HomeRoast Digest


Topic: Cracking Continuously (31 msgs / 856 lines)
1) From: Ronnie Kramer
I've been roasting for all of 5 days now and trying to figure out what a crack sounds like.  I swear I heard it during my last two roasts.  It sounds like corn popping, but lower and muffled with all the other noise going on.  The sound starts definitively, that is it's not cracking then it is.  Not just one or two pops at first.
   
  Thing is, it doesn't stop until I hit cool.  I've taken these roasts to Vienna/light french.  Is it possible there is no pause between first and second crack?  Or should I be listening for something else?
   
  -Ronnie
Ronnie Kramer
Austin, TX

2) From: Edward Bourgeois
Ronnie   What you described sounds like first crack.  2nd sounds more like
rice krispies

3) From: Brett Mason
Can you tell us what roaster you are using?
On 1/16/07, Ronnie Kramer  wrote:
<Snip>
-- 
Cheers,
Bretthttp://homeroast.freeservers.com

4) From: Peter Zulkowski
Ronnie,
What I have noticed is that there is a lot of smoke just before first crack.
Again before second.
Hope this helps,
PeterZ
Ronnie Kramer wrote:
<Snip>

5) From: Ronnie Kramer
I'm using an I-roast 2.  Maybe my ear just hasn't learned to discern between the sound of first and second crack.  But I'm getting to vienna without the cracking (I think) ever stopping.  It started about 4 minutes into the last roast.  When the beans were beginning to brown and mottle, just before I noticed them expanding a little.  About six minutes later I hit cool.  The beans were about vienna colored and shiney all over.  The sound never let up.  Though I did notice it speed up for about 15 seconds, two minutes before I ended the roast.
Brett Mason  wrote:  Can you tell us what roaster you are using?
  On 1/16/07, Ronnie Kramer  wrote:     I've been roasting for all of 5 days now and trying to figure out what a crack sounds like.  I swear I heard it during my last two roasts.  It sounds like corn popping, but lower and muffled with all the other noise going on.  The sound starts definitively, that is it's not cracking then it is.  Not just one or two pops at first. 
   
  Thing is, it doesn't stop until I hit cool.  I've taken these roasts to Vienna/light french.  Is it possible there is no pause between first and second crack?  Or should I be listening for something else? 
   
  -Ronnie
Ronnie Kramer
Austin, TX 
-- 
Cheers,
Bretthttp://homeroast.freeservers.com
Ronnie Kramer
Austin, TX

6) From: Ronnie Kramer
Well,
   
  I've been using a vent pipe and can't really see the smoke and watch the roast at the same time.  Otherwise my smoke detectors go crazy.  Next time I'll remove the batteries and try without the vent.
Peter Zulkowski  wrote:
  Ronnie,
What I have noticed is that there is a lot of smoke just before first crack.
Again before second.
Hope this helps,
PeterZ
Ronnie Kramer wrote:
<Snip>Ronnie Kramer
Austin, TX

7) From: miKe mcKoffee
Peter, are you sure. My experience tends to see little smoke going into and
well into 1st. Smoke starting to build one of the signs of approaching 2nd.
Of course, depends on the speed of the roast whether smoke is approaching
2nd or crashing into 2nd! Cracks starting 4min into the roast (regardless
whether 1st or 2nd) indicates a pretty fast roast IMO. Sounds to me like 1s5
and 2nd running together, also from too fast a roast. Dark brown and shiny
definitely indicative of well into 2nd crack. FWIW reducing weight of greens
one method of slowing an air roast.
Kona Konnaisseur miKe mcKoffee
URL to Rosto mods, FrankenFormer, some recipes etc:http://mdmint.home.comcast.net/coffee/Rosto_mod.htmUltimately the quest for Koffee Nirvana is a solitary path. To know I must
first not know. And in knowing know I know not. Each Personal enlightenment
found exploring the many divergent foot steps of Those who have gone before.
<Snip>
<Snip>
[mailto:homeroast-admin] On Behalf Of Ronnie Kramer
	Sent: Tuesday, January 16, 2007 4:48 PM
	
<Snip>
	I'm using an I-roast 2.  Maybe my ear just hasn't learned to discern
between the sound of first and second crack.  But I'm getting to vienna
without the cracking (I think) ever stopping.  It started about 4 minutes
into the last roast.  When the beans were beginning to brown and mottle,
just before I noticed them expanding a little.  About six minutes later I
hit cool.  The beans were about vienna colored and shiney all over.  The
sound never let up.  Though I did notice it speed up for about 15 seconds,
two minutes before I ended the roast.

