HomeRoast Digest


Topic: Roaster Design (57 msgs / 1242 lines)
1) From: Dan Bollinger
<Snip>
They
<Snip>
maybe).
<Snip>
response
<Snip>
make
<Snip>
I work empirically, too.  The "let's try it and see method works for me".
If nothing else it is faster, funner, and doesn't boggle my brain the way
algebra does.  So, just for fun, yesterday I mocked up a fluidized bed.  It
worked great.  The one pound of beans spouted with vigor, and rotated much
faster than my HWP with the fan on high.  If anything, it moved too fast and
need turned down, a simple thing to accomplish with either a damper or motor
speed control.  Here are the particulars:
Chamber:  6" ID, 6" high, with conical bottom (angle of about 30)
Blower:  (the exhaust on a small shop-vac) 6.8A motor/blower unit,
single-stage centrifugal, 112cfm (2" orifice)
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2) From: Ken Mary
It is much easier to reverse engineer existing roasters. Other people have
already solved most of the problems. Find a design you like then copy it or
*buy* one and adapt it to your needs. Make it better than the original. Most
of us do this anyway with soup cans or foil or controlling with a variac
etc.
--
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3) From: AlChemist John
Sometime around 07:35 7/28/02, Dan Bollinger typed:
<Snip>
It very well may be faster in some instances, but I find the 
math/calculation quite enjoyable.  There is almost nothing I like better 
than designing something from theory and numbers, and then seeing that the 
implementation actually works.
John Nanci 
AlChemist at large
Roasting and Blending by Gestalt
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4) From: Ed Needham
Did you get a picture of this Dan?  You are saying it is a configuration
similar to a Precision, but with a 30 degree angle to the sides?
Ed Needham
ed
**********************************************

5) From: Dan Bollinger
Ed,  It is a 6x6" cylinder with a 30 conical bottom.  A larger version of
the HW design.  It moves 1 pound easily.  There was too much air velocity
and volume. I think turning down the speed on the blower would take care of
both.

6) From: Rick Farris
Dan wrote:
<Snip>
Now you've got me really confused, Dan.  Is it a cylinder, or is it a cone?
What is the diameter of the top?  What is the diameter of the bottom?
-- Rick
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7) From: Paul Milne
This is a multi-part message in MIME format.
Hi again. I have been reading Dan and Ed going back and forth on their =
roaster projects.
Here is a little more info on how I am constructing mine.
First, for the top part of the roasting chamber, I bought a five inch =
diameter Coleman globe. Now, with the hot air blowing in from below, I =
needed to have some sort of 'cone' shaped bottom section. The purpose of =
the conical shape is to have the air blowing the beans up in teh middle =
and sliding back down the sides to be re-circulated by the jet of air =
blowing up through teh beans. 
I  found a five inch stainless steel canning funnel to do the job. It =
has a 1 inch high shoulder on top and then gently slopes down to a two =
in outlet, like a canning funnel. 
It is assembled like this. First, I needed a 'container' for this unit.  =
I found a small 5 1/8 inch diameter stainles steel pot, miraculously, by =
accident. It is only 5 inches in height as well. No handle, like a =
cylindrical little bucket.
I drilled a hole in the bottom of it large enough to just allow the 2 =
inch diameter bottom of the funnel to fit down through. So, the funnel =
now sits all the way down in the 'pot'. The top of the funnel is about 1 =
1/2 inches from the top of the pot. The glass globe is inserted into the =
top and sits directly on top of the funnel. The glass extends about  =
four inches above the steel pot and is MORE than adequate for viewing =
the roasting beans.
This comprises the roasting chamber.
On top of the glass globe goes the chaff collector that I am working on.
And of course, the heat source and blower goes below. I have ordered a =
suitable heat gun with a variable temperature range. It will have to =
have a modified fan motor drive. The one that comes with the heat gun =
only goes to about 20 cfm, and I need it variable up to 100.
The heat gun also has a thermocouple with an LED readout of teh =
temperature at teh nozzle. I will add a second identical thermocouple to =
insert intto the hopper to give a readout of the bean temperature =
itself.
After I get the heat source worked out I will purchase a Kitchen AID 3 =
speed blender as the thermoplatic CASE for this contraption.  I will =
'gut' the blender and install the heating element inside... and the =
roasting chamber fits perfectly up on top exactly where the glass =
blender hopper would go.
If you want to see what it will generally look like, you can see the =
'blender' here and imagine what I am talking about.http://kitchenaid.suresource.com/Itemdetail.asp?uid=2002072915082082&It=em=KSB3WH&edp=23524&itemcat=KSB3ZZ
Operation:
Place quantity of beans in hopper. FIRST turn on fan and create a small =
rising column of beans in the middle. Adjust airflow to quantity of =
beans being 'circulated'. THEN, turn on heater to desired temperature. =
You can alter the temperature as you are roasting to fit your roast =
profile.
After desired roast is obtained turn off heat and allow  ambient air to =
continue to flow to cool beans. The LED temperature indicator in the =
hopper will tell you how fast they are cooling. 
It will be pretty manual at first, but in the future I will work out a =
control system. 
Glass globe            $8
Funnel                    $20
Stainless steel pot    $7
Heat gun                 $110
Blender                    $90
All told, I will have a roaster that will be able to air roast up to =
about 3/4 pound at a time for under 300 bucks. There will be no need for =
a home roaster to do much more than this as the freshness of the roasted =
coffe will diminsh before I could use it. I just wanted something that =
could do at least half a pound with some degree of ability to change the =
roast profile. All those single pot size roasters are worthless.
Paul

