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Skywalker Roasts
Mike_Mathis
Top  #26 Print Post
Posted on 01/06/2024 9:08 AM
I freely admit I had a tougher time than checking with my normal fluid bed. It was as if it was turning brown yet still had a hint of green in it. I also didn't check the trier constantly during that time.

I probably missed it. Hopefully will improve during subsequent roasts.

Infrared seems to be a different animal....just a little.
*Fresh Roast SR800 w/ext tube Phidgets & Artisan
*Kaffelogic Nano 7
*Skywalker V1 (heavily modded)
*2023 BC-2
 
HarryDog
Top  #27 Print Post
Posted on 01/06/2024 11:33 AM

Quote

Mike_Mathis wrote:

I had 3 beans that were charred completely black. All other beans looked great. I figure those 3 went somewhere they were NOT suppose to go. I had 1 bean charred in 1st roast. I figure they somehow sat on heater cage for a few. Just a guess though.


I think this is because beans are allowed to sit on the front face of the roaster between the agitation fins and the front panel, looking at Josh's video. Some elongated bumps, maybe 3 in the bean mass area (Half way to fins) would bounce them off the face plate?
 
HarryDog
Top  #28 Print Post
Posted on 01/06/2024 11:42 AM

Quote

Mike_Mathis wrote:

It was as if it was turning brown yet still had a hint of green in it.
Infrared seems to be a different animal....just a little.


I was fighting this underdeveloped taste with the Auto Roast feature.
AST mode might be the easiest option just to run the roast a little longer, until full manual is used.

I think increasing the charge load might also cause a slightly longer roast time, but will it require more time due to the charge as well?

Once back up and roasting I'm going to try 400g as a test.
 
Mike_Mathis
Top  #29 Print Post
Posted on 01/06/2024 4:17 PM

Quote

Once back up and roasting I'm going to try 400g as a test.


I will up my charge to 400 also. Problem here is I've got to do some drinking before I do some roasting. This stuff sure does taste good on a wet, cold Winter day as I peek outside every once in a while.pouring
*Fresh Roast SR800 w/ext tube Phidgets & Artisan
*Kaffelogic Nano 7
*Skywalker V1 (heavily modded)
*2023 BC-2
 
renatoa
Top  #30 Print Post
Posted on 01/07/2024 2:11 AM
It should definitely be longer, dare I say proportionally.
At any given time, heat is absorbed only by the top layer of the pile, which is directly exposed to radiation.
As the drum rotates, this layer will slip and go underneath, giving up a share of absorbed heat to the inner bean...and so on.

If the heat% remains the same, the time should be longer for more beans to absorb same heat each of them.
 
Mike_Mathis
Top  #31 Print Post
Posted on 01/07/2024 10:56 AM
So if it isn't the timer telling the controller that the roast has reached its target which I can understand with the amount of beans being a variable, is it the rising temperature at the probe from its exposure to the bean mass touching it?

After typing this, I think the answer is obvious [yes].
*Fresh Roast SR800 w/ext tube Phidgets & Artisan
*Kaffelogic Nano 7
*Skywalker V1 (heavily modded)
*2023 BC-2
 
renatoa
Top  #32 Print Post
Posted on 01/07/2024 11:33 AM
Right, at 170-172C the controller commends heater low by 20-25% even if you do a test with empty machine.

Development length (i.e. drop time) is again driven by temperature, according to the table in manual, and in this case the load matters, more beans = longer time to reach the drop temp = longer development
The big mystery to me is how is first crack detected/hard-coded inside the controller profiles matrix, to have a starting point for development... or for the stop, as you like it...
 
Mike_Mathis
Top  #33 Print Post
Posted on 01/07/2024 12:07 PM
I am throwing a slight curveball here. I have only done two roasts on this unit and have not entered the world of cupping yet, so they are both still resting.

Since you have roasted a few and different ways, how would you rate the cup compared to other roasters?
*Fresh Roast SR800 w/ext tube Phidgets & Artisan
*Kaffelogic Nano 7
*Skywalker V1 (heavily modded)
*2023 BC-2
 
renatoa
Top  #34 Print Post
Posted on 01/07/2024 1:54 PM
The last one, about which I wrote 2 days ago, is indeed in the "memorable" class.
It even got me thinking about some modifications to my TO machine as well, to get similar results.
 
