La Marzocco Linea Mini Review - Page 3

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atao

#21: Post by atao »

Chris, I'm curious how long you waited on this machine for the temp to stabilize when trying different brew temperatures and whether it was different from what you'd do on a full professional machine? The latter part of the question is tangential but i have always been curious how long it takes for a temperature change of a degree or two to take effect on a big machine with a lot of mass.

-Andrew

lagoon

#22: Post by lagoon »

Are the boilers copper, stainless, brass etc?

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contraflow88
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#23: Post by contraflow88 » replying to lagoon »

They are stainless like all the other LM machines.

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HB
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#24: Post by HB »

Yesterday I ran a modified version of the WBC Procedure for Measurement of Brewing Water Temperature. The differences are: (a) it's shorter, (b) allows for no flushing, (c) eliminates the 10 second series, and (d) assumes the portafilter is out for the absolute minimum time (i.e., you are single dosing and dropping the basket in). Below is the approximate timing pattern:
  • Idle for 5+ minutes, pull
  • Wait 4 minutes, pull
  • Wait 1 minute, pull
  • Wait 30 seconds, pull
  • Wait 2 minutes, pull, etc.
And the actual data:
  • 200.6 @ 0:15
  • 202.0 @ 4:35
  • 200.6 @ 6:01
  • 200.2 @ 7:02
  • 199.4 @ 8:02
  • 198.6 @ 8:40
  • 199.1 @ 11:06
  • 199.8 @ 12.44
While it's not very interesting to watch, below is a video showing the above test:
Sorry about the unreadable timer!

My initial interpretation of the data above suggests that the Linea Mini needs 45-60 seconds of recovery time between extractions, otherwise the temperature drops off ~1°F. If we include the outlier @ 4:35, the standard deviation is 1.1. Chris suggested that the Mini's performance might improve with a short flush. That's part of the WBC protocol:
WBC Procedure for the Measurement of Brewing Water Temperature in Espresso Coffee Machines wrote:B) Simulated Dosing and Tamping: The portafilter shall be removed from the machine for approximately 15 seconds. The group shall be flushed with brew water for 2 seconds immediately prior to reinstalling the portafilter to simulate a temperature equalization flush.
In previous tests of prosumer and semi-commercial espresso machines, I've found that allowing a short recovery time after the temperature equalization flush improves consistency, i.e., flush/dose/lock-in instead of dose/flush/lock-in. With that slight modification to the protocol, I ran a similar series with a short 2 second flush, 15 seconds of portafilter out time for simulated dosing/tamping, then pull. Below is the data:
  • 200.7 @ 0.32
  • 200.5 @ 5:09
  • 198.5 @ 7:50
  • 200.0 @ 9:40
  • 199.9 @ 12:53
  • 199.5 @ 17:42
  • 199.5 @ 19:47
That reduced the standard deviation to 0.7, which certainly qualifies as extremely consistent. Below is the video showing my steps:
Dan Kehn

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Teme

#25: Post by Teme »

The data looks quite impressive. Thank you for testing and posting.

Would you happen to also have measured or have a view on the follwing?:

1) Warm-up time from cold?
2) Brew pressure ramp-up vs e.g. a GS3 AV?

Br,
Teme

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malachi (original poster)

#26: Post by malachi (original poster) »

atao wrote:Chris, I'm curious how long you waited on this machine for the temp to stabilize when trying different brew temperatures and whether it was different from what you'd do on a full professional machine? The latter part of the question is tangential but i have always been curious how long it takes for a temperature change of a degree or two to take effect on a big machine with a lot of mass.
This is one of the strengths of this machine.
Changing brew temp on a (larger boiler) commercial machine requires a lot of patience and a lot of water flushing.
On this machine, changing brew temp (as long as the changes are less than about a degree F) works for me as follows:

1 - taste the espresso
2 - change the temp using the dial
3 - flush about 4oz water through machine
4 - go build the shot (takes me about 20s)
5 - flush about 2oz water through machine
6 - pull shot

Note that this assumes I'm not steaming and that the machine was temp stable to start.
Tiny boiler, smart electronics, interesting group design, preheat.

