Eureka Mignon Libra Coffee Grinder

The Libra grinds by weight, not by time: it stops when the dose you set is in the portafilter, with an accuracy of ±0.2 g. Pick the single or the double dose and set the grams with − and +, a tenth of a gram at a time (hold the button and the value scrolls). You can switch from single to double even while it is grinding.

If + and − are no longer on the display, it is almost always because they were held down together by mistake: this locks the doses and the two buttons go dark. To bring them back, hold them down together again. You can also do it on purpose, so the doses cannot be changed by accident.

The Libra weighs the coffee straight into the portafilter, so it has to detect the portafilter on the fork before it starts. "FH" appears if the portafilter is not seated properly or if you press the dose button more than 10 seconds after placing it: take the portafilter off, put it back and press single or double dose straight away.

If it stops while grinding, a knock on the portafilter or the fork has paused it: press a dose button within 5 seconds to finish the dose. It also stops by itself when the scale sees no increase in grams, for example with an empty hopper, to protect the motor.

Turn the dial clockwise for a finer grind, anticlockwise for a coarser one. The adjustment is stepless: go gradually and grind a little coffee every 2 notches at most.

When you go finer, do it with the motor running, while it grinds a dose. The Libra's motor is designed for home use and is less powerful than a professional grinder's: if you turn the dial a full turn with the motor stopped, the grinder can jam. If it happens, write to us before sending it for repair.

No: the first calibration is done and tested in the factory, so the Libra is ready to use. Recalibration is only needed if the weighing loses accuracy.

In that case, when switching on hold + and single dose for about 7 seconds. Put the empty portafilter on the fork (the display suggests a 20 g sample weight, which you can change with − and +), press double dose to take the tare, place an object of exactly that weight in the portafilter and finish by holding + and single dose for a few seconds.

They weigh the same way: same weighing technology, same display, same ±0.2 g accuracy. The burrs are different, and so is what each one is for.

• Libra: 55 mm hardened steel flat burrs, made for espresso, with dark roasts.
• Libra 65 All Purpose: 65 mm flat burrs with a blind upper burr, without holes, which cuts retention even further. The All Purpose design works for espresso and every kind of filter, with light roasts. It has the King Size dial with rev counter, handy for switching between methods, and its fork holds both the portafilter and the filter cup.

In short: espresso only, the Libra; espresso and filter, the Libra 65 All Purpose.

The one that matches the mains in your home. The 220 V version is for 220-240 V mains, the voltage in most of the world, Europe included; the 110 V version is for low-voltage mains, such as North America.

If you are not sure about your mains, write to us before ordering.