Mike_Mathis
Top  #35 Print Post
Posted on 01/10/2024 9:32 PM
My 1st roast on the SW was on 1-4. Yesterday I made my first cup (I'm not a cupping kind of guy, at least not yet) and it was a very tasty cup of coffee. This was a bean I told myself I wasn't going to buy again. Now, all bets are off. According to the display on the controller, this roaster can run a lower RoR through the Maillard phase than I can achieve on the SR800 (especially coming off of DE into the beginning of Maillard), and I think this might make a difference. However, this is 1 roast. I don't want to get too far in front of my skis.
Edited by Mike_Mathis on 01/10/2024 9:38 PM
*Fresh Roast SR800 w/ext tube Phidgets & Artisan
*Kaffelogic Nano 7
*Skywalker V1 (heavily modded)
*2023 BC-2
 
Mike_Mathis
Top  #36 Print Post
Posted on 01/11/2024 10:42 AM

Quote

renatoa wrote:

The last one, about which I wrote 2 days ago, is indeed in the "memorable" class.
It even got me thinking about some modifications to my TO machine as well, to get similar results.


Is this about the Kenyan AA you roasted on 1-5? I have printed out that info and am ready to try this. This would be my first manual roast. My electrical runs ~123V on a 120V grid so I'm wondering if I need to scale back just a bit.

Edit: Plugged my meter in and it's showing 125V. (Accuracy has been verified)
Edited by Mike_Mathis on 01/11/2024 1:34 PM
*Fresh Roast SR800 w/ext tube Phidgets & Artisan
*Kaffelogic Nano 7
*Skywalker V1 (heavily modded)
*2023 BC-2
 
renatoa
Top  #37 Print Post
Posted on 01/11/2024 11:26 AM
Yes, post #21.

Start with preheat and see how far are you from stable 200C, as I was with 55% heater and 50% fan.
To remove the roaster preheat on/off logic influence dial something higher than 200C.
If not there, try 5% +/-, and scale the whole profile up or down accordingly.
Please also notice that I am roasting at 24C/75F ambient.
 
Mike_Mathis
Top  #38 Print Post
Posted on 01/11/2024 8:02 PM
Well.....the roast from post #35 was interesting to say the least. Now I know why these roasters have profile/auto modes. For people like me. I had renatoas sheet as a guide and was spot on for preheat. When it hit the 200° mark it went to 201° and then settled down. Then I put the beans in and planned to wait 1 minute to make my first change, but by then I was out on my skis with high tremps. After that, it was a circus. No matter what I did as far as decreasing heat and increasing fan, the temps jumped up and it was a fight. All told, I tried for a 8:35 roast and dropped at 6:26. The RoR during the entire roast was between 14 and 16. I was trying to lower it but could not. renatoa made the point that the controller only reported this metric once a minute. Cheesy. The beans look great and the W/L is 13%. I don't expect them to be very good, but time will tell. I need to go back to the assist mode for a few more. Those were a piece of cake. I believe my 125V didn't mesh well at all with the numbers I had on paper. Definite inexperience at manual roasting. Live and learn.

I DO believe this: This roaster is designed for 350-400g. If you roast less, it obviously can be done, but you need to really know what you are doing. I don't at this point. I will be trying a 400g batch, but will take a break from the other direction.

Burnt bean report: I had 1 bean charred on the flat side. The Sherlock Holmes in me says that bean sat on something very hot for too long.Shock
Edited by Mike_Mathis on 01/11/2024 8:27 PM
*Fresh Roast SR800 w/ext tube Phidgets & Artisan
*Kaffelogic Nano 7
*Skywalker V1 (heavily modded)
*2023 BC-2
 
renatoa
Top  #39 Print Post
Posted on 01/12/2024 3:00 AM
Spot on for preheat you mean 55% heater and 50% fan, and no on/off from the roaster ?
From what you wrote it seems that 55% was too high for 200C, and the preheat was still under roaster control.
Easy to find this, a beep sound is issued each time when the preheat target is reached and heater is turned OFF.
That's why advised to set a higher than 200C limit, to be sure the roaster logic for preheat is always ON, and temperature is controlled exclusive by modulating power.

16 RoR is never seen on my roaster, not a circus there, rather a rodeo ! Grin
 
Mike_Mathis
Top  #40 Print Post
Posted on 01/12/2024 9:42 AM

Quote

renatoa wrote:

Spot on for preheat you mean 55% heater and 50% fan, and no on/off from the roaster ?


Yes, when it reached 200, it settled down and I loaded the beans. Temp went down for TP then started up and I (through inexperience) didn't catch it in time. My issue was I just didn't believe I would need to reduce the temp so much. I believe I should have went to 40% on heat.

