

Eureka Mignon Libra review: it’s a tough one
Eureka gives its classic some integrated scales with the launch of the Mignon Libra. This espresso grinder measures coffee to the exact decimal place. It’s tremendous but not tidy.
I parted with my coffee grinder a while ago. My Eureka Mignon Specialita has been replaced by a Baratza Sette 270wi. The Baratza is both ugly and noisy. But it does boast in-built scales. The plastic part serves its purpose perfectly in that the grinder delivers precisely 18.3 grammes of ground coffee – i.e. the amount I set it to. I’d like to replace this device with a quieter, nicer grinder, but as yet I can’t find anything like it – or at least not in the price segment under 1,000 francs.
Enter Eureka, which provides exactly what I want in the form of the Mignon Libra: a grinder based on the classic Mignon design with an integrated set of scales. I want to know if it’s worth switching, so I ordered a test device from the supplier.

New vs old: almost everything is the same
As with every Mignon, the Libra uses the same 55 mm disc grinder as the Specialita. You can adjust the grind using a stepless wheel on top of the device. Personally, I find it a little on the small side. If you’ve got a 3D printer, you can easily solve the problem. There are a number of different hacks to help you install a larger wheel.

Source: Simon Balissat
What’s new about the Libra is that I can now insert a portafilter. This sits on a support, which can be adjusted to different sizes. As a result, I can also get a bulky portafilter, such a La Marzocco, to fit well into the grinder. It’s important for it to be secure, as the coffee is ground straight into the portafilter.

Source: Simon Balissat
Sometimes it’s totally off the mark
You can then use the display to set the desired amount of coffee for an espresso or a doppio in grammes – but only in grammes. In previous versions, the duration of the grinding process determined how much ground coffee ended up in the portafilter. In this version of the Libra, Eureka no longer offers this option at all, which actually makes sense.
In fact, getting coffee by weight is much more accurate than setting the grinding time. That’s because a grinder is always subject to a certain amount of variability. 10 seconds sometimes gives you 17 grammes, while other times you’ll get 18 grammes. The Libra always delivers exactly the weight that I set on the grinder.

Source: Simon Balissat
Once the portafilter is firmly inserted, I press the button for espresso or doppio and the grinder does the rest. It stands to reason that I shouldn’t touch the portafilter during the grinding process, otherwise I’d interfere with the scales. The grinding itself is super, but unfortunately, about a gramme of coffee ends up next to the portafilter. It’s annoying and shouldn’t happen. This is remedied by a special funnel attachment, which luckily enough, I’d already bought anyway. That way, no more bits go astray.

Source: Simon Balissat
Quiet and precise
I’m very satisfied with the Libra’s performance, but I didn’t expect anything less. Eureka has been making high-quality coffee grinders for years, and this is no exception. The disc grinder delivers consistent results as standard and the grinder is quiet. The scales also work perfectly. If I don’t quite get the 18 grammes I set, the grinder carries on for a fraction of a second until the full 18 grammes is there.
To check, I reweighed the coffee grounds each time with a different set of scales and noticed that 18.2 grammes ended up in the portafilter when it was set to 18 grammes. However, this is constant over a number of times. At just under 80 decibels, the Libra isn’t exactly super-silent, but it’s not comparable with the nearly 90-decibel Baratza Sette rumble that I’m met with every morning. The latter is about as loud as a hand-held grinder and harmful to hearing (site in German) in the long term.

Source: Simon Balissat
What the grinder can’t do
The Libra is clearly an espresso grinder. It also works with just an affixed portafilter. I tried to grind coffee into a mug, but this doesn’t work and the machine displays an error message. On rare occasions, I get the error message even if there’s a portafilter correctly attached. When that happens, I have to briefly remove and reinsert the portafilter each time.
If you want flexibility, you’re better off with the Baratza Sette, as it’s also equipped for making other types of coffee, such as filter or bialetti. In other words, you don’t necessarily have to grind directly into the portafilter. It even comes with an extra container just for this.
Verdict
The Libra does what it promises. It’s a Eureka Mignon with integrated scales. If you’re looking for a grinder to use exclusively with a portafilter then it’s definitely worth the extra cost over the classic Mignon. The reason being you simply have more control and can always be sure that the same amount of coffee comes out of the grinder. I’ve deducted points because the lack of funnel attachment means a lot of ground coffee ends up next to the portafilter. It’s also a shame that I need to affix a portafilter in order to use the scale rather than just being able to opt for a cup. Nonetheless, I’m seriously toying with the idea of replacing my Baratza Sette with the Libra, as I only need it for espressos. Additionally, I’d like a nicer and, above all, quieter grinder.
Header image: Simon BalissatWhen I flew the family nest over 15 years ago, I suddenly had to cook for myself. But it wasn’t long until this necessity became a virtue. Today, rattling those pots and pans is a fundamental part of my life. I’m a true foodie and devour everything from junk food to star-awarded cuisine. Literally. I eat way too fast.