Controlling a Cormorant Roaster with Artisan

Discuss roast levels and profiles for espresso, equipment for roasting coffee.
ronncat

#1: Post by ronncat »

I was on the fence about writing this thread, but with some encouragement from Johan and some prodding by a few others on the forum, I decided to document the conversion of my new Cormorant roaster from manual to full control with Artisan.

I have spent the last 4 years roasting with a Quest M3 that I modified with TC4, an SSR, wattmeter and a few other gizmos so that I could control wattage and fan speed with a push of an Artisan button. When I received my new Cormorant, I marveled at the build quality, and looked forward to having more control of the heat and the option to roast larger amounts. I watched a few YouTube videos, and it bothered me that the person roasting would make an adjustment to the roaster and then enter that adjustment manually into Artisan. I am just too lazy to do that, plus I would probably forget to do it half the time.

So, I first set out and built a custom cart so that everything I needed to roast would be contained on the cart and all I would need to do was plug into an outlet. Then, the real fun began. I researched gas control first and found there are basically two methods to control the flow of propane. First, do like the big dog commercial roasters and use a proportional valve ($$$) or, use a stepper motor and needle valve to do the same thing. Having designed and build my own CNC lathe and mill, I was familiar with stepper motors, so I decided on that route.

Here is the list of parts I ultimately ended up using for gas control:

Pololu stepper motor #1472 - way oversized for what I needed, but go big or go home...
Pololu Tic T500 Stepper motor controller
A random 24V wall wart that I believe supplies 4 or 5 amps
1/8" MNPT 316ss Needle Valve (5000 Psi) Swagelok Whitey SS-ORM2. Ebay find
SDP/SI MXL timing belt pulleys. I bought one in 60 teeth and another with 20 teeth, so I could have a 3:1 ratio
SDP/SI MXL timing belt. Had several of these on hand from previous projects
Phidgets OUT1001 - 12 bit Voltage out Phidget connected to the VINT hub purchased with the Thermocouple Phidget from Johan
Adjustable 0-10 PSI regulator
Various hoses and fittings to connect everything together. Amazon is GREAT for this!!!

So, the first thing I set out to do was to design a method for the stepper motor, needle valve pulley system to operate. Not too difficult. Just some 1/8 aluminum sheet and a bit of time on CAD to design the mount. Then milled it out on my CNC mill and put it together.





One thing to note. I ended up buying three different needle valves for this project. After hastily buying any old valve and finding that it only required about 1/4 turn to go from zero psi to max psi, I started researching. I found that ideally a full turn or even two from 0 - max will give much finer control over gas flow. Took a chance on one from ebay, but found that had about 1/3 turn from 0 -max. Finally stumbled upon the one listed which gives me 2 full turns from 0 - 45 mbar!!!!! My pulley system was designed with a 3:1 stepper motor to needle valve ratio, so that means 6 complete revolutions for the stepper to go from 0 -45 mbar.... pretty fine control.

Once that was set, it was not too hard to program the stepper motor controller to operate from 0 -5 volts input using the Pololu Tic software. Then, created buttons in Artisan Config/Events to output voltages from 0 -5 volts which corresponded with the appropriate desired pressure for the propane gas flow. Since I didn't use encoders or a home on the stepper/valve system, there is always a chance that the calibration could be off since Artisan always assumes it is in a certain spot on fire up. I haven't had any issues in testing a simply scribed a zero line on one of the pulleys for reference. If it becomes an issue, I may add some type of Hall system to give me home.

Well that's it for the gas... Works smoothly and consistently with nice control. Love the way Artisan tracks it every time I push a button :lol:

So now I decided with the hard part done, it was time to do the easy stuff... controlling the fan and drum speeds with Artisan. After playing around with the dials and motor controllers, I decided to entirely bypass the adjustment pots on the Cormorant and use only the controls in Artisan.

For this I purchased some more Phidgets DCC1002 - 4A DC motor controllers. I later found from Johan that the drum motor uses a 6A PWM board, but in testing, I have found the 4A controller to work fine. At first I wired the outputs from the corresponding Cormorant fan and motor control boards into the inputs on the Phidget DCC's. Seemed to work fine for the fans, but not at all for the drum.... Hmmm both Dc motor controllers worked fine using the Phidget's control panel, but the drum motor wouldn't budge when the corresponding command was issued by Artisan.
I scratched my head using every available parameter I could think of.. with no luck. Even posted on HB a plea for help. Must have read every article on Artisan and Phidgets a dozen times...

