1Zpresso J-Max

What it does well

Espresso resolution is the headline. 1Zpresso describes it as "the grinder with the finest adjustment among all of the 1Zpresso grinders" when it launched. Home Coffee Expert says the precision "should satisfy even the most perfectionist of espresso lovers."

The grind is even across the range. Home Coffee Expert found it "remarkably consistent across the board at all grind levels," with perhaps slight variation at the very coarsest setting. It rated the build "built to last."

It is quick for a hand grinder. Home Coffee Expert timed a dose at around 30 seconds, slowing at finer settings "but it's by no means slow." The external dial means you never open the grinder to adjust it.

Where it falls short

Changing methods takes work. The dial runs about four and a half rotations, per 1Zpresso's manual. Home Coffee Expert notes this makes "changing between brewing methods slightly more complex."

The finest settings are slower. Home Coffee Expert lists that as its main con, along with needing a stable surface to grind on. It also suggests an electric grinder for anyone without reasonable grip strength.

Reassembly needs care. 1Zpresso's manual walks through a calibration step after every full strip-down. It warns the starting point can vary by about 10 clicks depending on how tightly you set the nut and dial.

Who should buy it, and who shouldn't

Buy a used J-Max if you pull espresso and want very fine control from a hand grinder. It also handles moka pot and AeroPress well, and the settings chart on this page covers each method.

Skip it if you switch between espresso and pour-over every day. All those rotations get tedious. Skip it too if a new grinder with a warranty matters to you, since 1Zpresso no longer sells it.

How it compares

The 1Zpresso J-Ultra is the model 1Zpresso sells now. 1Zpresso states 8 microns per click, and Home Coffee Expert found it lighter and slimmer than the J-Max. See J-Max vs J-Ultra for both dials.

The 1Zpresso X-Ultra uses a 12.5-micron external dial and a smaller burr 1Zpresso pitches at both pour-over and espresso. It is the better pick if filter matters as much as shots.

The KINGrinder K6 costs far less and also adjusts externally, at 16 microns per click per KINGrinder. See J-Max vs K6. The J-Max vs K-Max page covers the other discontinued option.

Owning it

Keep it dry. 1Zpresso's manual says not to wash the grinder with water, and recommends a brush and blower. Our guide to cleaning a hand grinder covers the routine.

Strip it down only as far as the manual allows. The central shaft, burr, burr ring unit and bearings should not be taken apart further. After reassembly, re-zero it; our calibration guide explains why the zero point matters.

1Zpresso still sells J-Max spare parts, from the catch cup to the adjustment dial ring, which helps keep used units running. New grinders carried a one-year limited warranty, which a used unit is unlikely to have.