8) From: Dan Bollinger
It is a 6" round hopper with 6" high, straight sides and sloping bottom to a
center hole.    Just like a Hearthware roaster.  Dan
<Snip>
cone?
<Snip>
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9) From: Gary Zimmerman
Paul, I am SO impressed (with anyone who can build anything).  Sounds like 
fun, and if it works, your coffee will taste even better than it otherwise 
would, because you have the pleasure and satisfaction of cobbling together 
the roaster yourself.
Paul Milne wrote about his hombuilt roaster
<Snip>
Remember the beans will lighten while roasting, so you might want/need to 
turn down the airflow or turn up the heat at some point while the roast 
progresses.
-- garyZ
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10) From: Gary Zimmerman
Gary Zimmerman wrote:
<Snip>
I meant they get lighter as they get darker.  I meant they get 
un-denseful.  I mean... oh, never mind.
-- garyZ
tecknickel righter
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11) From: Timothy A Reed
On Mon, 29 Jul 2002 13:06:37 -0700 Gary Zimmerman 
writes:
<Snip>
That's just so cool, it's worth repeating. :)
-Tim
In your heart you wonder which of these is true
The road that leads to nowhere
The road that leads to you
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12) From: EskWIRED
<Snip>
Sounds like a great, simple design.
<Snip>
will have to have a modified fan motor drive. The one that comes with the
heat gun only goes to about 20 cfm, and I need it variable up to 100.
Keep in mind that you will be heating 5 times the volume of air that the gun
was designed for.  Will it handle this volume, and still heat it up hot
enough?
<Snip>
speed blender as the thermoplatic CASE for this contraption.  I will 'gut'
the
<Snip>
fits perfectly up on top exactly where the glass blender hopper would go.
Wow.  That will be great.
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13) From: Ed Needham
I'm wondering about the blender case.  First, it is 'way' expensive, and
second, I bet it is not applicable to the temperatures you will get with a
roaster.  Imagine melting and cracking after the first roast (ka-ching...bye
bye $100).  Why not just use a cheap stainless steel 'goo-gaw' from Wal-Mart
or something.  Walk the aisles until you get an inspiration.  It'll be
cheaper than the $100 for a blender that will be trashed.
A used restaurant supply store will probably have a piece of worthless
equipment that can be purchased for next to nothing and be 'gutted'.
Probably restaurant grade stainless to boot.
Just my 2 cents worth.
Ed Needham
ed
**********************************************

14) From: R.N.Kyle
This is a multi-part message in MIME format.
WoW what a project, I sure would like to see some pictures or drawling =
of your coffee roaster, so far from what I've read it sounds real =
interesting, keep on engineering
Ron Kyle
Roasting in South Carolina
rnkyle

