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Skywalker, the ALM chinese one pound roaster
renatoa
Top  #26 Print Post
Posted on 11/29/2023 9:13 AM
Made to order, same for me. Ordered on 10/26, shipped on 11/14
 
HarryDog
Top  #27 Print Post
Posted on 11/29/2023 9:29 AM
That probably won't arrive before Christmas then? Was looking forward to roasting on it over my Christmas break. Oh well.
 
Mike_Mathis
Top  #28 Print Post
Posted on 11/30/2023 5:45 PM

Quote

renatoa wrote:
However, the way how cooling tray is built, as a tin perforated tray into another plastic tray, allows extraction of the beans immediately after drop, moving them to a separate cooling unit, and performing back to back roasts.
For how long... try on each own risk... as already stated, there are parts of front panel made entirely of plastic!
Probably a heat resistant plastic, I guess... because it's only a millimetre steel plate between that plastic and the hot air inside oven !


Hopefully, the plastic is the same as used in the FreshRoast SR roasters. That plastic gets super hot, but it can take the heat. It is a brittle plastic by design and chips easily but does not tend to warp easily.
*Kaffelogic Nano 7
*Skywalker V1
*2023 BC-2
 
allenb
Top  #29 Print Post
Posted on 11/30/2023 5:54 PM
I hope that as well. I know what you mean on the bakelite looking plastic used on the freshroast. I've also cracked that brittle plastic more than once. It seems to have an internal structure similar to ceramics with a glossy exterior and once broken, it has a rough texture similar to when cast iron or ceramic material is broken.
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
 
Mike_Mathis
Top  #30 Print Post
Posted on 11/30/2023 7:12 PM
Another interesting characteristic of this plastic is the ability to drill and tap threads in it. When I put a 300mm thermocouple in through the chaff collector lid, I drilled it and used a tap to thread a very secure mount. No oil was required while tapping. Of course, I also threaded the shoulder on the probe. When drilling it creates dust.

Edit: I need to clarify in the event someone has a thermocouple mounted in the lid of their SR roaster and would like for it to not flop around. When I threaded the tap into the lid, I went slow and backed out often to clean it. Even though the material is brittle, it tapped well following the caveats mentioned above.

End hijack of Chinese roaster thread.
Edited by Mike_Mathis on 12/01/2023 11:30 AM
*Kaffelogic Nano 7
*Skywalker V1
*2023 BC-2
 
renatoa
Top  #31 Print Post
Posted on 12/01/2023 1:45 AM
Nope, this is not bakelite, I know that kind of matter, grown up with it.
Was dominant 50 years ago, even if not a "plastic" as the today meaning.
Made from coal tar and wood alcohol, not from petrol.

Also, surely is not teflon... rather a polyamide type.
When drilled it creates long helix strips.
Good threading capabilities, the front mask is mounted in this plastic by 6 self-driving screws.
 
Mike_Mathis
Top  #32 Print Post
Posted on 12/01/2023 9:08 AM
I watched a YouTube video of the unboxing and didn't see a long-handle hex wrench for removing the drum. Any ideas of the size and length needed?
*Kaffelogic Nano 7
*Skywalker V1
*2023 BC-2
 
Piotrkurak
Top  #33 Print Post
Posted on 12/01/2023 10:02 AM
There are numerous high temperature "plastic" compounds available today, the really high temp ones made from silicate (?) feed stock all with various melting points and machinability. More parameters means more expensive. The drilling helix indicates you were at optimum feed with a not chip breaking lead angle.

Will this one get reassembled and produce a repeatable roast of at least 500 grams? 1pound plus, American?

My searching found the manufacturer by mistake. List price was € 150 each for quantities above 1,000 call for lead time.
Edited by Piotrkurak on 12/01/2023 10:16 AM
 
renatoa
Top  #34 Print Post
Posted on 12/01/2023 12:03 PM

Quote

Mike_Mathis wrote:

I watched a YouTube video of the unboxing and didn't see a long-handle hex wrench for removing the drum.
Any ideas of the size and length needed?


Is drum removal supposed to be regular user maintenance operation, to provide necessary tools? Grin
Why would you remove drum (frequently) ?

Unscrewing of the three drum bolts requires either an ordinary T25 bit from a screwdriver kit, hand operated with a small handle, mine is 8 cm long, to fit in the 16 cm drum diameter... either the T25 key from an Allen wrench kit.
Drum is 21 cm deep, not a difficult operation, after front panel is removed, you can even operate blindly, if good fingers.
 
renatoa
Top  #35 Print Post
Posted on 12/01/2023 12:25 PM

Quote

Piotrkurak wrote:

Will this one get reassembled and produce a repeatable roast of at least 500 grams? 1pound plus, American?