Quote

From what you wrote it seems that 55% was too high for 200C, and the preheat was still under roaster control.


See above.

Quote

Easy to find this, a beep sound is issued each time when the preheat target is reached and heater is turned OFF.


The heater did turn off. The temp started falling. At 197 I started loading beans and then put heater on 50%. That was too high.
The main thing I gleaned from this was quit fiddling with pen and paper trying to record numbers and focus on what the controller readouts are doing. It will be better next time.

Quote

That's why advised to set a higher than 200C limit, to be sure the roaster logic for preheat is always ON, and temperature is controlled exclusive by modulating power.

16 RoR is never seen on my roaster, not a circus there, rather a rodeo ! Grin


You are right. Rodeo would be a better analogy and I was riding Diablo!
*Fresh Roast SR800 w/ext tube Phidgets & Artisan
*Kaffelogic Nano 7
*Skywalker V1 (heavily modded)
*2023 BC-2
 
makermods
Top  #41 Print Post
Posted on 01/18/2024 1:33 PM

Quote

renatoa wrote:

Spot on for preheat you mean 55% heater and 50% fan, and no on/off from the roaster ?
From what you wrote it seems that 55% was too high for 200C, and the preheat was still under roaster control.
Easy to find this, a beep sound is issued each time when the preheat target is reached and heater is turned OFF.
That's why advised to set a higher than 200C limit, to be sure the roaster logic for preheat is always ON, and temperature is controlled exclusive by modulating power.

16 RoR is never seen on my roaster, not a circus there, rather a rodeo ! Grin


I've roasted several batches now in my skywalker, and my ROR is usually 12-14 degrees C per minute; I've been really enjoying the coffee coming out of it but I have been struggling with extending development time and browning. My beans tend to go from green-brown with very little in between, averaging 10-11:15 min roasts with 50% development time, on a 400g charge and 200C charge temp.
 
renatoa
Top  #42 Print Post
Posted on 01/19/2024 2:25 AM
Please can you elaborate more on 50% development time, which sounds completely unusual ?
Are we on same page about development time definition, as the time interval between FC and DROP ?

More details, please: which minute do you have RoR higher than 12 ?
What is the starting power percent ? Auto/Manual ?
 
makermods
Top  #43 Print Post
Posted on 01/19/2024 4:23 PM

Quote

renatoa wrote:

Please can you elaborate more on 50% development time, which sounds completely unusual ?
Are we on same page about development time definition, as the time interval between FC and DROP ?

More details, please: which minute do you have RoR higher than 12 ?
What is the starting power percent ? Auto/Manual ?


I'm so sorry! I misspoke. I meant 50% drying time, 30% browning, 20% development time, HAHA! 50% development time would definitely lead to some "roasty" beans!

My RoR for my first manual roast, which was a washed Costa Rican bean, was consistently 6-7C per 30 seconds, which I guess is 12-14 RoR per minute? Starting power based on your previous posts is 65/65 (fan) and a charge temp of 200C. TP happens around 1:15, with TP temp around 100C. Then I see a pretty constant RoR of 6-7C per 30 seconds, until I start lowering power and increasing fan at the 5:30 minute mark, which usually correlates to around 140C and dry end. Sorry I have my roast book at home (at the office right now) but I"ll post more thorough notes about times and temps when I get home tonight!
 
Mike_Mathis
Top  #44 Print Post
Posted on 01/19/2024 4:58 PM

Quote


My beans tend to go from green-brown with very little in between,


I mentioned this same observation in a past post. It must be the infra-red radiation effect on the beans. It appears to me to be a different way to roast coffee beans from what I have experienced in the past.
*Fresh Roast SR800 w/ext tube Phidgets & Artisan
*Kaffelogic Nano 7
*Skywalker V1 (heavily modded)
*2023 BC-2
 
makermods
Top  #45 Print Post
Posted on 01/19/2024 5:28 PM

Quote

Mike_Mathis wrote:

Quote


My beans tend to go from green-brown with very little in between,


I mentioned this same observation in a past post. It must be the infra-red radiation effect on the beans. It appears to me to be a different way to roast coffee beans from what I have experienced in the past.


I must have missed that post! Haha, I thought it was my colorblindness. How have you been estimating dry end/beginning of Maillard? I have been basing it on smell; I've noticed a distinct sweet corn smell at around 140-150C.
 
