Arco by goat story - Page 41

Grinders are one of the keys to exceptional espresso. Discuss them here.
LObin
Posts: 1770
Joined: 7 years ago

#401: Post by LObin »

loscorrales wrote:That's a mess :(
I was wrong. The catch cup is indeed powder coated aluminum with 2 press fitted plastic inserts.
LMWDP #592

LObin
Posts: 1770
Joined: 7 years ago

#402: Post by LObin »

There's a brand new Arco with base and travel case on the Buy/Sell forum at the moment for way less than what you'd pay for, directly from Goat Story.

I would get it if I didn't already own one. Great design with a grind quality that punches way above it's price point.
LMWDP #592

ethiopianbuffman
Posts: 137
Joined: 3 years ago

#403: Post by ethiopianbuffman »

Can you put the kinu burr in the arco?

LObin
Posts: 1770
Joined: 7 years ago

#404: Post by LObin replying to ethiopianbuffman »

I've searched for this but haven't been able to find answers on other compatible burrs. Although... unless the interest is towards the brew burr, I don't see why someone would want to switch the Arco burr sets to the Kinu M47 espresso burr since it's basically the same burr set.
LMWDP #592

PeterTheGoat
Posts: 37
Joined: 3 years ago

#405: Post by PeterTheGoat »

ethiopianbuffman wrote:Can you put the kinu burr in the arco?
Yes you can, but I don't know why you would want to.
I make 2-3 pour-overs and one espresso per day with my Arco and haven't found a need to change the burrs for something different to grind these whatsoever.

halfro_american
Posts: 2
Joined: 2 years ago

#406: Post by halfro_american »

Can anyone with the 110v unit, or Peter, confirm what the power draw (amperage & frequency) is on the 110v unit? I'm interested in buying one of these and for part of the year I'll be using it overseas where I'll be plugging into 220v outlets.

I know I'll need to reduce from 220v, just curious if I'll need a beefy transformer or one of those smaller step down converters to protect the motor.

Thanks in advance!

renatoa
Posts: 766
Joined: 7 years ago

#407: Post by renatoa »

Label on the bottom says 200W whatever is the voltage, only the motor winding is different.
So you should look for a 200W auto-transformer, not that bulky... check for something like equivalent this on your market:
https://elsales.ro/stabilizatoare-de-te ... negru.html

Beware, these transformers are reversible !
I mean they works both directions... and if wrong connected the 110V side to a 220V mains, you will get 440V on the other side ! :D

Frequency is other story though... an EU version motor will spin faster in US, by 20%
So the 350 RPM will be actually 420 RPM. And viceversa, for US units used on 50Hz, RPM will be reduced to 292.

PeterTheGoat
Posts: 37
Joined: 3 years ago

#408: Post by PeterTheGoat »

halfro_american wrote:Can anyone with the 110v unit, or Peter, confirm what the power draw (amperage & frequency) is on the 110v unit? I'm interested in buying one of these and for part of the year I'll be using it overseas where I'll be plugging into 220v outlets.

I know I'll need to reduce from 220v, just curious if I'll need a beefy transformer or one of those smaller step down converters to protect the motor.

Thanks in advance!
I would recommend you get a switching inverter: they are cheap and compact.
The 200w rating on the bottom of the grinder is calculated according to certain regulations.
The load I measured with our special "grinder torture roast" (a very gummy light roast) was around 160w. You are very unlikely to ever load it up to more than that.
So I would recommend a 200w or 250w switching inverter.

marcism
Posts: 131
Joined: 11 years ago

#409: Post by marcism »

PeterTheGoat wrote:Yes you can, but I don't know why you would want to.
I make 2-3 pour-overs and one espresso per day with my Arco and haven't found a need to change the burrs for something different to grind these whatsoever.
Do you find the grind is always at the same marking for each style when you change back and forth between them? I've got my arco for espresso at the moment, but want to use it for both if it's not going to lose its original grind setting.

PeterTheGoat
Posts: 37
Joined: 3 years ago

#410: Post by PeterTheGoat »

Yes, I do, but I take into account the backlash:
Any system with a threaded adjuster has backlash (ok, if we forget about ballscrews on cnc machines and anti-backlash nuts).

So let's say I'm grinding espresso at 0-45 setting and pour over at 1-47 setting.
If I am set for espresso and want to change to pour over, I will not just increase the setting to 1-47, but I will first spin the setting ring to 2-something and then reduce the setting to 1-47. This takes out the backlash (the same thing you do when working with a lathe or milling machine - they also have backlash) and guarantees repeatability.
But if I am going from my pour over setting down to my espresso setting, I do not need to overshoot and then readjust, because I was already going down-range and took out the backlash.
So always adjust from a bigger number down, to take out the backlash and get repeatability

This is true for Arco, because with our outside adjusting ring, the inner burr is fixed and the outer burr moves.
The same is true for for example Comandante, but in reverse. They have the outer burr fixed and the inner burr moveable, so you have to adjust in the opposite direction (up-range) to get rid of the backlash. But the theory behind it is just the same.
And the same goes for all big table top grinders. Remember to take backlash into account!

Here is a visual representation of backlash in a threaded connection for those not familiar with the term, it's basically the "play" in the thread (you could not screw something together if there was no play - it would bind):