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B-2K+ 1st crack way too early
lparsons21
Just got a B-2K+ yesterday. I've done 2 roasts so far, one a Colombian the other a Honduran bean. In both cases 1st crack started at about 335 degrees F indicated BT. Documentation indicates that I should get to 365 degrees and the indicator to turn brown indicating 1st crack is imminent. It does turn brown at 365 degrees, but 1st crack has just finished by then.

2nd crack starts @390 degrees F for info.

In both cases the roast profile is 100% heat, no fan until 1st crack starts.

Seems early though both roasts turned out quite good. Is this normal? I suppose if it is consistently about 30 degrees low then it isn't a big issue, just seems odd. But with that difference it would seem that if I ever let it get to 408 degrees I would be in deep fire mode!
Lloyd
 
woodchuck
Temperature probes do vary quite a bit from roaster to roaster. Then main thing is that they are consistent from roast to roast. Also make sure you have a full charge. Light loads generally are more unreliable from a metering point of view.
Roasters: TJ-067, Hottop with TC4C and RAF Mods
Espresso: LaSpaziale VII/Macap M4 Grinder
Pour over: Bonmac Pro Cone
Press: Bodum
 
lparsons21
Thanks. The two roasts I have done were both 9 oz. which is the weight given in the documentation.

I probably won't get another roast in for about a week as it takes me time to go through what I have done so far.
Lloyd
 
lparsons21
After doing some more reading here, I'm thinking maybe not run 100% heat and no fan until start of 1st crack might change things a bit. Thinking that it may be a lag in the probes/computer inside this baby.

I guess I need to find someone to give some coffee to since it looks like I'll be roasting a bit more sooner than I though!! :)
Lloyd
 
lparsons21
OK, decided to up the load. Did a 300 gram load of a China coffee I just got.

PreHeat to 215 ( just an arbitrary number)
Put the beans in and set countdown timer to 18 minutes
1st Crack started @345 degrees F, a 10 degree increase at 7:15 on the timer. That's quicker than I've been doing on the Gene Cafe & Behmor with similar loads. So next roast I think I'll bump the fan a bit and lower the temp a bit in order to stretch the time to 1st crack a bit. I think I want to have 1st crack at about 13 Minutes into the roast. Comments please.

I was using the 'auto' setting because I haven't quite got a handle on this baby yet and observed what it was doing with heat and fan.
Lloyd
 
BenKeith
The beans are going into FC somewhere around 380-390 degrees internal temp. That's set by the nature of the beans and they are going into second crack a little over 400-440 degrees (and that depends on whose article you are reading. The temp readings your roaster is showing has nothing to do with when they actually go into FC and SC, nature and environmental conditions regulate that. That's just showing you your probe placement is wrong, or the probes/electronics is screwed up, not that your beans are going into the cracks at those temps. Your roaster is not changing those temps, it just showing the wrong temp for them.
That is also why you should never use temperatures for a profile from someone else's roaster unless you have some way of verifying there's hits the key points of a profile at almost the identical temp yours does, and that usually ain't likely.

If you want a 10 min FC, you roast for a 10 min FC, doesn't matter is the temp is showing 300 degrees when FC starts at 10 min. Roast by time, sight, sound and smell. The temps are just and extra crutch and required for PID control.
Edited by BenKeith on 10/16/2016 6:25 PM
 
HoldTheOnions
If you study roasting competition profiles you see a lot of similar characteristics. Here is past couple years,

https://www.crops...wcrc-2016/

https://www.crops...tion-2015/
 
lparsons21
Ben, thanks for the feedback. And I know it is just the reported temp that is incorrect for some of the reasons you mention. I understand the chemistry and physics of the roast process.

I'm tracking things as I roast to ensure that the difference between indicated and actual stays consistent. As long as it does I can do the math in my head. And as you noted it really is all about sound, sight and smell. This isn't my first roaster, just the first one with a BT probe and readout.
Lloyd
 
lparsons21

Quote

HoldTheOnions wrote:

If you study roasting competition profiles you see a lot of similar characteristics. Here is past couple years,

https://www.crops...wcrc-2016/

https://www.crops...tion-2015/


Thanks for those. I'm not there yet on these graphs as I haven't started using Artisan yet. With all my previous roasters I've just done manual adjustments and noted them and since the only two with actual temp readouts just do environmental temps I never even considered graphing. I'm not even sure how you'd do it on a Gene or Behmor, I never bothered to look either. I've always relied on sound, sight and smell.
Lloyd
 
appslut
I would forget all you have read and simply roast by sight and smell for a few roasts.

breaking in your new machine takes several roasts and you are simply experiencing new roaster break in...

so take some beans and roast by sight and smell only...

please let us know.