Then a small miracle happened. A search found this GitHub post:

https://github.com/artisan-roaster-scop ... issues/626

Almost couldn't believe it... Someone with the exact same question with me at the same time! Best of all a solution :D I joined GitHub and fired off a question to Makamo. The next day I had a reply with an Artisan build that addressed my issue. Downloaded and installed it and VIOLA... IT WORKS!!!

I cannot Thank Marko enough for his prompt response and help. Another couple of days and I would have been bald from pulling my hair out :oops:

So I'm done at this point modifying my Cormorant. I have just touched on the details and if anyone needs more info, don't be afraid to ask. I'll do my best to help. Thanks to everyone for their encouragement and help. Here's a few pics of the completed roaster.

Before

Milled Base of DCC controllers

After

Buttoned up

The completed cart

Cormorant in Bed
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Chert

#2: Post by Chert »

Beautiful.
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B2uatk

#3: Post by B2uatk »

Outstanding. I just got my roaster last week and trying to figure out how to connect it and already there is a nice path forward. Not sure why you would have thought twice before writing this outstanding journey:)

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Chert

#4: Post by Chert »

ronncat wrote: One thing to note. I ended up buying three different needle valves for this project. After hastily buying any old valve and finding that it only required about 1/4 turn to go from zero psi to max psi, I started researching. I found that ideally a full turn or even two from 0 - max will give much finer control over gas flow. Took a chance on one from ebay, but found that had about 1/3 turn from 0 -max. Finally stumbled upon the one listed which gives me 2 full turns from 0 - 45 PSI!!!!! My pulley system was designed with a 3:1 stepper motor to needle valve ratio, so that means 6 complete revolutions for the stepper to go from 0 -45 PSI.... pretty fine control.
Looking at this again, I come up with this point of question. Your needle valve reads really hefty - 5000 PSI - but then it is Swagelok and they seem to make serious parts. It seems to me that the gas pressure needed at your stove should be much less at the pipe ID, like .25 PSI max. Where do you measure 45 PSI?
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Brewzologist
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#5: Post by Brewzologist »

Well done! I did the same type of automation of gas, fan and drum with my Huky and have been very happy with it. Now that you've done this I highly recommend you check out Artisan's software PID functions. While I like to drive the actual roast manually, I use the software PID for my warm-up and between-batch-protocols all the time. It's a great way to remain consistent in warmup and frees me to do other tasks while the roaster gets itself ready.

ronncat (original poster)

#6: Post by ronncat (original poster) »

Chert wrote:Looking at this again, I come up with this point of question. Your needle valve reads really hefty - 5000 PSI - but then it is Swagelok and they seem to make serious parts. It seems to me that the gas pressure needed at your stove should be much less at the pipe ID, like .25 PSI max. Where do you measure 45 PSI?
Good catch. I hastily composed this thread during my lunch today. Should have referred to the gas pressure in mbar and not PSI :oops:

ronncat (original poster)

#7: Post by ronncat (original poster) »

Brewzologist wrote:Well done! I did the same type of automation of gas, fan and drum with my Huky and have been very happy with it. Now that you've done this I highly recommend you check out Artisan's software PID functions. While I like to drive the actual roast manually, I use the software PID for my warm-up and between-batch-protocols all the time. It's a great way to remain consistent in warmup and frees me to do other tasks while the roaster gets itself ready.
Will definitely use PID for warm up. I did this with my Quest and Artisan. Now... if I get real lazy, I might just have to automate the entire roast session :D

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BoulderMike

#8: Post by BoulderMike »

To OP: Looks nice/interesting. My Cormorant is being built as we speak. Being a novice here; I have been roasting on an old FreshRoast 500 while waiting for the Cormorant, I have some questions. (1) I like your cart, would like something similar. (2) Are you roasting in a finished/insulated garage? I ask because I was going to roast indoors near a window but my garage is well insulated and fully drywalled. (3) How are you venting your roaster? (4) For those of us who haven't roasted on a more sophisticated roaster like even Huky or Cormorant, can you explain a bit about Artisan and the Cormorant? I don't understand how they integrate exactly, and based on what you wrote above I am wondering if they really don't integrate "seamlessly". You did a lot of work, and I imagine it cost quite a bit, to create a seamless integration between Artisan and the Cormorant. If I don't do that, what does that mean for me in my roasting process? Not sure if I am making sense but I am really asking if there will be negatives in my process which will result in less positive roasting results if I don't customize the process as you did.