My searching found the manufacturer by mistake. List price was € 150 each for quantities above 1,000 call for lead time.


There is a vague warning somewhere about being careful if trying 500 grams loads, without details about what exactly the user should be aware...
The drum size (D16 L21 cm 4.2 litres volume) allows loads up to 700 grams, according to the 1:6 rule, but that rule is for the true drum roasters, with heat source outside.
In this case the heat source take at least 1/4 of drum volume, so is hard to respond to the "repeatable" part...

The power seems to be enough... if the Auto modes are using maximum 70% heat for 350-400 grams optimal load.

I would rather contact the primary manufacturer for a collaboration proposal for a much serious machine control, his control panel and operation philosophy is the weakest link in the chain.
 
Mike_Mathis
Top  #36 Print Post
Posted on 12/01/2023 1:56 PM
I'm wondering if there is an area available to install bean and exhaust thermocouples. Use the built-in controller (in manual) for control and Artisan for visual monitoring and logging data.
*Kaffelogic Nano 7
*Skywalker V1
*2023 BC-2
 
renatoa
Top  #37 Print Post
Posted on 12/01/2023 3:20 PM
There is no ET channel need for such machine, using full radiant heating inside the drum.
Sure, it could help you with hints about approaching FC, but personally I wouldn't waste a probe, and attention, for another diversion during roast.
Attached is the picture of the internal panel, support for the motor/drum flange, with bearings.
The small black hole in the top is the hot air exhaust. Probably there is the best place for an ET probe, if someone insist.

The actual BT probe is not a TC, but a rezistive type sensor, not sure yet if RTD (Platinum) or a NTC (thermistor).
It has a resistance close to 5k at ambient temperature.
My guess is that tapping their BT probe, as is now, in circuit, and processing the signal to feed a customized TC4 board is not a rocket science job.
Even control can be diverted to an external system, TC4 or similar. The machine control use a standard triac, mounted on its own heatsink, with typical connections to the heater.
All you have to do is to add the necessary optocoupler(s) to turn it into a SSR like the cased commercial versions.
renatoa attached the following image:
whatsapp_image_2023-11-30_at_122309.jpeg
Edited by renatoa on 12/01/2023 3:48 PM
 
Mike_Mathis
Top  #38 Print Post
Posted on 12/01/2023 4:51 PM
I'm glad to hear you say the ET probe is not necessary. I only have one probe on my SR800 and it suffices. Changing the control scheme is above my pay grade, so I hope to install a probe close to the existing bean temp probe and monitor for Artisan. I just like the data that Artisan provides. Thanks for the info you are providing. You seem to be very smart on this stuff.
Edited by Mike_Mathis on 12/01/2023 10:43 PM
*Kaffelogic Nano 7
*Skywalker V1
*2023 BC-2
 
renatoa
Top  #39 Print Post
Posted on 12/02/2023 4:37 AM
Similar machines exist for some years, but prices were still in the prohibitive ballpark, at least for me... and also shipping, make them unattractive.

http://vi.aliexpr...13031.html

Having dimensions close to Skywalker, this model is rated for 600 grams, using a smaller heater, of 800W only.
 
HarryDog
Top  #40 Print Post
Posted on 12/02/2023 8:37 AM
Hello renatoa, how was yours shipped, by UPS? I never seen a choice for the shipping or I would not have bought this knowing it was UPS, they often charge Brokerage fees well beyond the cost of the item. Starting to get a bad feeling about this.

I also see some notes on the shipping?
Import charges are due for this package.
Duties or taxes are due on this package.

This is going to be different for every country but did you pay any extra charges and about how bad?
 
renatoa
Top  #41 Print Post
Posted on 12/02/2023 10:19 AM
Mine Fedex.
A friend bought from other seller, who sent by DHL.
Btw, the other seller has stock, instant shipping, no wait times.

For EU countries is VAT, 19% for my country.
This amount is subtracted from Aliex display price and paid by me at customs.
Thus if I see $450 on Aliex, I know that $90 is VAT... so I paid $360 at order time and $90 at my customs.
No idea for US, where each state has own taxes.

About shipping... free shipping should be free, worldwide... as in free lunch smile
However, here the carriers charge about $11 for customs paper processing and handling. All of them.
 
HarryDog
Top  #42 Print Post
Posted on 12/02/2023 11:46 AM
This looks very bad, looking at the UPS Brokerage rates for 10KG package?
This could be $900CAD just for Brokerage almost twice what I paid for it.
What are the rules if I refuse shipment?
Any UPS shipping experts reading this?
I think I need some advise.