15) From: Paul Milne
This is a multi-part message in MIME format.
Thanks for the comments:
Gary: Yes, I already thought about the changing weight of the beans. =
Thank you for mentioning it though. I am sure there are things that have =
escaped my immediate notice.
Dan and Eskwired:  I plan to modify the heat gun. Principally, I am =
purchasing it for it's 'design'.  I will change elements of it to suit =
myself. The blower will obviously be insufficient. Most guns produce =
less than 20cfm.  As far as the heating elelemt in gun is concerned, it =
generates MORE than enough heat. They run to over a thousand degrees. =
This does NOT change because you blow more or less air past it. The =
blower only moves that HEAT away from the element to where it is needed. =
I have been in touch with several manufacturers of heating elements and =
fans to help me determine what is best to use. Most have NOT been very =
helpful. Please keep up with your comments. They help me with things =
that I may not have thought about.
Ed: I am not going to be melting the 'blender' case. I will insulate any =
parts that need it. The KitchenAid one best fits my design and that is =
why I chose it for 'ready' made use. I am trying to turn something out =
that does not have the appearance of a 'Rube Goldberg' Device..
Ron: When I am finished, I will make all the information available to =
anyone that wants it.

16) From: EskWIRED
This is a multi-part message in MIME format.
 > As far as the heating elelemt in gun is concerned, it generates MORE than
enough heat. They run to over a thousand degrees. This does NOT change
because you blow more or less air past it. The blower only  > moves that
HEAT away from the element to where it is needed.
Heat is measured in BTUs.  Temperature is measured in degrees.  If you were
to take your heat gun, and attempt to heat up your house with it, you would
never get the house up to 1000 degrees, because it puts out insufficient
heat, even though it can put out enough to get a small area up to 1000.  In
your roaster design, you have a lot of volume to heat, and a lot of mass.
While the gun may be able to get a few cubic inches of air (weighing a
fraction of a gram) up to a high temp, it may still not have enough oomph to
get many cubic inches of dense beans up to 450.  Unless you take a long
time, and very little heat radiates away in the meantime.
The principle is the same as with gas grills:  Every one of them uses the
same fuel, propane, and every tank of propane burns at the same temperature.
Indeed, a low flame will burn at the same temperature as a big whooshing
flame.  But the big flame will heat more meat, faster.  Larger capacity
grills need more BTUs in order to get sufficient temperature in the bigger
space.   When you turn up the grill, the fire stays the same temperature,
but you have more of it.
Just some thoughts.  The gun may be totally adequate..

17) From: Gary Zimmerman
Paul Milne wrote:
<Snip>
Where's the fun in that?
  :-)
-- garyZ
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18) From: Dan Bollinger
This is a multi-part message in MIME format.
Don't forget, it isn't just the cfm that is important, but air velocity =
combined with static pressure that creates the fluid bed. i.e. A =
'whole-house' fan may be 20,000 cfm, but it won't lift a single coffee =
bean up in the air.  Heat guns are about 3000fpm and heat blowers are =
about 2000fpm.  This may help: www.masterappliance.com   
Dan
  Thanks for the comments:
  Gary: Yes, I already thought about the changing weight of the beans. =
Thank you for mentioning it though. I am sure there are things that have =
escaped my immediate notice.
  Dan and Eskwired:  I plan to modify the heat gun. Principally, I am =
purchasing it for it's 'design'.  I will change elements of it to suit =
myself. The blower will obviously be insufficient. Most guns produce =
less than 20cfm.  As far as the heating elelemt in gun is concerned, it =
generates MORE than enough heat. They run to over a thousand degrees. =
This does NOT change because you blow more or less air past it. The =
blower only moves that HEAT away from the element to where it is needed. =
I have been in touch with several manufacturers of heating elements and =
fans to help me determine what is best to use. Most have NOT been very =
helpful. Please keep up with your comments. They help me with things =
that I may not have thought about.
  Ed: I am not going to be melting the 'blender' case. I will insulate =
any parts that need it. The KitchenAid one best fits my design and that =
is why I chose it for 'ready' made use. I am trying to turn something =
out that does not have the appearance of a 'Rube Goldberg' Device..
  Ron: When I am finished, I will make all the information available to =
anyone that wants it.

19) From: EskWIRED
<Snip>
combined with static pressure that creates the fluid bed. i.e. A
'whole-house' fan >>may be 20,000 cfm, but it won't lift a single coffee
bean up in the air.  Heat guns are about 3000fpm and heat blowers are about
2000fpm.  This may help: >>www.masterappliance.com
Wow.  That's a great site.  They have some great explanatory stuff which
combines concepts in a nice way.
This "Heat Blower" looks mighty interesting:http://www.masterappliance.com/masflow.htmlThe 1680 watt model might be just about perfect.  Then again, it might work
just as well to get a 1680 watt hair dryer, and to mate it up to a good
squirrel cage fan.
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20) From: Dan Bollinger
I looked at the heat blower, too, but worry that the fan doesn't develop
enough pressure.  It is only about 2.5A, which is the same as the HWP's fan.
You might not be able to move one pound of beans, which is my goal.
I think the heating element in the larger MA heat blower would be just about
perfect and will consider this for my heat supply.  But, I think I'll use
another fan.
Still, it is worth a try. You'll want to check when it arrives to see if it
spouts beans.  If not, you can always send it back.
Heat guns start at 500, hot enough to ignite wood and paper, even melt
solder.  A hair dryer never gets this hot since it would also ignite hair!
Sivetz says you need 530 air for the roasting stage.

