HomeRoast Digest


Topic: RK Drum first roast thoughts and questions (49 msgs / 1600 lines)
1) From: True, Dennis W. FC1 (CVN69)
This is a multi-part message in MIME format.
Ok I got my Drum set up yesterday 
Uniflame at Walmart 48K BTU for $177.00 (normally $248.00) I like the
grill but since I have 4 burners do people adjust the burners
differently or do you keep them all the same through out the roast?
I did as stated to run through a trash batch and Whoops! I guess I
didn't have everything lined up right the coupler to the motor  I had to
keep holding the handle to prevent slipping so once I let the unit cool
down I unbolted and drilled some more holes adjusting the unit and
releveling (someone mentioned bearings where and any decriptives on what
I am looking for?)
Once I got it all set back up I tried my first real roast 3# batch of
some etho DP sidamo/guat/yemen the roast went well I was kinda running
blind didn't have a set profile to go by so I winged it here is what I
did
Preheat to 500
Put in drum  dropped to 425ish
Temp back to 450-475
11:45 First Crack
Temps rose to 525
13:15 start of second and pull
I have a pair of OVE' Gloves and I love them!!!! I was able to pull the
pin by hand with out an issue
The roast looked a bit odd to me not really evenly roasted I think I may
have been a bit cool 
All thoughts and ideas are welcome~~
Dennis

2) From: The Dunaways
This is a multipart message
I think it was Brett who suggested a broiler pan/drip bottom part like you =
would use in an oven.  It fits the footprint of the drum on the smaller dru=
m, so you may need to adjust for larger drum.  It evens out the heat, while=
 still letting it circulate. Helped my roasts get much more even. (And Bret=
t I probably forgot to say thanks after I tried that ... so thanks!)  And I=
 think I remember a few people using tiles?  I'm sure they will chime in or=
 it's in the archives.   I have the ove gloves and love them too.  I also f=
ound that a metal table to just rest the drum on while I'm pin pulling is a=
 nice addition.  It doesn't seem to hurt the table a bit.  Have fun!!!!
Janhttp://www.serendipityquilting.com<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
RK Drum first roast thoughts and questions
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I think it was Brett who suggested a broiler pan/drip bottom part like=
 you =
would use in an oven.  It fits the footprint of the drum on the smalle=
r =
drum, so you may need to adjust for larger drum.  It evens out the hea=
t, =
while still letting it circulate. Helped my roasts get much more even.=
 (And =
Brett I probably forgot to say thanks after I tried that ... so thanks!)&nb=
sp; =
And I think I remember a few people using tiles?  I'm sure they will c=
hime =
in or it's in the archives.   I have the ove gloves and love them=
 =
too.  I also found that a metal table to just rest the drum =
on =
while I'm pin pulling is a nice addition.  It doesn't seem to hurt the=
 =
table a bit.  Have fun!!!!
 
Jan
http://www.serendipityquilting.=com
 

3) From: Eddie Dove
Dennis,
My bearing setup is an ad-hoc implementation (read as needs
improvement) of what is mentioned in the following thread:
http://www.coffeegeek.com/forums/coffee/homeroast/271029#271029Read it to the end and the part numbers are given.  It is a good
thread and Ron Kyle participated in it as well.  The rollers aren't
essential, but I have a hearing impediment and wanted to work as much
noise out of the roaster as possible to ensure being able to hear the
cracks, which is not a problem.  One could also use Brett's Method of
just stopping the rotisserie momentarily with the on/off switch.
On the recommendation of Ed Needham, I use these as a heat diffuser; I
really like them:
Corning Hot Blocks for Gas grill temperature control 4984778
Char-Broil 2184778  $19.99http://buyitnow64.stores.yahoo.net/cohotblforga.htmlEddie
On 7/17/07, True, Dennis W. FC1 (CVN69)  wrote:
<Snip>
-- 
Vita non est vivere sed valere vita est
Roasting Blog and Profiles for the Gene Cafehttp://southcoastcoffeeroaster.blogspot.com/

4) From: Randall Nortman
On Tue, Jul 17, 2007 at 07:24:50AM -0500, Eddie Dove wrote:
<Snip>
I don't know anything about gas grill drum roasting, but I think I
have a cheaper solution.  For baking hearth breads in my oven I used
to line a shelf with unglazed quarry tiles, about 1/4" thick.  They
hold and even out heat pretty well, and you can leave a small space
between them for air circulation if you like.  I picked some up in the
floor tile section of a Lowe's hardware store for a whopping $0.77
each (6" square).  Make sure you get UNGLAZED quarry tile, as the
glazed stuff might contain lead, and you don't want that anywhere near
cooking appliances or anything you're going to be ingesting.  (Well,
that was more important for bread baking, since I was baking directly
on the tiles, but better safe than sorry, right?)

