Arc 800g Sample Roaster - Page 2

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

Postby simplycoffie » Mar 16, 2019, 9:53 pm

TomC wrote:I'd be surprised if the Arc 800g has a thin probe. I picked up a 500g Santoker several months back and even it's BT probe is quite thick. Seems to be a common theme with some of these smaller Chinese roasters.


totally correct on the thickness of the probe, it comes to be 5mm probe, although my arc is made in the USA though (New York)

simplycoffie

Postby simplycoffie » Mar 16, 2019, 10:24 pm

katatak wrote:@ OP, did you resolve your issue? What is your take on the Arc 800g?

Anyone else have experience on one? Thank you for your input, pros, cons, etc.


Hello katatak, so here is what happened.

I called Arc asking about my problem and wish to find a solution. I asked about the possibility of swapping in with a thinner probe for better accuracy, they said i could but would have more noise(if using datalogger) and would actually make the pid more skippy.

so to answer your question, no, my problem has not been resolved, i just adapt to the way the machine responds, and plan accordingly.

Here is my take on the Arc 800g
Pros:
1. setup is easy, there are only 3 pieces to install after unpacking, (exhaust fan, exhaust tube, cooling fan tube) which is easy.
2. Total pre-heat time is about ~20min. it can be faster, but from my experiment, 20 min pre-heat time will let me have a consistent roast from the 1st batch till im finished, anything less i find the first batch takes too much heat from the drum.
3. PID have 2 different display setup, so depending on your liking, it can be set to whichever you prefer. Both display theme shows bean temp. in-drum air temp, exhaust temp, and Time, the difference is in the display orientation.
4. adjustable drum speed
5. even roast, which shows good heat transfer from the drum and air.
6. no beans get stuck inside the drum, some times there will be a couple of straggler beans that refuse to come out when ejecting, but so far i have not had this happen to me.

Cons:
1. drum rotation noise, you will hear a clicking noise if you have the drum speed set at medium range, and it gets progressively louder the faster it spins, it's not obnoxious, but it's audible.
2. unsteady gas pressure, first 30 min after ignition, the gas pressure will gradually drop till the flame cuts out, unsure of the issue here, part of me thinks the reason is due to the propane tank has not yet reached a steady outflow pressure, after the first 30 min, gas pressure will be steady.
3. gas pressure knob, its a nice design with a lock on it so you don't accidentally bump it. the problem is its too sensitive, you could go from max pressure to zero in less than a half turn of the knob, so adjusting gas pressure becomes somewhat tedious, got to be very careful.
4. PID/temp probe, as my original post stated, the temp reading on the pid doesn't read smoothly, it skips a little.

Summary:
i've created lots of great coffee from this sample roaster, the operation is as easy as it gets, build quality is really nice as well, for the price($3800)its a great beast nonetheless! as for the cons i listed, im sure i'll get used to it in time then it won't be a problem for me later. I hope this is of some help for you and wish you the best of luck in search of your own roaster.

User avatar
hankua

Postby hankua » Mar 17, 2019, 1:15 am

Great write up on the Arc Eric!

I think some of the initial issues could be solvable or fixed with some tinkering.

The drums clicking could be a loose chain or rub in the back; or the front of the drum shifted a bit during shipping and is rubbing on the faceplate. Adjustment needed if that's the case.
Not sure about the gas pressure, maybe a higher 4-5 kPa regulator?
Half a turn on the gas knob is fine, it's a problem it the results are jerky or imprecise. Possibly could be upgraded?
PID display looks to be custom, I'd reach out the factory in China for some advice.
You might try putting a thermocouple in one of the screw holes near the bean pile side and see how it correlates to the display temp. Then retrofit a permanent solution if desired.

katatak

Postby katatak » Mar 17, 2019, 1:53 pm

Thank you Eric, that was very indept!

A couple of questions...I haven't found very much information on the Arc, except for the website which doesn't go into a lot of detail. I've emailed them but have not heard back yet (the weekend got in the way).
1. Double or Single walled drum? (the website doesn't mention this)
2. How many roasts can it handle in a day, back to back?
3. Customer Service: what is your rating so far?