AS

Welcome
 
lparsons21
Thanks for the feedback. I always roast by sight, sound and smell. But I monitor and adjust as I go along too. The goal with the B-2K+ is to get to the point I can pre-program it with Artisan. In order to do that I think I need to document time/temps and so forth as I manually do them. I'm doing that now.

Today I did a 270 gram roast. Based on a post on this forum from someone, I played around with fan off and 2 or 3 setting at some times to pull off moisture. Ran heat at 100% for the 1st 8 minutes, then ran the heat down to 80% with fan off or at 3 at different times until first crack started. Indicated temp at that start was 350 degrees F. Finished out the roast at 60% heat and fan at 2 and got about the middle of 2nd crack. Roast looks great and smells wonderful. I'll know in a day or two how good it is when I use it.

From my observations today and with pulling heat and fan at different levels, it seems to me that I'm getting a significant lag in temp reading from the BT probe or the control panel. Hottop is sending me a new panel and BT probe to see if one and/or the other will fix what may be just a lag.

But it will have to be a few days before I roast again as I've got about 2 lbs of roasted beans and I'm the only coffee drinker here. :)
Lloyd
 
BenKeith
Now, I have a question. I know my approach but I am curios about how others would approach this.
Posted are the last two years of championship roast profiles.
If you wanted to try one, how would you go about it?
Right off the bat, it's very obvious the temps mean nothing, at least not In anything I've used. How many people are going to get a first crack at 177C/351F in their roaster.

Well, other than Iparsons21, his might come pretty close right now.



I can in my Hot Top if that's what I want...


ginny
Edited by ginny on 10/21/2016 6:17 PM
 
Randy G
It is nearly impossible to match commercial roasting machines' temperature readings to a home roasting appliance. Commercial machines have a bean depth which dwarf's most home roasting machines. So you need to extrapolate their marker point temperatures and then adjust your roasting curve to match. It's the best you can do. Even then, very few home roasting machines have the level of control and consistency that a commercial machine has.

Life's too short to drink bad coffee.
 
lparsons21
Randy, I agree. I've had lots of roasters over the years starting with the Fresh Roast 8 and they all suffer from consistency and control to some extent. It would be great if you could get that perfect roaster for the home but then it would cost way more than the ones out there now.

My least roast was extrapolated from a poster's profile from here. I used relative timings for the heat/fan controls and it worked well.

BTW, appreciate you guys sending me the items to try. Great support!! I'm hoping the panel is all it takes to get things right as I'm very much not looking forward to changing out the BT probe!
Lloyd
 
HoldTheOnions
The point of my post was if you study graphs you see some commonalities, so

>Preheat somewhere between 300-400
>Turning point between 1-2 minutes
>Hitting 300f in 4-5 minutes
>Bean ROR curve flattens out in the middle (something's gotta give somewhere, right?)
>Hitting 1c in 7-9 minutes
>Sharper decline in ROR in last 30-40 seconds
>Development time 60-90 seconds
>Development percentage 15-20%
>Total roast time <10 mins

I'm not expert, which is why I was referencing experts. So if not sure where to start, then IMO doing what experts are doing is at least a good place to work out from. Maybe it's not 100% right for you, but why not at least start there?

For example, if you following these and not getting dark enough, then try different approaches to getting darker. With practice you will identify a basic set of metrics that generally gives good results for you and then you can tweak it for different coffees or your mood. It may not taste exactly the same every time, but in my experience it will still very likely taste good every time.

I recently went from popper to baby drum and results were once again really crap. After a few roasts it was obvious I was preheating too hot and hitting 300f too fast. I was hitting every other one of my metrics, but it was still no good. As soon I realized what was wrong and made the correction, I was back in business.

If you don't have data logging, then you can still ballpark it by sight. So start with beans turning yellow in 3-4 mins, then brown in 5-6 mins, 1c in 7-9 mins, and wrap it up in 10 minutes. Work out from there.

Anyway, like I said, I'm not expert.

experts can be wrong and we have zero idea of what they are using or if they are telling the truth... ginny


edit for clarity...
Edited by ginny on 10/21/2016 6:19 PM
 
BenKeith
After 16 years of roasting, I think I have managed to figure out a few things about it and I also think I have all the control I need.

Sorry, didn't mean to hijack this topic.
 
Randy G
HoldTheOnions,

If you are looking for a starting point I have two recommendations

1 - Scott Rao's "The Coffee Roaster's Companion." It is just that- a great guide to a roast profile that is a wonderful starting point.

