Cafelat Robot User Experience - Page 113

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jpender
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#1121: Post by jpender »

tv79 wrote:On another note, I'm finding it rather difficult to exceed 4-5 bar without feeling like I'm forcing the arms downward to an unsafe degree. IIRC Paul recommends 6-7 bar as a good starting point. So I'm wondering if I should ignore my instincts and push further, or stick with 4-ish bar?
If you like how the coffee tastes... But otherwise you might try a different position. Further out on the arms you'll get more leverage. And it's easier to push down from above than pull from below.

I usually start at around 8 bar and either keep it there or let it slowly drop to 6-7 bar. I think the Robot can take it. But it does require some effort. The first week I used my Robot I was just slightly sore in a spot in my upper arms/shoulders area. I plan to eventually modify my Robot arms so that I can generate leverage more easily.

jpender
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#1122: Post by jpender »

Geert wrote:I demonstrated that when you don't pour directly on the screen you don't have a crater. When doing so you'll also notice the water stays clear.
I've been playing around with this for the last week, alternating between pouring onto one spot on the screen (with a standard non-gooseneck kettle) and using an aluminum foil disk to shield the screen from the pour:



What I've found is that the vast majority of the time the initial beads of coffee during the pre-infusion are asymmetric when I pour as usual, favoring the spot (or close to it). The puck usually has some sort of very shallow cavity there. When I use the foil disk the pre-infusion beads very evenly. And the water is almost perfectly clean too. So it's making some sort of difference.

Is it tasting differently? If so, it is too subtle to discern. So maybe it doesn't matter. But all else being equal a nice symmetric pre-infusion at least sounds desirable. Is it meaningless? I don't know. But putting a piece of foil in there (I leave it in during the shot) has almost zero effect on my workflow.

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Balthazar_B
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#1123: Post by Balthazar_B »

John, since you're targeting the center post, have you found any optimally-angled funnels that will do the same thing?
- John

LMWDP # 577

thirdcrackfourthwave
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#1124: Post by thirdcrackfourthwave »

tv79 wrote:. . . .On another note, I'm finding it rather difficult to exceed 4-5 bar without feeling like I'm forcing the arms downward to an unsafe degree. IIRC Paul recommends 6-7 bar as a good starting point. So I'm wondering if I should ignore my instincts and push further, or stick with 4-ish bar?

For context, I'm using a 15g dose, Lavazza Super Crema (normally Counter Culture Hologram but I'm currently on an Italian roast kick after returning from Italy :), and Aergrind.
Push further. The difference between the 4-ish and the 6-8ish Mr. Pratt recommends is significant. The recommended range produces a much better shot. I'm always in the 'range.' Further, while not recommended Mr. Pratt says that he has gone to 14 bar (I think) so the 'unsafe' would not relate to catastrophic failure by the machine. Blowing out your triceps might be a different story. :D

tv79
Posts: 237
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#1125: Post by tv79 »

Balthazar_B wrote:On the Robot, I normally dose 15-16g and shoot for normales in 30-35 sec, not including preinfusion. And I tend to favor roasts in the medium to medium-dark range.
Ah, ok..around 30 sec was what I was figuring. Forgot to mention earlier, but I also typically brew normales as well. That said, as I was experimenting earlier, I ended up going a bit further and was very pleased with the result. Unfortunately I was more focused on the pressure gauge and didn't use my scale at the time, so I'm not sure how much actually ended up in the cup.
jpender wrote:If you like how the coffee tastes... But otherwise you might try a different position. Further out on the arms you'll get more leverage. And it's easier to push down from above than pull from below.

I usually start at around 8 bar and either keep it there or let it slowly drop to 6-7 bar. I think the Robot can take it. But it does require some effort. The first week I used my Robot I was just slightly sore in a spot in my upper arms/shoulders area. I plan to eventually modify my Robot arms so that I can generate leverage more easily.
I think part of my being hesitant is because I'm coming from the Flair, where I was always super cautious not to push too hard. Sounds like the Robot may be more robust so this isn't as much of a concern. I'm pushing on the flat part of the arms closest to the end, so I can certainly apply more force, just didn't want to break anything. :lol:

tv79
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#1126: Post by tv79 »

thirdcrackfourthwave wrote:Push further. The difference between the 4-ish and the 6-8ish Mr. Pratt recommends is significant. The recommended range produces a much better shot. I'm always in the 'range.' Further, while not recommended Mr. Pratt says that he has gone to 14 bar (I think) so the 'unsafe' would not relate to catastrophic failure by the machine. Blowing out your triceps might be a different story. :D
Hehe ok that makes me feel a lot better. I have absolutely no plans to ever hit 14 bar!

I'll shoot for at least 6 bars tomorrow. The 4-5 bar range is just where I notice it becomes more difficult to push the arms further. But again, sounds like this is more of an issue with the Flair than the Robot.

jpender
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#1127: Post by jpender »

Balthazar_B wrote:John, since you're targeting the center post, have you found any optimally-angled funnels that will do the same thing?
Are you talking to me? I don't understand the question. I'm not targeting the center post. My kettle doesn't pour that focused a stream of water.

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Balthazar_B
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#1128: Post by Balthazar_B replying to jpender »

I meant where you want the water to flow onto the screen so as to avoid a stream onto the perforations. It looks like your foil directs it to the center post on the screen, or am I not seeing the photo correctly?
- John

LMWDP # 577

jpender
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#1129: Post by jpender »

I don't know where it directs it but my guess is mostly to the outside edge. My thought was to prevent the water from mixing turbulently with the puck, which the foil mostly does. The water is either completely clear or slightly gold colored but still fully transparent. When I pour without the foil the water is brown and there's noticeable sediment on top after the shot.

I could probably try simply pouring more gently without the foil or even distributing the pour around the screen. But as I said, I'm not really sure if it matters or not. Is an asymmetric pre-infusion a problem?

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yakster
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#1130: Post by yakster »

My kettle pours with a fine, focused steam and the water remains clear when I target the post.

I suppose one could put a hat over the post to pour onto, a sort of landing pad, and remove it before pulling the shot. A funnel that tapers and has said hat on the end to sit on the post would be easier to remove and possibly interesting, especially to those without gooseneck pouring kettles.
-Chris

LMWDP # 272

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