
about ambient temperature that would make a correction
to the measured temp to estimate the actual
chamber/bean temperature.  The further you get from
that assumption, the more the roaster gets off. 
That's why roasting with the setting at seven gives a
lighter roast at 40 degrees ambient versus 70 degrees
ambient.  I can see how the variance between that
metal plate directly over the heat source versus the
air in the glass chamber could be huge.  The chamber
is not insulated in any way.
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26) From: Henry C. Davis
I don't roast outside much so I never got around to it, but when I was
considering the issue I thought about doing what I do for my smoker,
wrapping heat proof insulation around the chamber (with a small peephole to
monitor) to limit the effect of ambient temp on the roast chamber and the
difficulty of raising cold air from the intake to hot enough air to roast.
It make sense the sensor would be off if the outside temp is rather low and
the sensor is near the heat unit.

27) From: John Blumel
On Wed, 29 Aug 2001 10:16:46 -0700, Steve Shank wrote:
<Snip>
Wow!
<Snip>
You didn't say what roast level you were after but a 6 minute roast
time at 90 degrees would give me a Full City to a light Vienna roast
with most beans. What was your ambient temperature? (68 degrees I see
below) It should be interesting to see what sort of roast times I get
when it's 40 degrees in the dead of winter here.
<Snip>
Following are the claims made by Hearthware on their Web site:
  "...Patented thermistor control method combined with motor 
   speed control to ensure roasting consistency... ...3-speed 
   air flow and heating power controlled by micom chip."
They also list enough safety standard acronyms to start a small DoD
project,
  "UL,cUL,CE,TUV,GS,CB.JET,S,NOM,EMC,EMV"
but nothing about dousing the unit with water while plugged in. It is
interesting to note that there are six models for the Precision listed.
Maybe we should start comparing our experiences by model number.http://www.hearthware.com/roaster_compar.htmlJohn Blumel
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28) From: Thom Underwood
I don't know anything about electronics, however, I have used every model of
HP made (sometimes more than one of each) and will attest that ambient
temperature definitely effects roast time dramatically.  I live in San Diego
and roast outside so as you can imagine it is a fairly benign environment.
For the longest time I refused to admit to myself that differences in
ambient temperature of only 10 degrees (i.e. 65 vs. 75 degrees) could
possibly effect a roasting process that peaks at over 450 degrees.
To resolve the problem I simply place the HP in a cardboard file box without
the lid (though I have occasionally used a lid to ramp up the temperature
quickly) and roast away.  I first read about this simple solution on this
group and it works!  The box seems to stabilize the ambient temperature
around the HP and hence the roast characteristics.  My roasts tend to range
from 7 to 8-1/2 minutes to get a bit into second crack depending on the bean
and exactly what I am after.
Regards - Thom

29) From: John Blumel
On Wed, 29 Aug 2001 10:07:44 -0700 (PDT), john tortuga wrote:
<Snip>
It does not seem affect the roast time once the roast button has been
pressed. I'd guess that the chip reads the setting once when turned on
and then just goes into it's preprogrammed cycle. Some other posts in
the past seemed to indicate that the roast time is not infinitely
variable but that there are discrete settings that, if memory serves,
correspond to about a half a setting -- e.g., 4.75 to 5.25 is all
equivalent to 5 and 5.25 to 5.75 is all the same as 5.5.
John Blumel
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30) From: John Blumel
On Wed, 29 Aug 2001 11:01:28 -0700, Thom Underwood wrote:
<Snip>
So it sounds like I need to get a refridgerator with a glass front and
put the HWP inside to roast in the summer. Of course, it's going to be
difficult to hear the cracks in there.
John Blumel
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31) From: Steve Cat
 