8) From: Bob
This is a multi-part message in MIME format.
Ronnie,
I agree w/MiKe--cracks running together. Own both I-Roasts and the trick =
is to prolong the roast as much as this piece of equipment will allow. =
IMO hooking it into a venting system is very much at odds w/ this goal.
Suggest you peruse the archives--much has been discussed about the =
I-Roasts, their limitations, and mods to make it perform better.
Good luck, VegasBob
MiKe--are you de-cloaked for a while?--hope so. Miss ya.
  Austin, TX

9) From: Ronnie Kramer
So if first and second are running into each other, would reducing the profile temps slow it down?  Or should I just reduce amount of beans?  I've been using the profile from Sweet Maria's tip sheet.  The one Tom says he uses for most all of his cupping for City to City + roasts.
   
  Stage I     2:00 @ 350 F
  Stage II    3:00 @ 400 F
  Stage III   4:30 @ 460  F
   
  At about 7:30 into the roast I get a City or City+.  At about 8:30 I get a City+ to FC.
   
  When going the full 9:30, I've gotton FC+ with Colombia Tolima Planadas, and Vienna/Light French with Nicaragua Limoncillo Estate, which is a bigger bean and has less chaff.
   
  All roasts were with 150g green and around 68F ambient.
   
  I hope this will help you help me.
   
  -Ronnie
  
miKe mcKoffee  wrote:
  Peter, are you sure. My experience tends to see little smoke going into and
well into 1st. Smoke starting to build one of the signs of approaching 2nd.
Of course, depends on the speed of the roast whether smoke is approaching
2nd or crashing into 2nd! Cracks starting 4min into the roast (regardless
whether 1st or 2nd) indicates a pretty fast roast IMO. Sounds to me like 1s5
and 2nd running together, also from too fast a roast. Dark brown and shiny
definitely indicative of well into 2nd crack. FWIW reducing weight of greens
one method of slowing an air roast.
Kona Konnaisseur miKe mcKoffee
URL to Rosto mods, FrankenFormer, some recipes etc:http://mdmint.home.comcast.net/coffee/Rosto_mod.htmUltimately the quest for Koffee Nirvana is a solitary path. To know I must
first not know. And in knowing know I know not. Each Personal enlightenment
found exploring the many divergent foot steps of Those who have gone before.
<Snip>
<Snip>
[mailto:homeroast-admin] On Behalf Of Ronnie Kramer
Sent: Tuesday, January 16, 2007 4:48 PM
<Snip>
I'm using an I-roast 2. Maybe my ear just hasn't learned to discern
between the sound of first and second crack. But I'm getting to vienna
without the cracking (I think) ever stopping. It started about 4 minutes
into the last roast. When the beans were beginning to brown and mottle,
just before I noticed them expanding a little. About six minutes later I
hit cool. The beans were about vienna colored and shiney all over. The
sound never let up. Though I did notice it speed up for about 15 seconds,
two minutes before I ended the roast.Ronnie Kramer
Austin, TX

10) From: Vicki Smith
H Ronnie, when I first got my IR2, I thought that I was hearing a 1st 
crack that went on and on, but what I really was hearing was the bean 
movement.
In my experience, you can hear first easier if you are roasting in a 
room without much in the way of sound absorbing shtuff around it--a hard 
surface behind it. That's why I hear the cracks far better if I am 
roasting in my cement garage, than in my kitchen. It also helps if you 
step back from the roaster a bit, so that the 1st crack sounds ring out 
over the sound of the bean movement.
2nd crack is harder to hear. Sometimes I just don't, so I rely on smells 
and smoke for guidance.
vicki
Ronnie Kramer wrote:
<Snip>

11) From: Vicki Smith
I have mine vented, but I can still see the smoke as it goes out the 
vent and into the air outside of the window. Perhaps you need to roast 
someplace where it is venting at eye level.
v
Ronnie Kramer wrote:
<Snip>