Thanks again!

simplycoffie

Postby simplycoffie » Mar 18, 2019, 12:27 am

hankua wrote:Great write up on the Arc Eric!

I think some of the initial issues could be solvable or fixed with some tinkering.

The drums clicking could be a loose chain or rub in the back; or the front of the drum shifted a bit during shipping and is rubbing on the faceplate. Adjustment needed if that's the case.
Not sure about the gas pressure, maybe a higher 4-5 kPa regulator?
Half a turn on the gas knob is fine, it's a problem it the results are jerky or imprecise. Possibly could be upgraded?
PID display looks to be custom, I'd reach out the factory in China for some advice.
You might try putting a thermocouple in one of the screw holes near the bean pile side and see how it correlates to the display temp. Then retrofit a permanent solution if desired.


Thank you for your kind words!

Ahh! Brilliant thinking, how i did not thought of the drum shifting during shipping/ lose chain/ or possibly not enough grease on the rotor.
I have the supplied low-pressure regulator installed on my setup, didn't know i could buy specific kPA regulator, thought there's only low and high pressure.
The gas knob is not jerky at all, in fact, it's so smooth and can be turn with a very light touch, very accurate as well when adjusting. I don't think it bothers me enough to want to tinker with it, still, thanks for the advice!
I will definitely try to stick a thermocouple into one of the screw hole near the bean pile and see how it compares.

Great advice!!! Really appreciate your help :D

simplycoffie

Postby simplycoffie » Mar 18, 2019, 1:02 am

katatak wrote:Thank you Eric, that was very indept!

A couple of questions...I haven't found very much information on the Arc, except for the website which doesn't go into a lot of detail. I've emailed them but have not heard back yet (the weekend got in the way).
1. Double or Single walled drum? (the website doesn't mention this)
2. How many roasts can it handle in a day, back to back?
3. Customer Service: what is your rating so far?

Thanks again!


I totally understand your concern about not able to find much information with it, that is exactly how I felt when I was researching, to be honest, I really took a huge leap of faith with the Arc, there is probably only a handful of videos about the Arc on youtube. What made me commit was the fact that it has everything a big roaster have, cyclone, air control, air flow meter, chaff collector, tryer, and most important of all, independent blower motor for cooling trey! I made a phone call asking some last minute questions about the roaster, then comes the purchase. (it integrates with Artisan pre-installed, and cropster as well, you do need to purchase additional phidget for cropster)

1. I believe it is single walled (if my memory serves me good), but don't hold me up for it :? I will call them tomorrow to find out.
2. I actually went through a whole day of back to back roasting with it nonstop today, and it performed really well. One thing to keep in mind is to empty out the chaff collector every 6 batches of Washed roast(based off of 100g/batch), 4-5 batches of Natural roast(based off of 100g/batch), the collector is a bit small I would say probably a good 60oz volume.
3. My rating is 5 of 5 star rating! I had to call them twice about some problem I had with the roaster, the reception transfers me to their roaster engineering team. First call was about how to set temp reading from F to C, I am more confident roasting in C, the tech instructed me step by step on the phone from taking the drum cover off to switching wires to resetting, to put everything back together, and also sent me an email with instructions if I choose to change it to F again. Second call was about the drum rotation clicking noise, after explaining what I am experiencing, they asked me to video the problem and email to them for diagnose. I received a same day reply after their head engineer had review the video, telling me the noise is coming from the motor which is within their spec, and assured me the roaster is safe to operate, at any point if I feel the motor is faulty they will send me a new motor with no charge as well as instruction on how to swap out the motor.

It kind of sounds too good to be true, but it is my honest opinion and a real story of my experience with Arc. :D

ps. I would wait until Monday afternoon for their reply if not you can always call them, they always answer their phone call.

I hope this is of some help to you, let me know if you need any more information, as infos for the Arc is not easy to come by on the beloved internet :lol:

katatak

Postby katatak » Mar 18, 2019, 1:25 pm

@simplycoffie
i did some research that the arc is manufactured by HB, and a german distributor confirmed it was a single-wall :(
wishfull thinking maybe the arc is modified? If it's a double-walled drum i will buy it right now. it sounds like everything a new roaster could ever wish for :lol:
i'm on the west coast, hoping to hear back from them soon or i'll give them a call.