5) From: Rich Adams
I use a 1/2 inch steel shaft and a pair of 1/2" ID bearings from Ace 
Hardware to support and rotate my RK.
The bearings rest on the original rotisserie support brackets in a small 
groove I dremeled.
After 1.5 years of roasting 4 - 5 batches per week, one bearing started to 
squeak but one drop of oil took care of that.
The 1/2 inch steel shaft was very tight going through the 1/2 inch square 
tubing down the center of the RK, in fact I had to pound the drum down the 
shaft, so there was no need for the drum to be "attached" to the shaft, 
ymmv.
I also use the vented tray of a broiler pan as a heat diffuser.
Somewhere I have pictures, ping me offline if you need 'em.
Respectfully,
Rich Adams

6) From: Les
An interesting thread!  You need to be careful about adding too much heat
retaining media to your RK set-up.  You do want to be able to adjust the
heat in the chamber.  I went back to a simple 3 inch metal defuser, and like
the control I get.  I have a two burner setup and always keep them even.  I
don't know about a 4 burner setup.  I would say try to keep them even and
play around!
Les
On 7/17/07, Rich Adams  wrote:
<Snip>

7) From: Eddie Dove
Dennis,
Les, reminded me ...
I have a 4-burner, 48,000 BTU grill.  With a preheated grill, if I
want to start the roast at about 300F and keep it there for 2-3
minutes (depending on the bean), I have the middle two burners on low
and the outside two burners off.  When I am ready to ram the heat up,
all of the burners get turn on and are set to the same setting, which
is dependent upon the rate of rampdesired.
When I want to dump some heat right at 1st crack, I turn the ends off
and set the middle burners back to low.  I can then raise the hood
just a tiny bit so the the motion of the drum will drive out some of
the heat and drop to the temperature I want.
Between batches, depending on whether I want to start with a hotter or
cooler environment, I may leave the lid open whilst I handle cooling
and preparation of the next batch.
I am sure others can comment on my process and invite constructive instruct=
ion!
Hope this helps.
Respectfully,
Eddie
-- 
Vita non est vivere sed valere vita est
Roasting Blog and Profiles for the Gene Cafehttp://southcoastcoffeeroaster.blogspot.com/On 7/17/07, Les  wrote:
<Snip>
ike
<Snip>
 I
<Snip>
l
<Snip>
 to
<Snip>
re
<Snip>
the
<Snip>

8) From: Homeroaster
I use the perfed ceramic tiles, and I like the fact that they allow a lot of 
convection and radiation heat transfer.  When I tried using solid metal 
pans, and once, even a big thick griddle, the result was a significantly 
longer warm up time, longer roast and wasted time and propane, and the roast 
wasn't as good.
I tried roasting without any barrier and the roast was not bad, but not as 
good as it could have been.  *********************
Ed Needham
"to absurdity and beyond!"http://www.homeroaster.com*********************

9) From: Homeroaster
I use a 1/2"x6x6 red quarry tile under my thermometer and it always cracks 
after a few roasts.  I just leave it in there cracked and it doesn't hurt 
anything.
*********************
Ed Needham
"to absurdity and beyond!"http://www.homeroaster.com*********************

10) From: Brett Mason
Hi Jan,
Wish it were me - but a great idea from Jason Brooks....
.On 5/18/06, Jason Brooks  wrote: Justin,
.I've wondered about something like that coupled with a sparse coating of
.laval-style rocks.  Maybe knocked down smaller so they don't hit the
.chamber.  And maybe even an oven broiler pan top, already slit for heat
.transference.
.
.Jason.
.
. Jason Brooks
jbrookshttp://members.kinex.net/~jbrooks/blog/blog.htmlBest regards,
Brett
On 7/17/07, The Dunaways  wrote:
<Snip>
-- 
Cheers,
Bretthttp://homeroast.freeservers.com