12) From: Alchemist John
Mike, I would say the difference in your experience and Peter's is 
the amount roasted.  At a pound (which I tend to recall Peter doing) 
there is quite the amount of smoke before 1 st and then more at 
2nd.  In the Rosto and other "smaller" ounce roasters, I recall there 
is little to no smoke at 1 st.  Now, 5 lbs - wow, there is smoke! at 1st.
Ronnie, running of 1st and 2nd crack is pretty common of a profile 
that is too fast.  Try cutting your heat profile back, possible 
before 1st.  Often the momentum hitting 1st is enough to just carry 
it straight through to 2nd.
At 17:08 1/16/2007, you wrote:
<Snip>
John Nanci
AlChemist at large
Zen Roasting , Blending & Espresso pulling by Gestalthttp://www.chocolatealchemy.com/

13) From: Phil Bergman
Ronnie,
My first post here.  I'm new to roasting and using a IR2 as well.  I've done
about 30 roasts and have learned to hear the first crack (thanks to a lot of
guidance by others' comments).  To me, it sounds like a light but sharp tap
on the glass wall of the roasting compartment.  More of these follow.
Second crack is a lot harder for me to hear but is audible, and is more like
someone called it, "rice crispies in milk".  I can't see smoke as I use a
metal duct elbow to an exit vent to the outside.  But, I definitely watch
the color.  I'm having fun so far and definitely realize I'm a novice with a
lot to learn.  I'd say 33% of my roasts so far have been great, 33% OK, and
33% not good at all.  I hope the numbers improve with time and knowledge.
Best regards,
Phil B.

14) From: Ronnie Kramer
Thanks for all the suggestions everyone,
   
  Vickie mentioned at one point she thought she was hearing a first crack that just went on and on, but it turned out to be bean movement.  I can hear the beans hitting the glass as they fall back down.  Then I thought maybe it's the beans in the mass sliding along the bottom of the chamber making the sound I hear.  But there is a distinct 'start' to the sound after about 4 minutes.  This doesn't rule out bean movement given the change to the bean texture, moisture, mass and size.  But it makes me second guess.
   
  Next time I'll try lowering my temperature profile as suggested by someone.  Also lower my vent so I can see it through the window as Vickie suggested.  As far as where I roast, I don't have many options to relocate at this time, unless I want to stand in the snow:)
   
  Many Thanks!
  -Ronnie
Ronnie Kramer  wrote:
    I've been roasting for all of 5 days now and trying to figure out what a crack sounds like.  I swear I heard it during my last two roasts.  It sounds like corn popping, but lower and muffled with all the other noise going on.  The sound starts definitively, that is it's not cracking then it is.  Not just one or two pops at first.
   
  Thing is, it doesn't stop until I hit cool.  I've taken these roasts to Vienna/light french.  Is it possible there is no pause between first and second crack?  Or should I be listening for something else?
   
  -Ronnie
Ronnie Kramer
Austin, TX
Ronnie Kramer
Austin, TX

15) From: Vicki Smith
I'm betting it isn't first crack at four minutes, unless your particular 
IR2 runs really hot and fast. As the beans expand, the sound of the 
beans in the chamber changes--really. That is the sound I thought was 
1st crack.
v
Ronnie Kramer wrote:
<Snip>

16) From: Paul Martin
John,
Thanks for the explanation of size and smoke.  I'm just starting out in my
hot air popper and I've seen no smoke.  It does become a little "fragrant"
but no smoke.
Paul

17) From: Alchemist John
I recalled this from Ed Needham, and then experienced it first 
hand.  If I do a "small" batch of 10 oz, there is fragrance and 
little smoke, but 22 oz really has it pouring out pre-first.  Also, 
air poppers keep it dissipated where as non-forced air drum roasts, 
well, don't :P
At 20:05 1/16/2007, you wrote:
<Snip>
John Nanci
AlChemist at large
Zen Roasting , Blending & Espresso pulling by Gestalthttp://www.chocolatealchemy.com/

18) From: miKe mcKoffee
Good point Alchemist. It's over a year since I've played with larger than
1/2# batches. But now that you mention it seem to recall 1# wok batches did
seem to emit noticeable smoke earlier. I sit corrected.
Kona Konnaisseur miKe mcKoffee
URL to Rosto mods, FrankenFormer, some recipes etc:http://mdmint.home.comcast.net/coffee/Rosto_mod.htmUltimately the quest for Koffee Nirvana is a solitary path. To know I must
first not know. And in knowing know I know not. Each Personal enlightenment
found exploring the many divergent foot steps of Those who have gone before.
<Snip>