2 - Mill City Roasters "Roaster School":

Mill City Roasters Roaster School - Ep #1 - Turning Point

Roaster School - Ep #2 - Drying/Yellowing - YouTube

Roaster School - Ep #3 - First Crack - YouTube

Roaster School - Ep #4 - Beyond First Crack - YouTube

Those make a wonderful partner to Scott's book. But still, take all that as just a starting point. If you ask three roasters about the "best" profile, you will be in for a long day as well as getting at least a half dozen answers.

Your sample figures, as an example: I have found that it makes virtually no difference in the curve whether I charge at 350 or 300 in my roaster, and even down to 275 changes little in the BT profile on screen. Any roasting appliance has its limits and beans have theirs as well. Even now I am playing with 225 to 250 charge temps and am about to start slowing the turning point a bit to see if that helps.

Even after 16 years of home roasting I am learning a lot. Learned probably as much in the last year as in the previous 15. When you think you know enough about coffee roasting it is time to sell your roaster and just buy commercially roasted coffee.

Life's too short to drink bad coffee.
 
BenKeith
Randy, Trust me, I'm still learning every time I roast and don't even begin to think I know it all. Like you I have probably learned more in the past two years than the previous 14. I just don't need some schoolboy presentation and it just rub me wrong the way things were presented.
When I asked the initial question, it was out of curiosity, and I stated I already knew how I would do it, I've done it once or twice.
I also know there is a whole lot more to duplicating a roast that just being able to follow the temp curve, which I have to control capability to do almost exactly. It would be near impossible to duplicate a roast without having that roast to sample and compare to. Just having a difference in air flow affects what goes in the cup. If it was just being able to follow a chart line, we all could roast like a champion.
Greanbean has said he has never seen anyone get the control I get with any kind of roaster and has asked me to document and post it so others could see how. One of his later updates to RoastLogger was a change I asked him for and he has sent me a couple special changes I use.
I still don't have it perfected yet and I seems like when the planets change alignment, So does my control and I have to go back and re-tweak things. Because of that, my lack of time so far, and the continuous negative attitude I get from so many over PID control, it just has not made my priority list.
So, we have gotten way off subject from the original topic and I think I've said enough.
Edited by BenKeith on 10/19/2016 11:13 PM
 
lparsons21
For those following this. Randy at Hottop sent me a new front panel and BT probe with instructions to try the panel first. Got them today, changed out the panel and it fixed the issue completely!

I did a light 8oz load and @356 the indication changed to brown and first crack started. It ramped through 356 very fast to 359 so I figure the light load made that happen.

Great support from Hottop and I'm very pleased.
Lloyd
 
HoldTheOnions

Quote

Randy G wrote:

HoldTheOnions,

If you are looking for a starting point I have two recommendations

1 - Scott Rao's "The Coffee Roaster's Companion." It is just that- a great guide to a roast profile that is a wonderful starting point.

2 - Mill City Roasters "Roaster School":

Mill City Roasters Roaster School - Ep #1 - Turning Point

Roaster School - Ep #2 - Drying/Yellowing - YouTube

Roaster School - Ep #3 - First Crack - YouTube

Roaster School - Ep #4 - Beyond First Crack - YouTube

Those make a wonderful partner to Scott's book. But still, take all that as just a starting point. If you ask three roasters about the "best" profile, you will be in for a long day as well as getting at least a half dozen answers.

Your sample figures, as an example: I have found that it makes virtually no difference in the curve whether I charge at 350 or 300 in my roaster, and even down to 275 changes little in the BT profile on screen. Any roasting appliance has its limits and beans have theirs as well. Even now I am playing with 225 to 250 charge temps and am about to start slowing the turning point a bit to see if that helps.

Even after 16 years of home roasting I am learning a lot. Learned probably as much in the last year as in the previous 15. When you think you know enough about coffee roasting it is time to sell your roaster and just buy commercially roasted coffee.


I already said that I studied two whole years of the official results of the Cropster World Coffee Roasting Championships. What more do you want from me? Gossssh.
 
HoldTheOnions
Grin
 
Randy G

Quote

HoldTheOnions wrote:

I already said that I studied two whole years of the official results of the Cropster World Coffee Roasting Championships. What more do you want from me? Gossssh.

Sorry... I was not aware that you already knew everything. If I had known I wouldn't have bothered spending the time putting together the links and writing the message. On the other hand, maybe others would get benefit from my post. Maybe park the attitude in the cabinet next to the Folgers and we can all move on.

Life's too short to drink bad coffee.
 
JackH
I believe the OP's question has been answered and no need to continue. Thanks to Randy for the help with his roaster!




thanks Jack for closing this as I believe it's a bit out of hand too...

ginny

limb
Edited by ginny on 10/21/2016 6:34 PM
---Jack

KKTO Roaster.
 
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