11) From: The Dunaways
This is a multipart message
Hmm... well... now I'm thoroughly confused because that note is before my t=
ime here.  But that Jason is one smart guy.  So uhm... Thanks everyone?!   =
I apparently haven't enough coffee today... think I'll go pour more......=
Janhttp://www.serendipityquilting.com-------

12) From: Dennis & Marjorie True
Roast #2 is in the bag....
This time I did 6#'s of Brazil YB to a FC and I think I got the hang of 
it now it came out perfect!
I am going to get a heat diffuser and I am seriously thinking about the 
bearings even though I can hear the cracks easily I like the idea of 
making the rotation a bit smoother.
I used the middle 2 burners to adjust the heat and left the outside ones 
cranked up I have great control of the temps this way
Profile was
pre-heat 550
beans in 500
raised temps back to and held at 525
11:55 First Crack 
kept temp @ 500
temp rose to 530 just at Second started
Pulled the roast 15:45
Man I LOVE this roaster!!!
Dennis

13) From: RK
Rich are you sure you used a 1/2" shaft to drive thru the hollow tubing?. I 
know that the laser burned holes in the end plate are .515 which gives the 
1/2 OD hollow tubing enough space to slide thru the end plates and then tig 
welded in place. The inside of the hollow tubing varies in size but 
generally should be near 7/16" or slightly larger.
That is why I asked about the size of the round stock you used to go thru 
the tubing.
Charlie in Canada used 1/2 Cold rolled steel and had the ends (used 2 
pieces) turned down so they slid snuggly in the tubing about 2" and had them 
welded in place. He runs his in graphite bearings mounted on the inside of 
the grill and says it runs true and smooth.
I like the idea of a round rod and bearings but I leave that up to the 
individual. I tried to keep it simple without cutting quality, this helps 
keep the final cost down for the customer.
Cheers
RK

14) From: RK
Thata Boy Dennis jump right in with a full load, I'm impressed, I believe 
about the same as Les as not to get to much heat retention with a diffuser, 
that it will not react quick enough on adjustments.
I know Ed has had great success with the Perforated tiles but I would not 
think that solid tiles or to thick of piece of sheet metal would work as 
well as the perforated tiles or lighter (12 to 14 ga. ( steel) I allow 2" of 
clearance all around for air flow.
Keep up the good work and I wish the best with your roaster.
For that wonder how Dennis did 6lbs in the RK Drum
He bought one of the larger 6lb drums.
Cheers
RK

15) From: Eddie Dove
Dennis,
How and where are you measuring the temperature?
Eddie
On 7/17/07, Dennis & Marjorie True  wrote:
<Snip>

16) From: Dennis & Marjorie True
Thermometer in the hood probe is appx 1 inch from drum.
Thoughts?
Dennis
Eddie Dove wrote:
<Snip>

17) From: Brett Mason
Hi Dennis,
Is the thermometer level with the bean mass?
Is the thermometer shielded from direct flame, so that it will read true?
Regards from the Masons!
Brett
On 7/17/07, Dennis & Marjorie True  wrote:
<Snip>
-- 
Cheers,
Bretthttp://homeroast.freeservers.com

18) From: Dennis & Marjorie True
it is in the hood the probe is just above the half way point of the drum.
the flame is all shielded below with the diffusers that came with the grill
Dennis
Brett Mason wrote:
<Snip>

19) From: Brett Mason
Remember heat rises - so level with the bean mass is best....
Brett
On 7/17/07, Dennis & Marjorie True  wrote:
<Snip>
-- 
Cheers,
Bretthttp://homeroast.freeservers.com

20) From: Eddie Dove
Dennis,
Whatever way you learn to use best for you is the best way.
I have a thermometer in the hood and a thermocouple (that came with my
voltmeter) probe that is centered beneath the rotisserie rod, right at
about bean mass level and about an 1/2 inch from the end of the drum.
I got this from Les and it is working for me.  I have noticed that the
temperature readings between the two can vary as much as 100F.
Hope this helps ...
Eddie
On 7/17/07, Dennis & Marjorie True  wrote:
<Snip>
ll
<Snip>