21) From: Catherine Marley, M.D.
EskWIRED wrote:
 
<Snip>
You might look into dog hairdryers.  They are heavy duty, and move a lot of
air.  Speedy makes a nearly indestructible unit, and you can get a 240 volt
version that really packs a tornado punch.
-- 
For the conservation of the Tibetan Lhasa Apso,
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22) From: EskWIRED
<Snip>
Wow.  530!  I didn't realize.
I've seen hair dryers with outrageous wattage ratings.  I think I saw an
1850 watt one once.
The heat element looks like just a standard spring-like coil.  I wonder if
heat gun elements are more efficient than
hair dryers.
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23) From: Ed Needham
If you are 'bent' on using the blender body, why not contact Kitchen Aid and
tell them you need a replacement body and pay only for the body?
As to the heat and air volume/speed, if the air flow is high, the air temps
are lower.  Slow down the air, and it heats up really fast.  It will not stay
the same.
Ed Needham
ed
**********************************************

24) From: R.N.Kyle
This is a multi-part message in MIME format.
Paul thanks for the come back, and I'm looking forward to hear about =
your progress, good luck.
Ron Kyle
Roasting in South Carolina
rnkyle

25) From: Rick Farris
Paul wrote:
<Snip>
Err...yes, in fact it does.
<Snip>
Don't confuse "heat" with "temperature".  In electrical terms, heat flow is
equivalent to current, and temperature is equivalent to voltage.  Blowing
more air past your heating element is the same as placing a higher load
(more current) on a voltage source.  Unless that voltage source has a source
impedance of zero, the voltage will drop proportionally to the increase in
current.
-- Rick
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26) From: Dan Bollinger
<Snip>
If both are using nichrome wire, then both are equally efficient at turning
electricity to heat.  By altering the diameter of the wire and the length,
you can create heating elements with varying temperatures and wattages.
There are companies that will make you a coiled nichrome heating element to
your specification.  I may do this for my roaster.
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27) From: Catherine Marley, M.D.
<Snip>
<Snip>
In a unit that combines two elements, a heat source and a blower, the desired
temperature of the necessary velocity and quantity of air is the issue. The coil
transfers heat to the air at a rate determined by the temperature of the coil
and the heat capacity of the air.  The final temperature of the air will depend
on the amount of heat transferred to a given quantity of air.  More air, lower
temperature, same amount of heat.  
We are concerned, in a roaster, that we are delivering enough heat to the bean
to cause a specific increase in internal temperature of the bean.  Thus we now
have a third factor, the mass of the bean to be heated by the heat carried by
the air.  But the air must be hot enough (temperature) to deliver enough heat to
the entire mass of beans to raise the internal temperature to a given level
within a specified time.  Again we have yet a forth element - time. Coil heat
production, transfer to a quantity of air, transfer to a mass of beans over a
given time, are the essential elements of an air roaster.  Fail to balance any
one of these, and you just have a useless fire hazard.  Best of luck to you
would be inventors.
-- 
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28) From: EskWIRED
<Snip>
Why do that, rather than buying a cheap compact 1850 (or whatever) watt hair
dryer?
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29) From: Dan Bollinger
Two reasons.  First, a hair dryer will only produce about 300, not enough
to roast coffee.  Second, in order to 'spout' one pound of beans I'll have
to use a stronger blower than the one they come with, the additional flow of
air will cool this temperature down.  Want to test this?  Just put a dozen
beans in a pyrex bowl and try to roast them.
<Snip>
hair
<Snip>
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30) From: EskWIRED
I was thinking of taking the nichrome wire out of a hair dryer, rather than
using the body or the blower.
Are you saying that two different nichrome wire elements of the same wattage
can have two different
temperatures, all else being equal?  If so, then there is something
important that I'm confused about.
It seems to me that if they are converting the same amount of electricity
into heat (by having the same wattage) and if they are doing so at the same
efficiency, then they must be putting out the same amount of heat.  So all
other factors being equal, they would be at the same temperature.  What am I
missing?
<Snip>
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31) From: Dan Bollinger