I tried to contact the seller but it might be 12 hours or days before I reach someone.

Not sure if any of these new shipping services use their own brokers for a more reasonable fee?

When I Google Brokerage for UPS Worldwide Expedited it said it does not charge but if i download the Rates pdf it has very high rates in the list for UPS Worldwide Expedited, I guess I just have to wait and see.
Edited by HarryDog on 12/02/2023 1:56 PM
 
renatoa
Top  #43 Print Post
Posted on 12/03/2023 3:46 AM
Some usability thoughts... for the two ends of the roasting process, charge and cooling.

Charging: we want it fast and no beans spill.
The roaster opening is small and don't make this task easy... the provided scoop also is too small, and the rounded edge don't match optimally the roaster opening, easy spilling on scoop sides if you don't pour slowly.
Having at most 100 grams, so you need four moves for the whole charge, combined with the slow pour speed, make the charge take about 30 seconds, not so good.
Fortunately, the solution is simple. Build a custom chute from a ... pizza slice tray Grin cutting the center angle part to the size of the roaster opening.
Alternatively, you can build a custom square scoop, from a 10 cm side tin can, something like in the attached image.
Bend the round corners with some pliers to make them right angled, and to fit perfectly the roaster opening width (about 9 cm) and you have a scoop able to load 400 grams of greens and charge in a single move in less than 10 seconds.

A notice about having senior moments... as I did Grin
One of the roasts, while charging beans, I heard unusual sounds, and, looking down I found that I left drop door unlocked, so the beans were spilling on the table and floor... best time for a panic moment !
In such moment, you should stop charging beans, pull the cooling tray, to collect the rest of the beans still in the drum, then clean the mess, and resume roasting.
This is the reason I think it's a good idea to keep the cooling tray half open all the times!
Never know when you are in an emergency and need an instant drop, with the least mess around.
The cooling compartment is completely separate from the roasting oven, so letting it half open will not inflence heat dynamics.
renatoa attached the following image:
image_2023-12-03_134721295.png
Edited by renatoa on 12/14/2023 9:23 AM
 
renatoa
Top  #44 Print Post
Posted on 12/03/2023 4:30 AM
Cooling
If not aware, you can experience a panic moment at drop time, because apparently the cooling tray locks and don't move.
This is because of two factors combined: the cooling tray has a vertical play, and the roaster rubber pads are not high enough to compensate this play.
The outcome: the cooling tray front bottom edge rubs against the workbench, and most probably will lock if the surface is rubbery.
There are some fixes:
- raise the roaster body using additional taller pads;
- place the roaster at bench edge, with the tray suspended outside
- grab one the bars/handles in front of drop door, and raise the roaster just to unlock the tray, then release.

Indeed, initially wondered what is the purpose of those bars, then found this answer Grin
Funny thing to notice, some units, like the one received by sloppyjosh, are missing those bars !
Picture of sloppyjosh unit missing the bars in his reddit review: https://www.reddi...mpression/

Except this small quirk, the cooling assembly does its job flawlessly, you should be able to touch the beans with naked hand, i.e. 60C, in 2-3 minutes.
As I already wrote, the metal part of the tray can be excerpted any moment and beans moved in a separate cooling unit, if you want to do back to back roasts faster.
renatoa attached the following image:
image_2023-12-03_122841296.png
Edited by renatoa on 12/03/2023 10:08 AM
 
renatoa
Top  #45 Print Post
Posted on 12/05/2023 8:23 AM
Today roast was much more close to what I get from my other machine.
Big beans, fully developed, the heat penetrating to the core.
Below you have the transcript of the roasting notes.

Honduras Capucha
start with PHT@200C, then set htr to 60% and fan to 60%
1:10 126C TP
2:00 131C
3:00 142C R11
4:00 152C R10 HTR55 F70%
5:00 161C R9 HTR50 F80%
6:00 169C R8 HTR45 F90%
7:00 176C R7
7:30 181C FC
8:52 189C DROP, DTR 15.4%

250 grams in, 215 grams out, 35 grams loss = 14%, average for a medium roast, as the outcome looks.
 
renatoa
Top  #46 Print Post
Posted on 12/06/2023 4:32 AM
To anyone listening to mesmerizing siren song of computer assisted roasting, a note of caution: this is not that kind of machine, to be driven... as a car.

There are two main peculiarities that must be well understood about this machine:
- it has very high inertia, almost as a commercial drum, but due to different reasons, in this case is the lamp/heat source inertia, not the drum mass accumulated heat
- it is NOT a hot air machine, which implies a completely different way of thinking than the rest of the roasters, who obey to the thermodynamics heat transfer laws of a body immersed in a hot environment, as discussed in the "Well tempered..." thread.