FWIW I have no technical expertise in this area so I'm happy to express and 
opinion.  If the circuit you are modifying is a timer, I would assume that 
all you would get are longer or shorter times with the dial position being 
the same.  In other words a setting of 7 on my machine gives me about 9 
minutes roasting time.  Adding a resistor might make that 7 11 minutes but 
moving the dial to 9 would still get me 11 minutes and I wouldn't have to 
fool around with rewiring.  To me if you wanted a slower or faster temp ramp 
up you would have to modify the amount of electricity going to the heating 
coil, not to the timer.  I would assume that the chip target temp is 
unmodifyable.  My guess is that the roast profile would change greater with 
changes in ambient temperature and also possibly wind (to add another 
variable) or even possibly sun or shade, or even humidity (I think I'm going 
off the deep end!).  In fact I see greater differences roasting outside with 
the same ambient temperatures indoors (i.e.) when its 72 outside and inside, 
than when its 72 inside one day and 80 inside another day. Of course then 
again it could me magic or aliens.  Seriously my HWP is fairly consistent 
roasting inside and somewhat more inconsistent outside, enough so that I 
need at least a 1/2 notch more outside to get shiny black oily beans.  The 
advantage is that if I guess wrong I get somewhat under roasts when trying 
to attain a full city plus roast (yes I do leave it unattended outside 
because I don't want to hear or smell it I just look out the patio door from 
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32) From: coffenut
John,
From what I've read and experienced, the dial on the HWP is an electronic
version of the mechanical timer on the HWG.  On the HWP (as you pointed
out), the dial setting is read when the roast is started.  From that reading
the unit knows how much time to count before going into the cool cycle.  I
don't believe any of my roasters (HWP and ALP) have much real intelligence
about managing roast profiles once the roast button is pushed.  I think they
grab a few initial readings, start the roast and run the rest off a
pre-programmed routine.  Someone's analogy to a "coffee toaster" was about
right IMO, but I'm also not having to spend several thousand dollars to
roast coffee either.  All to say, I'm happy with what I've got and the
results.
Coffenut  :^)
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33) From: Steve Shank
I asked Hearthware the question. Rong said no. It looks when you click the roast button and further changes are ignored. If you turn it on with the wrong setting then just turn to the right setting, push the cool button, then push the roast again button and it'll see the new setting and use it.
*********** REPLY SEPARATOR  ***********
On 08/29/2001 at 10:07 AM john tortuga wrote:
Anyone ever experimented to see if
<Snip>
Steve Shank
Oregon Computer Solutionshttp://lists.sweetmarias.com/mailman/listinfo/homeroast">http://www.steveshank.comhomeroast mailing listhttp://lists.sweetmarias.com/mailman/listinfo/homeroast

34) From: gerald allen green
What Steve Cat e-mailed reminds me that in my e-mail on the 2nd roast subject I
didn't specify that bean type makes a tremendous difference what sort of roast a
particular setting will produce.  I just ordered some robusta from Tom, and I
was astonished that an even lower setting than I normally use on arabicas
produced a black, shiny roast instead of my usual dark brown non-oily roast.
--  Jerry Green
Steve Cat wrote:
<Snip>
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35) From: Ed Needham
Hi Steve,
The heat outlet is where the air exits the base.  If you take the roast
chamber off and look down into where the air blows out the top of the base
unit, there is a small thermister in the middle.  That is where the
temperature is monitored.  It sends electrical impulses back to the chip to
be factored into the programmed heat curve.
My experience with the HWP does not vary as much as yours with respect to
differences in ambient temperatures.  I have not done critical experiments
roasting in different temperatures, but many times I roast on my back porch
and ambient temperatures probably vary from 60F to 90F.  I roast inside
under the exhaust hood over my stove when temperatures are not comfortable
outside.
I think whatever difference there is in roast timing when outside air temps
vary is probably due to the heater's inability to maintain the temperature
in cold weather or to ramp up very fast in hot weather.  Heat loss through
the glass would also be significant in very cold weather.  The HWP has
proven to also be very sensitive to variations in electrical current.
Someone did roast curves for a HWP a year or so ago, but I've not been able
to find them recently.  They showed very consistent roasting temperatures
from roast to roast, comparing the first roast to subsequent roasts after
the roaster had warmed up.  It showed a ramp up to the programmed
temperature and then it maintained that temperature until the cooldown
stage.  They did no do comparisons with ambient temperatures as a variable
though.  That would be a great project for someone with a roaster linked to
a computer interface and a set of sensors.
Regards,
Ed Needham