<Snip>
than
<Snip>
wattage
<Snip>
same
<Snip>
I
<Snip>
You are confusing temperature with energy.
Amps x Volts = Watts, which is a measure of work or energy.  Heat is
measured in WattHours, calories or BTU. It is Work over a period of Time.
"Amount of Heat" is a lay term that may mean temperature, watts or BTU
depending on who is talking and the day of the week.  ;)
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32) From: EskWIRED
<Snip>
So if the two heating elements are each drawing 1850 watts and are of equal
efficiency, then it seems to me that they would each produce comparable
BTU/hour.  All other things being equal, how is one at a different
temperature than the other?  Why would the 1850 watt heating gun element
measure at 1000 degrees, while the thrift shop 1850 watt hair dryer element
measures at 300?
How the heck do they do that?
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33) From: Dan Bollinger
<Snip>
equal
<Snip>
element
<Snip>
Boy, now you got ME confused!  I'm going to try and find an engineer who can
better explain this, but it will take some time.  In the meantime, here are
the factors which my help.   What you don't know is the length and diameter
of the nichrome wire nor the cfm in your two units.  One may have a fat,
long wire that barely glows (low temperature) and a high cfm blower cooling
the element and making 300 output while drawing 1850W.  The other may have
a skinny, short wire that glows brightly ( high temperature) and a low cfm
blower that barely cools the element and making 1000 output while drawing
1850W.
I know, it doesn't make sense does it?  Think of it this way.  One heating
element is concentrating the heat in a smaller area which increases the
temperature, but of course the wattage remains the same.
Think of a garden hose nozzle.  You can adjust it so it sprays an intense,
hard-hitting spray in an area less than one square inch, or adjust it to
cover 1000 square inches with a soft rain-like pattern.  However, both are
consuming the same gallons per hour.
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34) From: Christian Wiedmann
On Wed, 31 Jul 2002, EskWIRED wrote:
<Snip>
It depends on how much air each element is heating.  If one element is heating
twice as much air, it will only raise the temperature half as much.  Here's a
piece of trivia: one BTU is the amount of heat required to raise 1 cubic foot
of air 55 degrees Fahrenheit (or 55 cubic feet one degree).
The other complicating factor is that the 1850 watt rating may include the fan.
	-Christian
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35) From: Rick Farris
David wrote:
So if the two heating elements are each drawing 1850 watts and are of equal
efficiency, then it seems to me that they would each produce comparable
BTU/hour.  All other things being equal, how is one at a different
temperature than the other?  Why would the 1850 watt heating gun element
measure at 1000 degrees, while the thrift shop 1850 watt hair dryer element
measures at 300?
How the heck do they do that?
That's been explained a couple of times so far, Dave.  I'm perfectly happy
to give it another shot, but first, why don't you acquaint us with your
technical background so that we can direct our efforts in a direction that
may be helpful to you?  Obviously you didn't take thermodynamics in college,
do you have any electronics background?  Basic physics?
-- Rick
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36) From: Rick Farris
Dan wrote:
<Snip>
It's even simpler than that, Dan.  The exact same heating element, drawing
the exact same current and generating the exact same BTUs will have a
temperature proportional to the air volume blowing past it.
That's why an 1850W hair dryer only gets 300 degrees (not even that hot,
actually, I seem to remember 70C or about 160F.) and the 1850W heat gun gets
1000 degrees.  The hair dryer is much higher air flow.
-- Rick
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37) From: EskWIRED
<Snip>
Ok.  So Dan's explanation seems plausible, but Rick's explanation is the one
I had always thought was correct.
But this page seems to indicate that Dan might be right:http://www.wiretron.com/nicrdat.htmlFor a given wattage, the wire temp can be altered significantly, by varying
the gauge.
But I wonder if each will still be producing the same amount of heat,
despite the differences in temperature.
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38) From: Dan Bollinger
Rick,  Air flow is certainly one of the factors altering temperature --
which I mentioned btw -- but not the only one.  If one element has a larger
surface areas it will spread the heat over a larger area, thereby reducing
temperature even though both are the same wattage.  I'm afraid I didn't
explain all this very well in my earlier post.  Dan