19) From: raymanowen
Ronnie,
Exactly what is your vent like? If you have a direct-connected vent pipe
that depends on the roaster's blower to move all the air through the I Roast
and the vent pipe, the vent is a bottleneck.
   - Right angle bends in the pipe are your enemy.
The plumbing in your house has lots of right angle bends, but the water
pressure is much higher.
In the drain pipes where there is no real pressure, there are curves but no
sharp corners.
   - Any of the corrugated flexible pipe in your system totally disrupts
   the gas flow through it. The stuff ought to be banned. My clothes dryer runs
   far better with solid sheet metal ducts than the white vinyl flex for the
   exhaust duct.
You might try to rig up a fume hood or roasting box with some 4" PVC drain/
waste/ vent pipe and a muffin fan.
Cheers -RayO, aka Opa!
Only advanced novices start roasting with an I Roast.

20) From: Aaron
ronnie, I use the I roast 1 and I have noticed that on some batches, 
yes, first will run right into second.  You won't get a big crack fest, 
slowdown, then the lighter sounding cracks of second, but it will just 
start cracking, and steadily roll along until you hit the cool button.
Given the whole process is over in what,  generally 8 minutes tops for a 
really dark roast, everything is kind of happening a bit faster so at 
times there won't be any 'time' i guess you could say... for a breather 
between the cracks.
Your best bet here is to use smell, and watch the bean color to tell 
when they are done to your liking.
aaron

21) From: Aaron
Prolonging the roast will help a bit, but some types of beans, you are 
just going to run the cracks together.  I have roasted probably a few 
hundred roasts in my I roast, and some have a definate first and second, 
and others, they just kind of run together with no starting or stopping 
point.
You might want to try to reduce the amount of greens you have,  go from 
6 ounces to say 5.5 or 5 ounces of greens in there.  This will allow a 
bit more air movement, and bring the temp down a bit in the heat pit, 
and should help slow the process down a bit.
I use a general formula for pretty much all my I roast roasting.
375F  for 3 min  if it's cool in the room goto 380.
400F  for 3 min  if it's cool in the room goto 405.
425F  for  whatever it takes to get to where you like them.  since i 
dont like really dark roasted coffee's I tend to run this for 1.5 to 2 
minutes. then hit the cool.
what happens for me is generally between 5,30 to 5.45 into the roast, 
first crack will start happening, then when it hits the final heat boost 
at the 600 minute mark first really takes off.   I let it run until 
first pretty much stops, and there's a pause for about 30 seconds,  or 
until second just starts, or the beans are turning as dark as I wanted 
them.  My entire roast generally is over at 730 to 745 ish mark.... i 
hit the cool and go from there.
If you are going to play around, id recommend making one change at a 
time,  ie try the bean weight first, then change the temps etc etc. that 
way you know exactly what did what and have a bit more control over the 
outcome.
Aaron

22) From: Ronnie Kramer
You may be right.  I'll figure it out one day, soon I hope.  But I can't roast anymore at least for 2 or 3 days.  In the last 5 days I've roasted 2 2/3 lb of green.  Of course, half of that has passed through my teeth.  I'd like to roast more today.  With the holiday on Monday, and my company closed due to weather yesterday, AND today for weather, and I hadn't planned or prepared for a 5 day weekend, I sure hope I can resist roasting just one more batch.  Otherwise I have no idea what I'm going to do all day, and it's only 6:20 am now.
   
  Guess I'll be sipping:)
Vicki Smith  wrote:
  I'm betting it isn't first crack at four minutes, unless your particular 
IR2 runs really hot and fast. As the beans expand, the sound of the 
beans in the chamber changes--really. That is the sound I thought was 
1st crack.
v
Ronnie Kramer wrote:
<Snip>Ronnie Kramer
Austin, TX

23) From: Ronnie Kramer
Ray,
   
  I'm using a direct connected flexible vent.  But it's not the flimsy springy type.  It's fairly ridgid.  There are curves in it, but not right angles.
   
  I'll consider setting up some sort of hood to get rid of the direct connect.  Actually, a roasting box sounds like fun.
   
  Thanks Ray, that info is good to know.
   