36) From: Ed Needham
The heat definitely cycles on my unit.  I can tell by listening to minute
changes in the fan speed (not the typical cycling) and sometimes I can see
the lights in the kitchen dim slightly for a split-second.   Maybe mine has
a flaw that causes this to happen, but I don't think so.  Roasts are
predictable and consistent.
Regards,
Ed Needham

37) From: Ed Needham
Is anyone else getting this much variability in roasts when ambient temps
vary 10-15 degrees as Steve reports?  That's not my experience at all with
the HWP.  I do note small differences, but not enough to be concerned about,
even with a 30 degree range (from 60 degrees to 90 degrees ambient).
Steve. If you are getting 17 minute roasts, I'm sure you could get better
roasts with a new resistor to increase your heater temps.  My dark, oil
spotted roasts do not come close to 17 minutes, even if outside temps are
60F.
There is definitely a computer chip inside that controls the roast
temperature through the fan (and on my unit, through cycling the heater off
and on also).  Ask Hearthware tech support, or take it apart.  It's there.
That's the greatest difference between the Precision and the Gourmet, aside
from the roast chamber configuration.
Regards,
Ed Needham

38) From: Ed Needham
Turning the dial after the roast has started has no effect.
Regards,
Ed Needham

39) From: Ed Needham
Hi John,
What I was saying was that if you could put a variable resistor (I've not
done this yet) into the circuit instead of the fixed ones Hearthware uses,
the heater intensity could be controlled, which 'should' affect the ramp up
part of the temperature curve.  It's only a theory at this point, but I
think it's fairly obvious.
Regards,
Ed Needham

40) From: Ed Needham
Hearthware has told others that they have three separate resistors that can
be changed to increase or decrease the heater intensity.  They have nothing
to do with the timer.  My theory is that if a potentiometer (a variable
resistor) could be wired in as a substitute for the resistor, the heat
intensity could be variable and controllable.  I don't know what the
resistor values are, but it's a hack that I will try if I can find a
potentiometer with the correct range and values.
When I roast outside, I have not had to vary my dial settings more than a
half a click to get the roasts I like.
Regards,
Ed Needham

41) From: TFisher511
The only time I get roasting differences from 6 1/2 minutes to anything over 
9 is when I switch to the Alp. Have never seen anything like that in my 
Hearthwares. 
Well, maybe when the heater shut down and it was just the friction from the 
tumbling beans. When morning came and they still weren't done I set the 
Hearthware in the Florida sun to try the solar thing and......... never mind.
In a message dated 8/30/01 1:56:48 AM Eastern Daylight Time, 
cypsych writes:
Is anyone else getting this much variability in roasts when ambient temps
vary 10-15 degrees as Steve reports?  That's not my experience at all with
the HWP.  I do note small differences, but not enough to be concerned about,
even with a 30 degree range (from 60 degrees to 90 degrees ambient).
Steve. If you are getting 17 minute roasts, I'm sure you could get better
roasts with a new resistor to increase your heater temps.

42) From: Sherry
snip>  The heat definitely cycles on my unit.  I can tell by listening to
minute
changes in the fan speed (not the typical cycling) and sometimes I can see
the lights in the kitchen dim slightly for a split-second.   Maybe mine has
a flaw that causes this to happen, but I don't think so.  Roasts are
predictable and consistent.
Regards,
Ed Needham
I see my lights dim several times for a split second also when I roast. My
roasts usually go to 7-8 minutes for what I think is a full city. This
evening I roasted some Mexican Ficas las Chiapas outside where it is about
83  and 90% humidity. Surprisingly, the first crack was not heard until
about 5 minutes.I roasted it to about full city in about 9.5 minutes.
 With other types of beans I get to first crack at 3 minutes indoors with
the air conditioning.
I have been officially kicked outside to roast with the West Nile Virus
carrying mosquitos. Every member of my family, including my husband,
complains bitterly about the roasting "stink". Well, I guess at least my
kids will never forget the time when mom roasted coffee! What a wacko they
will say!
 
Sherry Morrison
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