21) From: Les
So,
Dennis,
How did you cool those 6 pounds of beans?  I remember my first 4 pound
roast!  I softened my vacuum hose so much it just collapsed!  I had to
go to plan B quick and fortunately I had two very clean 5 gallon
buckets to pour back and forth to.  By the way, I have not roasted
with a temp probe for over a year.  When you know where your burners
need to be set at what time, the profiles are repeatable.
Les
On 7/17/07, Eddie Dove  wrote:
<Snip>
m.
<Snip>
rill
<Snip>
ribes) go tohttp://sweetmarias.com/maillistinfo.html#personalsettings<Snip>

22) From: Eddie Dove
Yup, I have found cooling of the larger batches to be challenging,
especially during really hot weather.  I am working on some ideas, but
am very much open to ideas and suggestions.  Please do tell, Dennis!
Another challenge that I found, is that after roasting for several
hours, the propane / propane bottle becomes very could and much less
responsive for heat ramps.  I now have a spare propane bottle at the
ready.
Eddie
-- 
Vita non est vivere sed valere vita est
Roasting Blog and Profiles for the Gene Cafehttp://southcoastcoffeeroaster.blogspot.com/On 7/17/07, Les  wrote:
<Snip>
rum.
<Snip>
 grill
<Snip>

23) From: Homeroaster
I haven't noticed that.  I wonder what the difference might be?  Different 
BTUH propane?
*********************
Ed Needham
"to absurdity and beyond!"http://www.homeroaster.com*********************

24) From: Rich
It is a function of the amount of liquid in the cylinder and the BTU draw from that cylinder.  It takes 
heat to vaporize the propane and that heat is applied mostly to the liquid in the cylinder and not the gas.
On Tue, 17 Jul 2007 23:10:03 -0400, Homeroaster wrote:
<Snip>
<Snip>
<Snip>
<Snip>http://sweetmarias.com/maillistinfo.html#personalsettings

25) From: Les
I would bet that Eddie is stuck using butane, not propane.  Butane
doesn't respond to cold very well compared to propane.  A lot of
butane is sold as propane in the south.
Les
On 7/17/07, Rich  wrote:
<Snip>

26) From: Dennis & Marjorie True
I build a bean cooler
think of a 2X2  foot cube with a box fan both pointing out on the sides 
and a hole cut in the top for a screen trash can with a collender for a 
bottom.
The cooler seems to work pretty well but I still have to move the beans 
around for about a min to get them cool...
Dennis
Les wrote:
<Snip>

27) From: Jerry Procopio
I have been roasting with the RK Drum in a Fiesta (I think it is 45K 
btu) grill for a little over 2 years now.  I roast about 35 - 40 pounds 
a month and usually about 4 batches a month are with 5# of greens in the 
4# drum.  I get good agitation and an even roast and after some trial & 
error have managed to find temperatures to complete the 5# roast in less 
than 24 minutes.
The Fiesta grill came with a corrugated enameled heat diffuser that 
covers most of the bottom of the grill.  I tried covering this with 
other materials (sheet metal, tiles, slate) and never improved my roasts 
so I went back to just the enameled diffuser that came with the grill. 
I get good even (repeatable) roasts, have quick heat up and have control 
of heat throughout the roast.
I'm thinking about adding bearings, but at this point that is about the 
only improvement I would try to make.
JavaJerry
RK Drum roasting in Chesapeake VA
The Dunaways wrote:
<Snip>

28) From: Eddie Dove
This is an excellent thread ...
"I haven't noticed that.  I wonder what the difference might be?
Different BTUH propane?"  - Ed Needham
I dunno.  This past weekend, the tank did "sweat" a lot and become
cool to the touch, but never really slowed down.  I find it more of a
problem with cooler temperatures (<80F) and especially so as the
amount in the tank drops.
"It is a function of the amount of liquid in the cylinder and the BTU
draw from that cylinder.  It takes heat to vaporize the propane and
that heat is applied mostly to the liquid in the cylinder and not the
gas." - Rich
Kinda what I was thinking, but not my bailiwick ...
"I would bet that Eddie is stuck using butane, not propane.  Butane
doesn't respond to cold very well compared to propane.  A lot of
butane is sold as propane in the south."  - Les
I did not know this and this may also be the case.  At one time I had
bottles from different places.  I will pay more attention in the
future.
"think of a 2X2  foot cube with a box fan both pointing out on the sides
and a hole cut in the top for a screen trash can with a collender for a
bottom."  - Dennis
We must have pictures, Dennis!
Thanks to everyone who has contributed to this thread!
Respectfully,
Eddie
-- 
Vita non est vivere sed valere vita est
Roasting Blog and Profiles for the Gene Cafehttp://southcoastcoffeeroaster.blogspot.com/

29) From: Tom Ulmer
Hmmm...
Contrary to popular belief, even down here in the south if they claim it to
be propane it should be. If the claim is that it is LP gas...