<Snip>
gets
<Snip>
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39) From: Catherine Marley, M.D.
EskWIRED wrote:
<Snip>
It seems to me that a person who asks the same trivial question, and receives
more than 10 answers, but still persists in belaboring the same point must be
trolling for something.  
-- 
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40) From: Dan Bollinger
<Snip>
heating
<Snip>
Here's a
<Snip>
foot
<Snip>
More Trivia: A British Thermal Unit (BTU) is defined as the amount of heat
required to raise one pound of water one degree fahrenheit.
<Snip>
fan.
Yep!  Nameplate wattage or amperage ratings are ALWAYS the total electricity
the unit draws, not just one component.   Figure 0.5A for a shaded pole
motor in a heat blower, 2.5A for a small universal motor like in the HWP,
and 5.3-6.3A for a Shop-Vac.  I have no idea what the amperage is for the
motor in a hair dryer.
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41) From: Ted Kostek
There seems to be a little confusion about the difference between heat and
temperature.  I always find that a good equation helps clarify things.
q_in = c*m_dot*change_in_T
q_in			the (rate of) heat added in watts
c			the heat capacity of the "stuff" (physical property)
m_dot			mass flow rate
change_in_T		change in temperature
From this eqn, it's clear that higher mass flows lead to lower changes in
temp; the heat gets spread out over more mass.  So if you know the wattage
of the heater and flow rate of the air, you can find the temp rise of the
air after you look up the heat capacity.
Note you have to know how much juice is going to the heater and how much to
the motor.  An 1850 device isn't dumping all that into the heater (not that
I know of anyway).
On the thicker gauge wire,
q_out = h*A*T_diff
q_out		rate of heat transfered (watts)
h		convection coeff: depends on flow rate, materials, shapes; sorta fudge
factor
A		surface area
T_diff	T_wire - T_air_ambient
So if you increase A (thicker wire) while keeping others constant, then
T_diff goes down, and the wire gets cooler.
tmk
--
Ted Kostek
765 494 2146 (desk)
765 494 1489 (engine room)
765 494 0787 (fax)
"Always keep in mind that your own resolution to succeed is more important
than any other thing."  Abraham Lincoln
<Snip>
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42) From: Ken Mary
The heat comes from the electricity. But you must push enough air through 
the element so that it will not burn up. The element will be much hotter
than the air that passed over it. The efficiency of this heat transfer will
tell you how much air you need to maintain the wire temp below its maximum
and how hot the air will get.
This problem has already been solved. Just take a popper or other roaster
heating coil assembly and measure it. This is reverse engineering. You can
reduce or increase airflow around the popper mfr's design point but at the
risk of burning up the wire or not having the air hot enough to roast coffee
or not having enough air to mix the beans.
You do not have to reinvent the wheel. You already have one solution in your
hands. If you need a higher temperature, but if reducing airflow to obtain
this temperature will not mix the beans, then you must shorten the element
to increase the power (wattage) while maintaining the higher airflow needed
for mixing the beans and cooling the wire. There is a "family" of solutions
that will work, but be careful not to stray too far.
--
----------
<Snip>
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43) From: Dan Bollinger
Thanks, Ted!  My one year of engineering (before I went into Design) doesn't
take me very far.  I'm going to print these equations off for later use.
Dan
<Snip>
to
<Snip>
that
<Snip>
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44) From: Angelo
Cathy,
Let's look at the positive side. This thread has cured my insomnia....
Ciao,
Angelo
<Snip>
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45) From: Ed Needham
The correct formula is E=Mc2.  E =Energy, M=mass, c=speed of light, 2
=squared.
Now.  If the mass of the beans is hit with a low light/heat from an
(infra)red light source, then the roaster configuration needs to be square,
or E is wasted.  If, though, the light/heat source is higher (more E), then
it will glow whiter and hotter.  With that, the beans roast properly and
become light, the masses are happy, and the caffeine is converted to energy.
Basic Physics.
Ed Needham
ed
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46) From: Simpson
As understood and explained by a psychologist.  8^)
Ted, who once, when he was v-e-r-y young, tried holding on to heavy milk
jugs full of water so he would sink to the bottom in the pool. It was an
eye-opening experience. Now I, too, am a psychologist. I know my limits,
Simpson