This not means that acquiring data from the roast is useless, conversely !

But not use this data for investing effort for real time driving/PIDing this machine, because will be, as other user wrote in his thread on same subject ... "a fool errant". You are driving a "Titanic", not a jetski.
The best use I see from the data collected in a roast, is to understand the machine response, and plan carefully in advance the next roast.
Roasting with Skwalker means only few power changes, not many... probably 3-5 are more than enough... most important is now when to change, rather than how much. Same for gas drum roasters.
Another hint that Skywalker ... walks... different than a hot air machine is the heat steps magnitude... 5-10%, same as for gas machines.
Lol, for my machine convection I can even keep power constant same level as is at dry end, and have a good roast.
5% is usually the total amount of power lowering I am doing during the 4-5 minutes of browning, in 1% increments, from 62-64 to 58-60.
If I would change minus 5% in a single step, the RoR would collapse in the negative values realm in 15-20 seconds !

So, for this kind of planning data collected in a roast using sloppyjosh work is invaluable for archiving and post analysis. Thank you !
 
renatoa
Top  #47 Print Post
Posted on 12/11/2023 2:55 AM
All the posts related to "Skywalker roaster mods" were moved to the new thread just created, with that name.
 
Lostx403
Top  #48 Print Post
Posted on 12/11/2023 11:56 AM
My unit is on the way and I'm in Canada as well, UPS tracking outlines the customs/duty is $38.53 CAD. Which sounds about right, I paid around $430 CAD for the unit itself. Supposed to be delivered Friday.

Quote

HarryDog wrote:

This looks very bad, looking at the UPS Brokerage rates for 10KG package?
This could be $900CAD just for Brokerage almost twice what I paid for it.
What are the rules if I refuse shipment?
Any UPS shipping experts reading this?
I think I need some advise.

I tried to contact the seller but it might be 12 hours or days before I reach someone.

Not sure if any of these new shipping services use their own brokers for a more reasonable fee?

When I Google Brokerage for UPS Worldwide Expedited it said it does not charge but if i download the Rates pdf it has very high rates in the list for UPS Worldwide Expedited, I guess I just have to wait and see.
 
HarryDog
Top  #49 Print Post
Posted on 12/11/2023 12:14 PM
Note that the price the seller puts on the invoice will save you from UPS crazy brokerage as far as I can tell.
I'm not an expert on UPS shipping but have been stuck with this before and would just prefer to not ship with UPS when possible.

So the customs price was below the UPS limit if it matters suggestion from the seller was that it might, they tack a COD fee on over and above the listed fees on the site. I can live with that.
Edited by HarryDog on 12/11/2023 12:58 PM
 
renatoa
Top  #50 Print Post
Posted on 12/12/2023 7:57 AM
Another findings I want to share, that shows once again that roasting using radiation is a different beast than the other designs, and the increased importance of accurate beans temperature measurement for such machine.

Trying to spy the various preset profiles logic, with empty machine, no beans, arrived to a (not so) surprising finding, but still surprising for me, after years of convection roasting.
Short story: heat is mainly in the beans, not air, not walls, not drum.
How I found this...
Dialed the lightest program P11, for natural light roast, and let it run, without beans.
The roast start parameters of the automate: preheat 200C, heater 65%, air 65%
As expected, and stated earlier, somewhere in the 170-172C ballpark, the automatic logic drop the heat to 40% and raise the fan to 90%.
With these parameter the temperature (without beans) stopped increasing somewhere in the 178C neighborhood, with small oscillations 177-179C.
Without an increase for the next 15 minutes, the automate triggered a timeout, cut the heat and started cooling.
Using this program three times so far, and knowing that with beans the temperature goes to 194C where is the P11 program cutoff... you imagine my surprise to find that 40% heater and 90% fan alone are unable to heat the empty machine beyond 179C !
Thus, during a real roast the heat measured by probe comes mainly from the beans, with minimal environment influence, unlike any other designs known so far.
This is in line with the black body radiation absorption principle of Planck: the darkest object around the radiation source takes the most of heat.
First the beans, in the browning phase, then the gray tin of drum, the last is the air, because is transparent.
Yes, clean air does not heat from infrared rays! During preheat the probe senses air temperature that takes heat from the gray drum, by convection, not from the lamp.
If the drum would be made from shiny polished stainless steel tin, would be even harder to heat the machine.

All the above explains the very low value for FC of this roaster, in the 182C ballparks, is not about a bad probe calibration, but the lack of an environment hotter than the beans, influencing the measurement.
 
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