Mike_Mathis
Top  #46 Print Post
Posted on 01/19/2024 7:01 PM

Quote

makermods wrote:

Quote

Mike_Mathis wrote:

Quote


My beans tend to go from green-brown with very little in between,


I mentioned this same observation in a past post. It must be the infra-red radiation effect on the beans. It appears to me to be a different way to roast coffee beans from what I have experienced in the past.


I must have missed that post! Haha, I thought it was my colorblindness. How have you been estimating dry end/beginning of Maillard? I have been basing it on smell; I've noticed a distinct sweet corn smell at around 140-150C.


Post #26 is where I mentioned it. Smell is a great way to tell. Look for it around 150C.
*Fresh Roast SR800 w/ext tube Phidgets & Artisan
*Kaffelogic Nano 7
*Skywalker V1 (heavily modded)
*2023 BC-2
 
renatoa
Top  #47 Print Post
Posted on 01/20/2024 2:07 AM
sniff the transition from fresh grass to hay
 
renatoa
Top  #48 Print Post
Posted on 01/23/2024 2:57 AM
Another senior moment during last roast, another lesson to share.

This story is especially intended for those who have "learned to love the bomb", i.e. the manual mode, and even brave enough to tackle the automatic stop of roasting based on reaching a certain value.

So, the story starts with last roast FC happening at 179C degrees, at 6:45 moment.
As usual, that moment I am dialing an auto stop roast value for 8C degrees development, in this case intended to set this value at 187C.

By accident, I was distracted, with my finger resting on the minus key, to decrease the auto-stop value from the default 230... and suddenly I hear the beep announcing the end of roasting ! Shock
When I look at the display... 183C, the auto-stop has advanced too far, reaching the current bean temperature, stopping the timer at 7:00, so only 15 seconds into the development phase...

Frozen... trying to think as fast as I can what to do... restart roast or let it go...

Decided to let it as is, so started a timer to see what happens... time pass and, surprise, no sign of temperature drop ! 30 seconds passed and still steady 182C, and beans cracking happily...
After 30 seconds, when the temperature finally dropped to 181C, I said 45 seconds of development was acceptable, ie 10% DTR, so I opened the drop door.

To my surprise the roast turned out as good as it gets, in this troubled context.
Even in the cup today I was delighted to have no cardboard flavor, as is usually preached as a sign of the baked beans apocalypse... when the damn flat zero RoR happens during development.

Now I think to try again this recipe, but in a controlled way, i.e. voluntarily lower the heater during development, to force sinking the RoR on the finish as much as I can, but above zero... Grin
Edited by renatoa on 01/23/2024 12:55 PM
 
HarryDog
Top  #49 Print Post
Posted on 01/23/2024 11:47 AM
First 400g roast 13% looks like I need to put some more heat into the Drying stage.
Roasting using buttons in Artisan, Kind of liked that. Red is internal probe, black is the TC I added.
Any other comments?

I'm cleaning that graph up some. Removing TC probe and Ambient curves, not really needed.
What about the Fan & heater changes and curves? I like the dots on the LCD change lines and the position of the curves.
Can I have the Heater & Fan changes show at the right levels with the dots you can click on and take any guessing out of the equation?

Tried to clean this picture up and provide more useful data.
HarryDog attached the following images:
sw-400e.png edited.jpg
Edited by HarryDog on 01/25/2024 1:08 PM
 
Mike_Mathis
Top  #50 Print Post
Posted on 01/23/2024 8:46 PM
If I see correctly, your TC is recording DE at ~137 and FC at ~165. Interestingly, my TC which is located just about where the "4" is in Josh's video where he wrote 340 on the plexiglass, reads about as much above the thermistor as yours reads below. It also appears the gap widens the higher the temps get. Man, am I confused! I'm curious where your TC is located concerning the video in reference.

Your Artisan button configuration looks good. I believe the filter fan has four settings on the controller. Do your buttons change the rpm's or does it come on and operate at a set speed only?

My last roast on 1-18 was a Guatemalan bean from Antigua that I dropped believing it was about 13.5% w/l. Upon weigh-out, it was 11.4% yet the ground color looks in the 14-15% range. It makes me wish I had a coffee roast color analyzer. I'm scratching my head believing it was a miss that tastes good in the cup. It tastes like a 14+% roasted coffee.
*Fresh Roast SR800 w/ext tube Phidgets & Artisan
*Kaffelogic Nano 7
*Skywalker V1 (heavily modded)
*2023 BC-2
 
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