User Manual - J-Max Grinder

J-Max grinder
J-Max grinder

Table of Contents

User Instructions

J-Max grinder

Adjusting the grind setting

How to Perform Calibration of 1Zpresso Grinder?
How to Perform Calibration of 1Zpresso Grinder?
  1. 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.
  2. 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.
  3. 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.
  4. Turn the adjustment dial ring clockwise to find the grind setting.
  5. Attach the rubber band to the grinder for a better grip.
  6. Put coffee beans in the hopper and turn the handle clockwise to start grinding.
  7. Follow the guide to calibrate the grinder after disassembling and reassembling the grinder.


Warning: Do not loosen the burr ring unit before step 3.
J-Max grinder
  • Turn the adjustment dial ring clockwise by around two rotations and remove the knurled thumb nut counter-clockwise while pressing the burr.
J-Max grinder
  • Remove the upper bearing cap and upper bearing.
J-Max grinder
  • Remove the burr and central shaftspring and lower bearing cap.
J-Max grinder
  • 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.
J-Max grinder
  • Turn the burr ring unit backward (reverse threads) to the tightest position.
J-Max grinder
  • Align the #0 with the scale mark and the bottom edge of the adjustment dial ring touches the first tier of the scale mark.
J-Max grinder
  • Put the components back in the right sequence: lower bearing cap (the raised edge side facing upward), springshaft and burr.
J-Max grinder
  • 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.
J-Max grinder
  • 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.


Do not attempt to disassemble or remove the following components any further:
J-Max grinder
The central shaft and the burr
J-Max grinder
The burr ring unit
J-Max grinder
The bearings

Video Tutorial


  • Do not clean and wash the grinder with water.
  • Do not wipe your grinder with solvents other than water and alcohol.
  • Keep it 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.
J-Max grinder
Shopping Cart


(For example: JX $129 + Shipping $10 = Total $139)

If YouYou’ll Receive
Cancel before an item is shippedfull refund (item’s price + shipping)
= $139
Return an item in original condition within 7 calendar days from the date you received it100% of the item’s price
= $129
Return an item in original condition over 7 calendar days from the date you received it80% of the item’s price
= 129*0.8 = $103.2

*Any customs duty or relevant charges incurred will be deducted from the refund. (The table above does not include additional charges.)


*A refund request over 7 calendar days from the date you received an item will be refunded partially (80% of the item’s price) and might be denied since the item has been used.



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