47) From: Ed Needham
I almost changed my major in undergrad to a double major in Psych and
Physics...Isn't that a hoot!  Took two physics classes to fulfill my math
requirements (tested out of Finite), then went on to take several more
physics related classes because I liked them so much.  I enjoyed my physics
classes way more than the boring undergrad psych.
Ed Needham (wishes he were a psychologist...just a lowly masters
therapist...emphasis on 'pist'.)
ed
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48) From: Ryuji Suzuki -- JF7WEX
From: "Ed Needham" 
Subject: Re: +Roaster Design
Date: Thu, 1 Aug 2002 23:56:16 -0400
<Snip>
I haven't followed this thread but one thing here...
What about neuropsychopharmacology (of caffeine)?
--
Ryuji Suzuki
"I can't believe I'm here.
People always say that I'm a long way from normal."
(Bob Dylan, Normal, Illinois, 13 February 1999)
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49) From: Ted Kostek
Let me just point out that 1 BTU/hr = 0.29 watts.
Watts and BTU/hr measure exactly the same thing, just with different units.
Just like my height is 6'1" = 1.85 m.  Watts and BTU/hr tell the rate of
energy transfer.
tmk
--
Ted Kostek
765 494 2146 (desk)
765 494 1489 (engine room)
765 494 0787 (fax)
"Always keep in mind that your own resolution to succeed is more important
than any other thing."  Abraham Lincoln
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50) From: Dan Bollinger
<Snip>
Simpson, who knows better and fills his jugs with colored water cuz he knows
he'll sink to the bottom then!  Me?  I've only studied a little psychology
(mostly Adler who is very practical) so I haven't become quite as dumb and
fill my jugs with iced coffee (my attempt to keep this OT) so we can all
have a coffee klatch (sp?) at the bottom of the pool.  :)   Dan
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51) From: Dan Bollinger
Interesting, Ed,  I began in engineering at Purdue and had to take the
'weed-out' course Physics 152.  I understood every concept experientially
having spent my youth around farm, construction and industry machinery.  I
even tutored students who ended up getting A's!  I barely got a D.  I just
couldn't get my mind around the math and science of it.  Changed my major to
Art & Design and immediately got straight A's!  Later, took a Physics for
Non-Majors and loved it!  Part of me wishes I'd gone into psychology,too.
I'm a student of Adler and teach weekend workshops, counselor to my friends
and family, so I've managed to get a taste of helping people with their
problems.   Dan
<Snip>
physics
<Snip>
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52) From: Dan Bollinger
Right.  BTU is energy used over time.  By dividing out the time in the
formula you give you reduce it to energy, which is what Watts are.  It is
easier to see this in the alternate formula (and the one used in my
Machinery's Handbook):
1 BTU = 0.29 WattHours.   WattHours is what the meter on the side of your
house measures.  It is a unit of how much energy you used, not the rate you
used it at.
hope this helps clear things up!  Dan
<Snip>
units.
<Snip>
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53) From: Ed Needham
I was on a roll way back in my undergrad era, and tried, if at all possible
to write papers on caffeine if at all possible.  I had compiled a database of
research articles and would change the topic, but still write on caffeine.
I did papers on how caffeine affects different neurotransmitters throughout
the body, how caffeine affects slow twitch and fast twitch muscle
responses...even how caffeine affects productivity.  I never used a paper
twice, but I sure regurgitated old information a hundred ways.
The effects of caffeine on the body are so interesting.
If this message is incoherent, it is because I am higher than a kite on
Tylenol 4 pain meds.  I had eye surgery this morning to repair a detached
retina (yuck).  I had a previous surgery on the same eye back in 98, but this
time it's on the other side of my eye.  I'll be OK, but I need to lay in a
particular orientation for a few days so a gas bubble injected into my eye
can press the retina back in place.  I should be lying down now, but I'm
hooked on newsgroups and the homeroast list and just had to see what's going
on.
I'll be off from work a week or so, and then back in the saddle full force.
Ed Needham
ed
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54) From: Dan Bollinger
Ed,  Sorry to hear that you are down.  Get well soon, OK?  Dan

55) From: EskWIRED
 I had a previous surgery on the same eye back 
<Snip>
Hey - Get well soon!
<Snip>
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56) From: R.N.Kyle
I guess we can't see eye to eye now, but mabey after you recover, get well
soon.
Ron Kyle
a coffee roaster from South Carolina
rnkyle

57) From: Ed Needham
We can see eye to eye, but not eyes to eyes .  
Ed Needham
ed
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