30) From: Robert Avery
This is a multi-part message in MIME format.
Just a suggestion .. from my experience with propane or what ever ... a =
lot depends on the surface area of exposure in the tank. The colder it =
gets you need more surface area within the tank. Have you ever notice =
folks that heat their house with propane have the large tank on its side =
and the valve is on the side of the tank ... that's to get more surface =
area to allow adequate surface area of exposure during high volume =
usage. The suggestion is this ... if you are using a standard 20 lb tank =
get two tanks and couple them together. Most of the local propane places =
have these devices and run one line to the grill. I'm sure your problems =
will go away. A larger tank like a 100 lb tank wont give you the surface =
area that two little 20 lb tanks will give you. Believe me ... if you =
are icing up this is the problem, not evaporating fast enough for the =
usage ... take care, Bob

31) From: True, Dennis W. FC1 (CVN69)
I'll post some this evening at Homeroasters of the cooling box and the
grill set up.
I agree this is a good thread and this is helping my learning curve
Tremendously! Thanks again everyone!
Dennis
AKA
V/R,
FC1(SW/AW) Dennis W. True
"Life Liberty and the pursuit of all who threaten it..."
......
We must have pictures, Dennis!
Thanks to everyone who has contributed to this thread!
Respectfully,
Eddie
--

32) From: Justin Marquez
This probably going to be way more than you wanted to know, but here goes.
(Sorry - engineers just can't help themselves sometimes.)
Propane is also a common industrial refrigerant. In your tank, to get more
propane vapor for the burners some of the liquid in the tank must vaporize
to replace the vapor drawn off at the regulator.  This requires that heat to
pass through the cylinder wall and to then vaporize some liquid. As the
liquid boils off, it gets cold (hey - that's what refrigerants do!).  Thus
the tank wall is cooled by the boiling propane next to it. This provides a
temperature difference, thus helping to promote the heat transfer through
the tank wall.
IF your location is cool, then the temperature difference is not as great
and the process can be impeded somewhat. IF your location is very cold (say
-20 Deg F or so) then you can't vaporize any propane without outside heat,
as propane boils at atmospheric pressure at about -20 if memory serves
correctly.
IF your heat requirement is a lot, then the transfer through the wall may
not be able to keep up, particularly if it is cool outside OR if the draw is
actually heavy enough that ice forms on the outside of the tank (unlikely,
but may be possible in cool and humid locations)
The whole sequence goes like this - Your tank is sitting outside and say the
ambient temp is 100 Deg. The tank has an inside pressure of a couple hundred
pounds per sq in. You start the burners at full load. The regulator opens to
satisfy the burner load. The pressure in the tank lowers slightly.  Since
the liquid is at 100 Deg in the tank and you have just lowered the pressure,
propane begins to boil off and the whole vat of propane gets a little
cooler. Now a temperature difference exists between the outside tank wall
and the inside tank wall. Heat flows though to try to establish an
equilibrium condition again. This continues until the lower pressure and
lower temperature inside the tank hit a sweet spot where just enough heat is
coming in through the wall to keep the propane boiling off at a rate exactly
equal to the usage rate. (No entropy was harmed in this experiment.)
To figure how much heat transfer may be required you can start with your
burners' heat rating (say 42,000 BTU/hr), divide that by the BTU's produced
by burning a gallon of propane.  This will give you the gallons/hr  rate to
be vaporized to supply the burners.  Now, multiply that number by the heat
required to vaporize a gallon of propane and the result is the BUT/Hr of
heat transfer through the tank wall to vaporize the propane for the burners
at full rated load.
Safe Journeys and Sweet Music
Justin Marquez (CYPRESS, TX)
On 7/17/07, Eddie Dove  wrote:
<Snip>

