When Eureka launches yet another "Mignon" espresso grinder to the market, one is reflexively tempted to answer: "Again?" For by now, more than a dozen espresso grinders in the Mignon family resemble each other in their construction.
But the Eureka Mignon Libra breaks out, at least partially. It is the first Mignon with an integrated scale. The amount of ground coffee is no longer dispensed on a time basis, but rather stops when the target amount is reached in the weighed portafilter. That is brilliant – if it works.
In this test, you will learn how well the Eureka Mignon Libra weighs, grinds, and fits into your routine alongside your home espresso machine. We also provide tips for a good workflow and assess the grinder's strengths and weaknesses.
In the meantime, there is another version of the Eureka Libra, namely the Eureka Libra 65 All Purpose. We have also tested this grinder.
Quick and concise – the essentials 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 set with precision.
- However, the discharge of the ground coffee does not aim perfectly into the portafilter, which means coffee spreads 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 is not possible with the Libra because it would then not complete the weighing grind.
- A dosing ring provides a solution, but it is not included in the package. With a dosing ring, the grinder is a good choice. Without it, it is problematic. Meanwhile, Eureka offers the ring in an additional box (see notice below).
- Suitable dosing rings are available, for example, from Kai from Barista Legends* or also from Wiedemann at Stoll*.
- To tare and thus be able to grind, our Eureka Libra required a minimum weight of 175 grams from the portafilter. Light portafilters and dosing cups therefore partly do not work.
- Continuous grinding without the weighing function is not easily possible. At least 175 grams of weight must still be on the fork for this (triggered via the two cup symbols in the display). Other grinders like the Sette 270 Wi do this better.
- Occasionally, bottomless portafilters do not fit well in the fork.
Buy Eureka Mignon Libra
The following specialty shops* carry the Eureka Mignon Libra and we can recommend purchasing from these retailers.
Switzerland: [Partner links] Adrianos, Simons Kaffee
The modified Eureka Specialità with scale
Strictly speaking, the Eureka Mignon Libra is an Eureka Mignon Specialità with a scale.
Smart is the fact that the grind adjustment of the Eureka Mignon XL is also used, thus improving one of the Specialità's major weaknesses. Otherwise, the Libra is a classic Specialità.
55mm burrs sit in a square aluminum housing. A width of 12.4 cm, height of 43 cm, and depth of 19.2 cm are reminiscent of the Mignon XL.
In other respects, the Libra also demonstrates solid Specialità performance: At 79.8 decibels, it is still relatively quiet. The retention is 2.4 grams. With a grinding speed of 20.2 grams of grinds in 10 seconds, the grinder is in the better middle range of home espresso grinders. The temperature rises from one grind to the next, but at an average of 36.1 degrees Celsius remains in an acceptable range.
When it comes to grind adjustment, there is a bright spot: The Libra is equipped with the larger grind adjustment of the XL. This enables more precise grind setting. Nevertheless, the grinder will never be among the best in its class in terms of adjustment—the larger dial is simply too imprecise for that.
Most importantly: The espresso also tastes like the espresso from an Eureka Mignon Specialità. We get a round, rather body-emphasizing espresso. The Eureka Mignon Libra's grinding mechanism has its strengths more with medium and darker espresso roasts.
Buy Eureka Mignon Libra
The following specialty shops carry the Eureka Libra and we can recommend purchasing from these retailers. All offer the option to adjust the grinder's offset.
Note: These links are so-called affiliate links. If you order via one of these links, you pay nothing extra – however, we receive a small commission, which we invest directly in new test equipment.
We continue to search for competent partners in the DACH region.
A good scale with problems
The Libra's scale works well. It can be calibrated and set with precision. We get minor deviations from the target weight, but this is related to the grinder's calibration. However, the grinder grinds the desired amount of coffee grounds precisely into the portafilter from one extraction to the next.
Unfortunately, there is a problem: While the portafilter has the correct weight, some tenths of a gram are distributed around the grinder. The discharge of the ground coffee does not aim exactly into the portafilter and scatters eagerly all around it.
This is a typical problem with Eureka Mignon grinders, which is prevented on other models by tapping the portafilter during grinding. This approach is not possible with the Libra because it would then not complete the weighing process.
This is not well thought out and is the result of equipping an existing grinder with a scale, but not sufficiently considering further adjustments. An adjustable discharge would be the solution to fill various portafilters cleanly.
Unfortunately, no calibration weight is included. Even with the considerably more expensive Mahlkönig E65s, a calibration weight is not included in the package.
A dosing ring as a solution
A dosing ring provides a solution, but it is not included in the package. Already, the Swiss importer of the grinder pointed out a corresponding solution. Yes, that makes sense. Portafilters can easily be clamped in with a dosing ring and are then ground with precision. 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 offering dosing rings:
Espresso workflow with the Eureka Libra
A grinder with an integrated scale makes many things easier when preparing espresso. 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 tastes good to many coffee drinkers is 1:2.5.
For a double espresso, for example, 15 grams of coffee are ground espresso-fine. At a ratio of 1:2.5, the end result in the cup corresponds to two and a half times that amount, i.e., 37.5 grams.
Classic espresso grinders are first set to the correct grind. Next, the grinding time is determined by grinding repeatedly until the grinder dispenses the exact grind amount. This takes time and uses a lot of coffee.
It is not possible to determine the grinding time before adjusting the grind, since finer and coarser grinds grind for different lengths of time, causing the dose amount to fluctuate.
A grinder with a scale eliminates the need to constantly weigh by hand. After clamping in the portafilter, the grinder tares the portafilter and grinds the exact amount of coffee into it.
Important: When adjusting the grind, approximately 3 grams should still be ground at the new setting and discarded so that the retention is emptied. Only then will the result of the grind adjustment be evident in the next extraction.
We have 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 similarly constructed Eureka Mignon Specialità and thus performs well.
However, consistency and, especially, ease of use 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 ease of use 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 decisively affects the quality of the espresso during preparation. Instead of having to re-weigh 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 preparing espresso and cappuccino at home.
Helpful links:
In Switzerland, the Libra is available, for example, from Quimbaya and from Kaffee-Erlebnis.
Links to Kai's Barista Legends marked with an asterisk are affiliate links to Amazon. You don't pay any more, but we receive a commission if a purchase is made through the link. This supports our work.
SPOILER ALERT: MIGNON LIBRA DOSING FUNNEL IS NOW AVAILABLE 😍😍😍
Dear coffee community and Kaffeemacher followers, in coordination with the Kaffeemacher team, we would like to add this brief 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 fork to ensure the best possible results and avoid losing any coffee when grinding extra large 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 obtain the dosing funnel either already in the Mignon Libra box (upon order as an option) or separately (as an accessory). Please inquire with your retailer of choice.
You will find it in chrome finish, in two possible diameters:
- 58.3 – 57 mm
- 54 – 53 mm (coming soon)
If you would like to discover all the details, we provide you with a "How To Use" video.
By the way, we would like to point out that the Mignon Libra is calibrated from the factory. If, unusually, larger deviations should occur, you have the option to recalibrate the Libra yourself with just a few simple steps. For more information, please contact us here or directly at EUREKA - contact. We are happy to help you.
We thank the Kaffeemacher team for the wonderful review and wish you all a peaceful and joyful Christmas season.
Eureka Team 😊