  -Ronnie
raymanowen wrote:
  Ronnie, 
Exactly what is your vent like? If you have a direct-connected vent pipe that depends on the roaster's blower to move all the air through the I Roast and the vent pipe, the vent is a bottleneck.
   Right angle bends in the pipe are your enemy.
The plumbing in your house has lots of right angle bends, but the water pressure is much higher. 
In the drain pipes where there is no real pressure, there are curves but no sharp corners. 
    
   Any of the corrugated flexible pipe in your system totally disrupts the gas flow through it. The stuff ought to be banned. My clothes dryer runs far better with solid sheet metal ducts than the white vinyl flex for the exhaust duct. 
You might try to rig up a fume hood or roasting box with some 4" PVC drain/ waste/ vent pipe and a muffin fan.
Cheers -RayO, aka Opa!
Only advanced novices start roasting with an I Roast.
Ronnie Kramer
Austin, TX

24) From: Ronnie Kramer
Thanks Aaron,
   
  I've been getting good to excellent results in the cup using my eyes and watching the bean color and texture.  I just sooo want to know that I'm hearing the cracks.
Aaron  wrote:
  ronnie, I use the I roast 1 and I have noticed that on some batches, 
yes, first will run right into second. You won't get a big crack fest, 
slowdown, then the lighter sounding cracks of second, but it will just 
start cracking, and steadily roll along until you hit the cool button.
Given the whole process is over in what, generally 8 minutes tops for a 
really dark roast, everything is kind of happening a bit faster so at 
times there won't be any 'time' i guess you could say... for a breather 
between the cracks.
Your best bet here is to use smell, and watch the bean color to tell 
when they are done to your liking.
aaronRonnie Kramer
Austin, TX

25) From: Ronnie Kramer
I'm going to have to change something.  I'll try one thing at a time.  First I'll adjust the temp profile.  I just hate changing the amount of beans.  150g X 3 = 1lb.  It's just too cool that my IR2 roasts one pound of green in exactly 3 batches:)
   
  As long as the cup tastes good, I'm resisting changing the amount of beans!
   
  -Ronnie
Aaron  wrote:
  Prolonging the roast will help a bit, but some types of beans, you are 
just going to run the cracks together. I have roasted probably a few 
hundred roasts in my I roast, and some have a definate first and second, 
and others, they just kind of run together with no starting or stopping 
point.
You might want to try to reduce the amount of greens you have, go from 
6 ounces to say 5.5 or 5 ounces of greens in there. This will allow a 
bit more air movement, and bring the temp down a bit in the heat pit, 
and should help slow the process down a bit.
I use a general formula for pretty much all my I roast roasting.
375F for 3 min if it's cool in the room goto 380.
400F for 3 min if it's cool in the room goto 405.
425F for whatever it takes to get to where you like them. since i 
dont like really dark roasted coffee's I tend to run this for 1.5 to 2 
minutes. then hit the cool.
what happens for me is generally between 5,30 to 5.45 into the roast, 
first crack will start happening, then when it hits the final heat boost 
at the 600 minute mark first really takes off. I let it run until 
first pretty much stops, and there's a pause for about 30 seconds, or 
until second just starts, or the beans are turning as dark as I wanted 
them. My entire roast generally is over at 730 to 745 ish mark.... i 
hit the cool and go from there.
If you are going to play around, id recommend making one change at a 
time, ie try the bean weight first, then change the temps etc etc. that 
way you know exactly what did what and have a bit more control over the 
outcome.
AaronRonnie Kramer
Austin, TX

26) From: Ken Mary
<Snip>
I have never used an IRoast. Have you tried longer (slower) profiles to the
maximum time available? Do you prefer the taste of the faster profiles? I
spent 5 years with different style poppers and never ran first into second
unless the total roast time was under 4 minutes. BTW, I did prefer those
very fast roasts over the slower profiles.
If the internal temperature sensor is slow to respond, you may be
overshooting your desired temperature. I suggest that you reduce the 3rd
stage setting so that the maximum time expires at the appropriate roast
level. First should begin soon after the 3rd stage begins. If it does not
then raise the 2nd stage. You may be correct in allowing first to begin late
in the second stage. But if so then your 3rd stage needs to be set much
lower. After first, the beans need very little more heat to proceed into
second.
--

27) From: Ronnie Kramer
OK,
   
  I've been looking at my notes, for whatever that's worth.  Going by words like browning a little more, mottled, wrinkly, and the occasional "was that the crack,"  I'm fairly confident that first crack is beginning between 5:00 and 6:00, which is just at the beginning to 1:00 into Stage III.
   