33) From: Rich Adams

34) From: Rich
As the liquid level in the tank drops the vaporization =
rate also decreases.  As heat must be added to 
the liquid to vaporize the propane the gas available als=
o decreases.  I am looking for the chart for 20lb 
cylinders.  The gas available vs tank level at a given=
 outside or liquid temperature is what i am looking 
for.  I have it for 100# cylinders but have not loca=
ted one for 20# cylinders.
The fix is to locate the manifold hoses for an RV an=
d hook up 2 20# or 30# cylinders and keep them at =
least half full.  Or, if you have the space and know=
ledge, use a 100# cylinder.  THe 100# cylinder can 
supply 21,000 BTU with a liquid temperature of 40 degree=
s and containing 10# of liquid.  The 20# 
cylinder will be much less with the same conditions.
On Wed, 18 Jul 2007 07:28:56 -0500, Eddie Dove wrote:
<Snip>
<Snip>
might be?
<Snip>
<Snip>
lot and become
<Snip>
find it more of a
<Snip>
o as the
<Snip>
<Snip>
linder and the BTU
<Snip>
he propane and
<Snip>
nder and not the
<Snip>
<Snip>
<Snip>
opane.  Butane
<Snip>
 A lot of
<Snip>
<Snip>
 At one time I had
<Snip>
on in the
<Snip>
<Snip>
inting out on the sides
<Snip>
with a collender for a
<Snip>
<Snip>
<Snip>
<Snip>
<Snip>
cations, unsvbscribes) go to http://sweetmarias.com/maillistinfo.html#personalsettings

35) From: Rich
There are two physical conditions that determine the vaporization rate, along with liquid temperature.  
These are the surface area of the propane liquid and the wetted area.  The solution is either a bigger 
tank or more small tanks.  Or, you can suffer through a 4 year engineering school course of study and 
calculate the exact shortfall of gas available at any time during the roast.  You will need a fully 
instrumented cylinder however.
--Original Message Text---
From: Justin Marquez
Date: Wed, 18 Jul 2007 09:23:10 -0500
This probably going to be way more than you wanted to know, but here goes. (Sorry - engineers just 
can't help themselves sometimes.)
Propane is also a common industrial refrigerant. In your tank, to get more propane vapor for the 
burners some of the liquid in the tank must vaporize to replace the vapor drawn off at the regulator.  
This requires that heat to pass through the cylinder wall and to then vaporize some liquid. As the 
liquid boils off, it gets cold (hey - that's what refrigerants do!).  Thus the tank wall is cooled by the 
boiling propane next to it. This provides a temperature difference, thus helping to promote the heat 
transfer through the tank wall. 
IF your location is cool, then the temperature difference is not as great and the process can be 
impeded somewhat. IF your location is very cold (say -20 Deg F or so) then you can't vaporize any 
propane without outside heat, as propane boils at atmospheric pressure at about -20 if memory serves 
correctly. 
IF your heat requirement is a lot, then the transfer through the wall may not be able to keep up, 
particularly if it is cool outside OR if the draw is actually heavy enough that ice forms on the outside 
of the tank (unlikely, but may be possible in cool and humid locations) 
The whole sequence goes like this - Your tank is sitting outside and say the ambient temp is 100 Deg. 
The tank has an inside pressure of a couple hundred pounds per sq in. You start the burners at full 
load. The regulator opens to satisfy the burner load. The pressure in the tank lowers slightly.  Since 
the liquid is at 100 Deg in the tank and you have just lowered the pressure, propane begins to boil off 
and the whole vat of propane gets a little cooler. Now a temperature difference exists between the 
outside tank wall and the inside tank wall. Heat flows though to try to establish an equilibrium 
condition again. This continues until the lower pressure and lower temperature inside the tank hit a 
sweet spot where just enough heat is coming in through the wall to keep the propane boiling off at a 
rate exactly equal to the usage rate. (No entropy was harmed in this experiment.) 
To figure how much heat transfer may be required you can start with your burners' heat rating (say 
42,000 BTU/hr), divide that by the BTU's produced by burning a gallon of propane.  This will give you 
the gallons/hr  rate to be vaporized to supply the burners.  Now, multiply that number by the heat 
required to vaporize a gallon of propane and the result is the BUT/Hr of heat transfer through the 
tank wall to vaporize the propane for the burners at full rated load. 
Safe Journeys and Sweet Music
Justin Marquez (CYPRESS, TX) 
On 7/17/07, Eddie Dove  wrote: Yup, I have found cooling of the 
larger batches to be challenging,
especially during really hot weather.  I am working on some ideas, but 
am very much open to ideas and suggestions.  Please do tell, Dennis!
Another challenge that I found, is that after roasting for several
hours, the propane / propane bottle becomes very could and much less
responsive for heat ramps.  I now have a spare propane bottle at the
ready.
Eddie

