1Zpresso – J-Max Grinder
User Instructions
Adjustment
- The grinder is ready to use out of the box. Turn the adjustment dial ring counter-clockwise all the way to the starting point where the resistance starts and the crank handle can’t spin freely. The #0 will be aligned with the scale mark and the bottom edge of the adjustment dial ring will touch the first tier of the scale mark.
- The pyramid-shaped scale mark consists of multiple squares that indicate how many rotations you are at, and it gets smaller while you set coarser settings.
- There are four and a half rotations in total. 90 clicks in a single rotation and each click moves the burr by 0.0088mm/8.8 microns.
- Turn the adjustment dial ring clockwise to find the grind setting:
- Turkish Coffee – 70 clicks
- Espresso – 120 clicks
- Aeropress / Moka-pot – 190 clicks
- Pour-over – 270 clicks
- French press – 360 clicks
Refer to the grind setting tutorial post for different brewing methods.
- Attach the rubber band to the grinder for a better grip.
- Put coffee beans in the hopper and turn the handle clockwise to start grinding.
- Follow the guide to calibrate the grinder after disassembling and reassembling the grinder.
Disassembly
Warning: Do not loosen the burr ring unit before step 3.
- Turn the adjustment dial ring clockwise by around two rotations and remove the knurled thumb nut counter-clockwise while pressing the burr.
- Remove the upper bearing cap and upper bearing.
- Remove the burr and central shaft, spring and lower bearing cap.
- Turn the burr ring unit forward (reverse threads). Disassembling the adjustment dial ring is not suggested.
- Do not clean the grinder with water. Cleaning with a brush and blower is recommended.
Assembly & Calibration
- Turn the burr ring unit backward (reverse threads) to the tightest position.
- Align the #0 with the scale mark and the bottom edge of the adjustment dial ring touches the first tier of the scale mark.
- Put the components back in the right sequence: lower bearing cap (the raised edge side facing upward), spring, shaft and burr.
- Put the upper bearing back from the top.
- While pressing the burr from the bottom, put the upper bearing cap back. The side with concave dots faces upward, and the U-shaped hole fits the shaft properly.
- Tighten the knurled thumb nut to calibrate the grinder while pressing the burr from the bottom.
Note: There are four and a half rotations in total counted from the starting point. The starting point might be different within ±10 clicks due to the strength you tighten the nut and dial.
Warning
Do not disassemble the following components any further:
The Burr and Central Shaft
Burr Ring Unit
Bearings
Precautions
- Do not clean and wash the grinder with water.
- Do not wipe your grinder with solvents other than water and alcohol.
- Keep the grinder in a dry environment in order to extend its lifetime.
- Follow the instructions of re-assembly, ensure to place the components into the correct positions.
- Keep the grinder away from children for safety concerns.
- To prevent the knob from being damaged, putting the grinder and the handle in the case as below picture is suggested.