  Stage I    2:00 @ 350F
  Stage II   3:00 @ 400F
  Stage III  4:30 @ 460F
   
  I've gotton barely City @ 7:15 (0:45 after 1C starts); City + around 7:30 to 8:00 (about 1:30 af ter 1C starts); FC/FC+ around 9:30 to 10:30 (about 4:00 to 5:30 after 1C starts, FC+ defined as first drops of oil on bean); and vienna to light french (defined as shiney) around 9:30 to 10:30 (about 3:30 to 5:30 after 1C starts).
   
  Once the chaff collector was not on properly and I unplugged the IR2 at 1:30 and restarted immediately.  I heard the 'cracking' at a total of 5:00 (about like the others), but in this case it was still in Stage II, so I know Stage II can get me to first crack if extend the time.
   
  It seems that just as, or just before 1C, I'm ramping up the temp (Stage III) from 400F to 460F.
   
  I think I should extend Stage I, and Stage II by one minute each to ensure 1C starts in Stage II.  And reduce the temp of Stage III from 460F to 425F and extend it the the full 15:00 limit.  This would give me;
   
  Stage I    3:00 @ 350F
  Stage II   4:00 @ 400F
  Stage III  8:00 @ 425F
   
  Of course, the goal here is not to get a better cup of coffee.  I'm just wanting to learn and understand if I'm really hearing the cracks by seeing if I can seperate 1C and 2C.  After I find what I'm looking for I may well go back to the original profile if the cup is better:)
   
  I can probably resist doing another roast until early afternoon if anyone has any comments/recommendations on the above paln.
   
Ronnie Kramer  wrote:
    I've been roasting for all of 5 days now and trying to figure out what a crack sounds like.  I swear I heard it during my last two roasts.  It sounds like corn popping, but lower and muffled with all the other noise going on.  The sound starts definitively, that is it's not cracking then it is.  Not just one or two pops at first.
   
  Thing is, it doesn't stop until I hit cool.  I've taken these roasts to Vienna/light french.  Is it possible there is no pause between first and second crack?  Or should I be listening for something else?
   
  -Ronnie
Ronnie Kramer
Austin, TX
Ronnie Kramer
Austin, TX

28) From: Phil Bergman
This is a multi-part message in MIME format.
Ray,
I was the one who mentioned a right angle metal elbow.  It fits perfectly
over the metal cage on the IR2.  It is the same diameter.  It goes up about
5 inches and then elbows.  I put the end of the elbow in front of a exhaust
fan in the wall of the kitchen.  Literally no smoke escapes into the
kitchen.  I've wondered if the draw of the exhaust fan would affect
temperatures of the IR2, but haven't seen that for sure.  I can still get
into the 400's.  If I walk outside during the roast, all the smoke and
smells are outside the kitchen.
Phil

29) From: Aaron
Ron in that case the amount of beans is pretty good, as it is about oh  
5.33 oz per batch, a good place.  They say you can do up to 6 ounces in 
the I roast but many beans, the expansion they start filling up too much 
of the cooking bowl and don't move around as much as they should and it 
can be problematic and you end up doing the swirl routine or lifting the 
cap to increase air circulation because the beans are not really moving 
anymore in it......  Your bean amount should work just fine.
one note though, peaberries, I have had the most problems with when it 
comes to movement in the roaster.. some of them expand an enormous 
amount from what you start out with and dont want to move well in the 
chamber.. so IF you were thinking of pushing the bean limit on a roast, 
peaberry is not the one to do it on....  just my.02
Good luck and let us know how it turns out for you.
also, if the beans are getting done too fast, you can always hit the 
cool button to stop the cooking before the timer runs out and if they 
progressing too slowly you can always add time.
Aaron