36) From: Edward Rasmussen
Would it be too dangerous to gently use a low power heat gun or hair
drier directed evenly at all areas of the cylinder to raise the internal
temperature when the ambient temperature is too low?
Ed
<Snip>

37) From: Rich
The official answer is that applying external supplemental heat is not allowed.  It will work but it 
takes a lot of BTUs and if there is any gas leak you run the risk of a flash fire.  If you routinely run 
into the low gas delivery problem then the solution is to go to a pair of 100# cylinders.  The double 100
# system is a standard rig that most propane suppliers have.  Your propane dealer is required to 
comply with NFPA 54 and 58.  Not to mention local zoning ordinances.  There are hose type manifold 
rigs that fit neatly on 100# cylinders and can be connected to the grill regulator with a flexible hose.  
If your home is on propane then you can get the fittings and connect the grill into the house system.
Best bet is to talk with the local supplier as they will be conversant with all of the restrictions.
DIY gas plumbing has a high risk factor.
On Wed, 18 Jul 2007 09:30:26 -0600, Edward Rasmussen wrote:
<Snip>
<Snip>
<Snip>http://sweetmarias.com/maillistinfo.html#personalsettings

38) From: Jim Carter
This is a multi-part message in MIME format.
So, putting the propane tank inside the grill is right out then?  :-)
Rich wrote:
<Snip>

39) From: Dennis & Marjorie True
This is a multi-part message in MIME format.
Instant Charbucks!!!!!
Jim Carter wrote:
<Snip>

40) From: Dennis & Marjorie True
Actually I am getting the tank for the house (fireplace) so I will have 
a 250# tank feeding my grill...
MUWHAAAAA!!!!!
Dennis
Rich wrote:
<Snip>

41) From: Justin Marquez
Good point about the reducing area issue as the C3 vaporizes.
We don't need a fully instrumented tank to calculate it, only to prove it.
:-)
Safe Journeys and Sweet Music
Justin Marquez (CYPRESS, TX)
On 7/18/07, Rich  wrote:
<Snip>

42) From: Dennis & Marjorie True
Ok Eddie and anyone interestedhttp://www.homeroasters.org/php/forum/viewthread.php?forum_id6&thread_idU6here is the link to the pics you requested for the RK set up and the cooler
if there are any questions let me know!
Dennis
<Snip>

43) From: Robert Avery
This is a multi-part message in MIME format.
I myself wouldn't go there .... you don't need to compromise your =
safety. A side from that .... I don't think you could pour enough heat =
to the tank with a hot air gun. For the liquid to turn to a gas it has =
to pull heat from someplace. Of course the faster the usage the more =
evaporation that is needed which puts you into a race for supplying =
enough heat to change the liquid to a gas. Hence .. the reason for the =
frost forming on the tank. Sitting in the sun will help or a warm place =
.. but I really wouldn't push the envelope of invention, if you know =
what I mean. Later, Bob

44) From: Rich
I have placed the 20# cylinder in front of a torpedo heater and it does not keep the cylinder hot 
enough.  It was a very high output heater by the way, 325,000 BTU.  I use a 500 gal tank out doors and 
it keeps up with the big heater.
--Original Message Text---
From: Jim Carter
Date: Wed, 18 Jul 2007 12:33:46 -0400
So, putting the propane tank inside the grill is right out then? :-) 
Rich wrote: The official answer is that applying external supplemental heat is not 
allowed. It will work but it 
takes a lot of BTUs and if there is any gas leak you run the risk of a flash fire. If 
you routinely run 
into the low gas delivery problem then the solution is to go to a pair of 100# 
cylinders. The double 100
# system is a standard rig that most propane suppliers have. Your propane dealer is 
required to 
comply with NFPA 54 and 58. Not to mention local zoning ordinances. There are hose 
type manifold 
rigs that fit neatly on 100# cylinders and can be connected to the grill regulator 
with a flexible hose. 
If your home is on propane then you can get the fittings and connect the grill into 
the house system.
Best bet is to talk with the local supplier as they will be conversant with all of 
the restrictions.
DIY gas plumbing has a high risk factor.
On Wed, 18 Jul 2007 09:30:26 -0600, Edward Rasmussen wrote:
Would it be too dangerous to gently use a low power heat gun or hair
drier directed evenly at all areas of the cylinder to raise the internal
temperature when the ambient temperature is too low?
Ed

