When Eureka launches yet another "Mignon" espresso grinder, do I reflexively want to respond: "again"? Because by now, more than a dozen espresso grinders in the Mignon family are structurally similar.
But the Eureka Mignon Libra at least partially breaks out of this pattern. It's the first Mignon with an integrated scale. The output quantity of ground coffee is no longer time-controlled, but instead stops when the target amount is reached in the weighed portafilter. That's genius when it works.
In this test, you'll learn how well the Eureka Mignon Libra weighs, grinds, and fits into the workflow next to your home espresso machine. We also provide tips for a smooth workflow and assess the grinder's strengths and weaknesses.
In the meantime, there's another version of the Eureka Libra, namely the Eureka Libra 65 All Purpose. We've tested this grinder as well.
Quick Summary - The Most Important Facts About the Eureka Mignon Libra in 2 Minutes
The Eureka Mignon Libra is a good espresso grinder. It builds on the strengths of the Eureka Mignon series, combines them, and is improved by the scale.
- The Libra's scale works well. It can be calibrated and adjusted precisely.
- However, the discharge of ground coffee doesn't aim perfectly into the portafilter, which means coffee scatters around the grinder during grinding.
- This is a typical problem with Eureka Mignon grinders, which is prevented on other models by tapping the portafilter during grinding.
- This approach isn't possible with the Libra because it then can't complete the weighing grind.
- A dosing ring can help, but it's not included in the box. With a dosing ring, the grinder is a good choice. Without one, it's problematic. By now, Eureka includes the ring in an accessory box. See also Eureka's message to us at the very bottom of the page.
- Unfortunately, the dosing ring is not included in the package. That's weak. However, you can get it from, for example, Kai from Barista Legends*, also available in wood on Etsy* or from Wiedemann at Stoll*.
- To tare and thus be able to grind, our Eureka Libra required a minimum weight of 175 grams on the portafilter. Therefore, lightweight portafilters and dosing cups don't work in some cases.
- Continuous grinding without the weighing function is not easily possible. At least 175 grams of weight must still be on the holder. This contradicts the logic. This type of grinding is triggered by pressing the two cup indicators on the display. Other grinders like the Sette 270 Wi do this better.
- Bottomless portafilters sometimes don't hold well in the holder.
The Rebuilt Eureka Specialità with Scale
Strictly speaking, the Eureka Mignon Libra is an Eureka Mignon Specialità with a scale.
Smart is that the grind adjustment of the Eureka Mignon XL is also used, thus improving one of the Specialità's main weaknesses. Otherwise, the Libra is a classic Specialità.
55mm burrs sit in a square aluminum housing. 12.4 cm width, 43 cm height and a depth of 19.2 cm are reminiscent of the Mignon XL.
And in other respects, the Libra also demonstrates solid Specialità performance. At 79.8 decibels, it's still relatively quiet. The retention is 2.4 grams. With a grinding speed of 20.2 grams in 10 seconds, the grinder is in the better mid-range of home espresso grinders. The temperature rises from grind to grind, but at an average of 36.1 degrees Celsius remains in the acceptable range.
The grind adjustment settings are a bright spot, because the Libra is equipped with the larger grind adjustment wheel of the XL. This allows for more precise grind adjustment. Nevertheless, the grinder will never rank among the best in this regard, because the larger wheel is also too imprecise.
Most importantly: the espresso also tastes like the espresso from an Eureka Mignon Specialità. We get a rounded, body-forward espresso. Here, the grinding mechanism of the Eureka Mignon Libra shows its strengths especially with medium and darker espresso roasts.
Buy Eureka Libra
The following specialty retailers carry the Eureka Libra and we can recommend purchasing from these businesses. They all offer the option to adjust the machine's offset.
Germany:
Austria:
We search for specialist partners whose work and service quality we know and trust, and we're in close communication with the retailers mentioned. The links are affiliate links. If you order through one of these links, you won't pay a cent more – but we'll receive a small commission that we invest directly in new test equipment.
We continue to search for competent partners in the DACH region for you.
A Good Scale with Problems
The Libra's scale works well. It can be calibrated and adjusted precisely. We see slight deviations from the target weight, but that's related to the grinder's calibration. However, the grinder precisely grinds the desired amount of ground coffee into the portafilter from shot to shot.
Unfortunately, there's a problem. While the portafilter shows the correct weight, some tenths of a gram are scattered around the grinder. The discharge of ground coffee doesn't aim precisely into the portafilter and scatters eagerly around it.