Now... at one point I had to go from Hairbender (198.5f) to a light roasted SO Brazil which is best at about 202f. In that case, I rolled the dial over 6 detents and went away to swap coffees in the grinder. In other words, I made a guess at the rough area that I'd want to have the group at (in terms of brew temp) and got the control in that rough area and then gave the machine about 5 minutes to settle. At that point I flushed about 4oz of water, and then started pulling shots to taste and adjust the temp.
"Taste is the only morality." -- John Ruskin

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malachi (original poster)

#27: Post by malachi (original poster) »

HB wrote:I've found that allowing a short recovery time after the temperature equalization flush improves consistency, i.e., flush/dose/lock-in instead of dose/flush/lock-in. With that slight modification to the protocol, I ran a similar series with a short 2 second flush, 15 seconds of portafilter out time for simulated dosing/tamping, then pull.
This is similar to the protocol I've been running when pulling shots for other people.
I've been going with:

1 - 2s flush
2 - build shot (20s)
3 - pull shot
4 - serve drink
5 - 4s flush/rinse
"Taste is the only morality." -- John Ruskin

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HB
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#28: Post by HB »

Beezer wrote:I feel like I pull good, tasty shots on my current e61 machine, but I'm not sure that something like the Linea would be as forgiving. Is this machine so unforgiving that only experts should apply?
It's only been a couple days, but I'd say it's consistent with the Linea Classic EE and Linea PB that I've used at Counter Culture Coffee over the years. I certainly would not characterize the Linea models as "experts only", but I would agree that they are slightly more likely to channel than an E61 if your barista technique is off. The EP/MP models allow the barista to increase the preinfusion time and thereby increase the forgiveness factor to the same as an E61 (e.g. the La Marzocco GS/3 and Profitec Pro 700 have 4.5 stars for their forgiveness factor).
Teme wrote:Warm-up time from cold?
The steam boiler vacuum breaker closes @ 9 minutes and the steam boiler is pressurized @ 13 minutes. If allowed to warm up with no flushing, the brew group stabilizes in ~40 minutes. In actual use, I flush @ 15 minutes for a few seconds then it's ready 5 minutes later.
Teme wrote:Brew pressure ramp-up vs e.g. a GS3 AV?
The beading time looks about the same as the GS/3 AV video I made years ago:
Before this review wraps up, I'll made another video for the Linea Mini similar to the above.

Note that the Linea Mini preinfusion isn't the same as the GS/3 AV. Instead of pulsing the group solenoid on-off-on, Scott Guglielmino from La Marzocco USA explained that the Mini has a coil of tubing inside the boiler that supplies the preinfusion water prior to full pump pressurization. That's the spritz of water you see exiting from the grouphead during the initial 2 seconds prior to the pump starting.
Dan Kehn

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farmroast

#29: Post by farmroast »

Saabaru and Strega owner, love my old Cremina and miss my old Saab 95 V4 with freewheeling. Never thought I'd be tempted by a pump machine that has a reasonably compact footprint :shock: Thanks Chris and others for a really well done H-B review. And thanks to La Marzocco for thinking about the home barista.
LMWDP #167 "with coffee we create with wine we celebrate"

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Teme

#30: Post by Teme »

HB wrote:The steam boiler vacuum breaker closes @ 9 minutes and the steam boiler is pressurized @ 13 minutes. If allowed to warm up with no flushing, the brew group stabilizes in ~40 minutes. In actual use, I flush @ 15 minutes for a few seconds then it's ready 5 minutes later.
That is pretty quick for the type of machine in question. Not much longer than the Londinium I and quicker than the GS3. With the Londinium I also flush once the boiler has pressurized and let it stabilise for about five minutes after that - around 15 minutes at best.
HB wrote:The beading time looks about the same as the GS/3 AV
This is encouraging. I understand that with the Linea Mini the pre-infusion is built in and cannot be adjusted or opted out for by the user. In the video, would you happen to recall what the pre-infusion settings for the GS3 were in that video?
HB wrote:Note that the Linea Mini preinfusion isn't the same as the GS/3 AV. Instead of pulsing the group solenoid on-off-on, Scott Guglielmino from La Marzocco USA explained that the Mini has a coil of tubing inside the boiler that supplies the preinfusion water prior to full pump pressurization. That's the spritz of water you see exiting from the grouphead during the initial 2 seconds prior to the pump starting.
I was not aware of this. Do I assume correctly that the tubing is within the brew boiler? While not having first hand experience of it, I actually think the way the Linea Mini's pre-infusion works sounds like a sensible approach and possibly preferable to that on the GS3 AV.

I really appreciate the responses as I think this may be sufficient for me to pull the trigger on the Linea Mini. I do like its (relative) no frills approach over the (relative) complexity of the GS3. Simplification was the reason I moved from the GS3 to the Maximatic to the Duetto and then to my current Londinium. As I am considering a move back to a pump-driven machine but want to avoid "too much" complexity, the Linea Mini looks to be a good match for my needs.

Br,
Teme