45) From: Rich
I am getting a picturre of the commercial wherre the grill blows up and the wife does not notice....
--Original Message Text---
From: Dennis & Marjorie True
Date: Wed, 18 Jul 2007 12:52:17 -0400
Instant Charbucks!!!!!
Jim Carter wrote: So, putting the propane tank inside the grill is right out then? :-) 
Rich wrote: The official answer is that applying external supplemental heat is not 
allowed. It will work but it 
takes a lot of BTUs and if there is any gas leak you run the risk of a flash fire. If 
you routinely run 
into the low gas delivery problem then the solution is to go to a pair of 100# 
cylinders. The double 100
# system is a standard rig that most propane suppliers have. Your propane dealer is 
required to 
comply with NFPA 54 and 58. Not to mention local zoning ordinances. There are hose 
type manifold 
rigs that fit neatly on 100# cylinders and can be connected to the grill regulator 
with a flexible hose. 
If your home is on propane then you can get the fittings and connect the grill into 
the house system.
Best bet is to talk with the local supplier as they will be conversant with all of 
the restrictions.
DIY gas plumbing has a high risk factor.
On Wed, 18 Jul 2007 09:30:26 -0600, Edward Rasmussen wrote:
Would it be too dangerous to gently use a low power heat gun or hair
drier directed evenly at all areas of the cylinder to raise the internal
temperature when the ambient temperature is too low?
Ed

46) From: Oaxaca Charly
RK  wrote: Rich are you sure you used a 1/2" shaft to drive thru the hollow tubing?. I 
know that the laser burned holes in the end plate are .515 which gives the 
1/2 OD hollow tubing enough space to slide thru the end plates and then tig 
welded in place. The inside of the hollow tubing varies in size but 
generally should be near 7/16" or slightly larger.
That is why I asked about the size of the round stock you used to go thru 
the tubing.
Charlie in Canada used 1/2 Cold rolled steel and had the ends (used 2 
pieces) turned down so they slid snuggly in the tubing about 2" and had them 
welded in place. He runs his in graphite bearings mounted on the inside of 
the grill and says it runs true and smooth.
  I had to have my 1/2" SS solid rod, (not a hollow tube) lathed a little to fit *very* snug into the ends, no welding needed. What was important was to have the rods set so that they come exactly straight from the end pieces. One is a tiny, tiny fraction off true so the drum has a slight wobble and the beans are thrown just a little more to one end than the other , which causes the drum unit to keep moving away from the motor end connector. It's the one and only problem I have using my RK since replacing the cheapo rotisserie rod and making grafite saddles for the ss rod to spin on. And replacing the lid pin with a paper clip (big improvement!) My graphite "saddles' sit just outside the grill. They could go inside, they sure won't melt, but my extra large RK drum doesn't leave much room in there. They're in open topped steel boxes bolted to the grill. No squealing, ever--what a relief that is.
Charly
I
---------------------------------
Need a vacation? Get great deals to amazing places on Yahoo! Travel. 

47) From: raymanowen
Propane and Butane are similar enough that they can be mixed together.
Liquid Butane vaporizes at a much higher temperature than Propane. When the
ambient temperature is below freezing, the vaporization of Butane is
retarded- that might be why they send it south where they got more degrees.
Just think, Vicki and many Canucks can't use Butane most of the year, so why
waste Propane in climes where its low bp isn't necessary?
Cheers -RayO, aka Opa!
"All progress has resulted from people who took unpopular positions."  -
-Adlai Stevenson
**

48) From: stereoplegic
dude! sweet setup! one suggestion: add a gearhead (ie low rpm, high 
torque) motor at the bottom of the colander w/ stirring arms on its 
shaft. it'll do the stirring for you, not to mention helping w/ chaff 
removal. posted this same reply on homeroasters.org so others can see.
dmtrue wrote:
<Snip>

49) From: Vicki Smith
Yup, and in fact, folks around here spend the extra $$ and plumb in a 
natural gas BBQ so we can stand like idiots in a snow bank when we want 
a steak.
v
raymanowen wrote:
<Snip>


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