This is a typical problem with Eureka Mignon grinders, which is prevented on other models by tapping the portafilter during grinding. However, this approach isn't possible with the Libra because it can't then complete the weighing process.
This is not fully developed and is the result of retrofitting an existing grinder with a scale, while further adjustments weren't sufficiently considered. An adjustable discharge would be the solution to fill different portafilters cleanly.
Unfortunately, no calibration weight is included. However, the much more expensive Mahlkönig E65s also doesn't include a calibration weight in its package.
A Dosing Ring as a Solution
A dosing ring can help, though it's not included in the box. Even the Swiss importer of the grinder pointed to a suitable solution. Yes, that makes sense. Portafilters can easily be clamped in with the dosing ring and are then ground precisely. With a dosing ring, we observed no scattering around the grinder.
The version with a dosing ring is a good workaround for a technical weakness of the Eureka Mignon Libra.
Possible shops that offer dosing rings:
Espresso Workflow with the Eureka Libra
A grinder with an integrated scale makes espresso preparation much easier. Espresso is a short, strong coffee drink with a coffee-to-water ratio typically of 1:1.5 to 1:3. A popular ratio that many coffee drinkers enjoy is 1:2.5.
For a double espresso, for example, 15 grams of coffee are ground espresso-fine. The final result in the cup, at a ratio of 1:2.5, corresponds to two and a half times the amount, so 37.5 grams.
Classic espresso grinders are first adjusted to the correct grind setting. Then the grinding time is determined by grinding repeatedly until the grinder outputs the exact amount. This takes time and uses a lot of coffee.
It's not possible to determine the grinding time before adjusting the grind setting, because finer and coarser grinds take different amounts of time to grind, so the dose amount varies.
A grinder with a scale eliminates the need for constant manual weighing. After clamping the portafilter, the grinder tares the portafilter and grinds the exact amount of coffee into it.
Important: when adjusting the grind setting, about 3 grams should still be ground through at the new setting and not used, to clear the retention. Only then will the effect of the grind adjustment be apparent in the next extraction.
We've written an article here about adjusting specialty espresso.
Conclusion on the Eureka Mignon Libra
Without a dosing ring, the Eureka Mignon Libra is not a fully developed grinder. It performs in the basic categories at the level of the structurally similar Eureka Mignon Specialità and thus performs well.
However, consistency and especially usability are limited to poor due to the scattering of ground coffee around the portafilter.
With the use of a dosing ring, consistency becomes very good and usability becomes good. In this combination, the Eureka Mignon is a very good scale grinder that provides a helpful simplification of espresso preparation for home baristas.
The ratio of water to coffee significantly influences the quality of espresso during preparation. Instead of having to reweigh with an external scale, the home barista can now rely on the grinder.
With a dosing ring, the Eureka Mignon Libra is a very good espresso grinder for making espresso and cappuccino at home.
Helpful Links:
In Switzerland, the Libra is available, for example, at Quimbaya and at Kaffee-Erlebnis.
Links marked with an asterisk to Kai's Barista Legends are affiliate links to Amazon. You won't pay more, but we receive a commission if a purchase is made through the link. This supports our work.
Update January 20, 2023: Eureka has sent us the following message.
SPOILER ALERT: MIGNON LIBRA DOSING FUNNEL IS NOW AVAILABLE 😍😍😍
Dear Coffee Community and Kaffeemacher followers, in consultation with Kaffeemacher, we would like to add this short comment to provide you with complete information on the correct use of the Mignon Libra. In this context, we would like to emphasize that our research and development department has developed a dosing funnel specifically designed for the Mignon Libra holder to ensure the best possible results while preventing coffee loss when grinding larger quantities. We recommend using this accessory for:
- > 8 grams for single shot
- > 15 grams for double shot
- 20 - 22 grams for triple shot
You can get the dosing funnel either already in the Mignon Libra box (upon request as an option) or separately (as an accessory). Please check with your retailer of choice.
It's available in chrome finish, in two possible diameters:
- 58.3 - 57 mm
- 54 - 53 mm (coming soon)
If you'd like to discover all the details, we provide you with a "How To Use" video.
By the way, we'd like to point out that the Mignon Libra is pre-calibrated from the factory. If, unusually, larger deviations should occur, you have the option of recalibrating the Libra yourself in just a few simple steps. For further information, please contact us here or directly at EUREKA - contact. We're happy to support you.
We thank Kaffeemacher at this point for the great review and wish you all a peaceful and joyful holiday season.
Eureka Team 😊