Sorry if this makes no sense. I really just want to understand how the process works out of the box, with Artisan/Phidgets, vs. a highly customized process like you built. BTW, I am thinking of purchasing RTD kit stuff directly from Phidgets rather than what Johan provides. Any thoughts on that would also be appreciated. Thanks in advance for any input you might have. Your setup looks really awesome.

ronncat (original poster)

#9: Post by ronncat (original poster) » replying to BoulderMike »

Michael,

Thank you for your kind words. I have a couple of minutes, so I will try to answer your questions best I can. I am very far from an expert in Artisan, Phidgets and Roasting. Pretty much everything I know has been culled from forums such as this one and other sources on the internet. I just try it...if it works, great, if not... back to the drawing board.

I designed my cart so I would have easy access to the bottom of the roaster, could hold a 20 lb propane tank on it and keep it hooked up. And most importantly, so I could wheel it to where ever I wanted in order to roast. I tried it in the house, in the backyard, but mostly in my garage since that is where it lives. My garage is also finished, but not insulated. I rigged up an extension to the vent, so it could easily be directed outdoors, through a window, etc. I'll post a pic when I get a chance... you'll probably get a good laugh out of it. The vent is VERY efficient. There is not a hint of smoke at the roasting area. Even on dumping the beans, I don't have any issues. A bit unlike the FreshRoast where there is no smoke containment. You should easily be able to roast where ever you choose.

There is a ton of information on this site for Artisan. I chose to download Artisan when I moved up from my Gene Cafe to my Quest M3. To me, it serves as a visual indicator of a how a roast is progressing. It is mainly based upon data it receives from thermocouples that are placed in your roaster. It graphs these in real time as the roast progresses. You can directly see how your inputs affect the progress of a roast. Variables such as heat, fan speed, drop temperature, etc all play an important part in the quality of the roast. The more you play, the more you learn :)

In essence, it is the temperature probes that are the most important things to have. You might ask Johan if he can substitute RTDs if you want to go in that direction. All of the automation is icing on the cake, and is not necessary to use Artisan. You can still control all the parameters with the lovely dials that are on the Cormorant, and I might suggest you try that first and get familiar with Artisan. I can't say enough great things about Artisan!!! Best of all its free!!! Of course you may decide as I have to make contributions here and there, and I would encourage everyone to do so.

BoulderMike

#10: Post by BoulderMike »

Thanks Ron, I truly appreciate your taking the time to respond. As to RTD, I asked Johan and he doesn't plan to include the RTD option anytime soon. He said installing the RTD probes shouldn't be an issue as he has the roaster setup where the probes are inserted but the setup for placing them in the roaster is installed and in place when he ships the roaster. I still think I will go with RTD and hope that setup of the probes (installation into the roaster) and the Phidgets is as "easy" as everyone says. I am a retired IT person but not particularly handy like you are with building things. That being said, I am about to embark on a build of an electric guitar from a kit which includes a body and neck, but requires installation of electronics, etc. We shall see how that works out. I am leaning towards roasting in my garage but have been advised not to leave the propane tank in the garage. So, I might just look for a cart and a cover for the cart/roaster and leave in the garage, and purchase a 20' hose to go from the roaster in the garage to the propane tank outside. Not sure about all of that yet. As you suggested, I think now I am going to wait to receive the roaster, see how big it is, etc. and then decide how to proceed. For now I have my regulator hose, propane tank, and when the roaster arrives I should be able to get started. I just need to purchase the probes and phidgets. Anyway, thanks for your response. I have been waiting a long time for my Cormorant and am really hoping it will up my game with roasting. Cheers!