30) From: Aaron
Ken that's exactly what I have been doing pretty much ...kind of.
The beans are right at the threshold of first crack at the end of the 
second stage, with a few snaps here and there, but once third stage 
kicks in, the temp goes up the beans hit first crack and go well from 
there.  In other words, third stage is where the threshold is exceeded 
for the crack temp.  Now i am sure if I left the beans at the same temp 
for another few minutes in second stage theyd eventually get into first 
crack but i find that I like the results better, bringing them there, 
holding them at the brink then giving them the push over for the final 
minute or so of good solid crack.
One thing I do have to note though.  This is MY I ROAST NOT YOURS!!!!
Each I roast is going to be it's own beast with a different behavior 
pattern.  What works in one, might be different in another.  I have 3 I 
roasts I use regularly and each has it's little quirks. The temp 
readouts are different on all of them... another lets more air through 
the top so I need it hotter.. etc etc... one will have to find the 
'sweet spot' for their specific unit.
 Another thing I noticed with the I roasts, theres seems to be a brief 
period where they were using fan speed to control the heat instead of 
heater temp as the main control and there seems to be two 'operating 
methods' to the I roasts.
Method one.. the unit kicks on, keeps at a steady fan speed, slows it 
down slightly as you progress through stages and dial in for a hotter 
temp, ONLY ramping up fan speed if the beans stall or temp gets too high 
in the bottom cook area.
Method two... the thing pretty much oscilloates high / lower speed 
through the entire cooking cycle... annoying as hell and I find the 
results of this are a more uneven roast unless you are taking it pretty 
dark.  It seems they noticed this was not a good thing either as the 
later models reverted back to the constant speed mode.... im assuming 
later models by looking at the serial #'s of the units I have, and again 
would assume they manufactured them with the SN's pretty much in 
numerical order so that, oh say  unit 1million was probably made before 
unit sn 2.5 million etc etc.  Also, I do not know if this is related or 
not but I have found that this method, these units are more prone to 
being louder, vibrating much more and subject to bearing/bushing  
failure sooner than the constant speed models.
If I roast wants to send me about 4 or 5 of each to thoroughly test Id 
be happy to report the results to them :)
Ok im rambling here,  hope this helps.
Aaron

31) From: Carole Zatz
Hi Ronnie,
I've had two different iRoast2s and they required very different
profiles to get similar results. It sounds like you're definitely
getting closer to very useable one. For my first iRoast2 (which ran
fairly hot) the profile I had the best results from (longest and
steadiest roasting times) was:
Stage I   2:00 @ 320F
Stage II  2:00 @ 350F
Stage III 2:00 @ 375F
Stage IV 2:00 @ 400F
Stage V  7:00 @ 425F
With this profile I typically hit first crack at around 7 minutes into
the roast and then hit cool at whatever degree of roast that I wanted
for that bean (anywhere from 10 to 11 minutes into the roast).
When I tried this profile with my new iRoast2, everything burned. The
new machine ran even hotter. The roast would hit first crack at about
the same time but then immediately go into second. So it was back to
the drawing board. The profile I finally worked out to give me a
gradual ramp-up and then extend the time between the first crack and
the second is quite different than the earlier one:
Stage I   4:30 @ 385F
Stage II  2:00 @ 420F
Stage III 1:00 @ 405F
Stage IV 3:00 @ 345F
Stage V  4:30 @ 400F
As you can see, I had to greatly reduce the temperature after hitting
first crack at around 6 minutes into the roast. It then gives me some
breathing room before second crack starts (usually around 9 minutes
into the roast). I still am not getting quite the same results as
earlier, but it is better. I still need to slow it down even more.
So don't be afraid to reduce temperatures if you find it's necessary.
Also, the bean variety really makes a big difference. For example,
when I roast PNG or Yemin, I cool at around 12 minutes and it's still
not into Full City. But when I did a Sumatra Blue Lintong it hit Full
City+ at 9 minutes. The drop in fan speed that happens at the start of
Stage II pushes it into first crack and then the drop in temperature
keeps the roast going until it after 2 1/2 to 5 minutes it eventually
goes into second crack. I'd like to gain a couple of minutes before
first crack and then a couple more before second ....
So I'm still fine-tuning as well  its been about a month now with the ne=
w one!
Ronnie Kramer  wrote:
I think I should extend Stage I, and Stage II by one minute each to
ensure 1C starts in Stage II.  And reduce the temp of Stage III from
460F to 425F and extend it the the full 15:00 limit.  This would give
me;
 Stage I    3:00 @ 350F
 Stage II   4:00 @ 400F
 Stage III  8:00 @ 425F


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