Dual Hot End Calibration (v2)

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Dual Hot End Calibration (v2)



This is the solution for leveling the two nozzles of the JR2x dual hot end (v2). This v2 design includes an adjustment screw for the height of the first (left) nozzle, relative to the second (right) nozzle. The picture below shows the adjustment screw in the top of the hot end. If you do not have the adjustment screw, please review: VIDEO – HD2x/JR2x Dual Hot End Calibration (v1) It is very important to have the nozzle at the same height. If not, this will cause the lower nozzle to hit the part while printing with the higher nozzle.


  • Upgrading to a JR2x dual hot end- Start at #1
  • Purchased the HD2x that comes standard with the JR2x dual hot end- Start at #6


Required Items:


  • JR2x Dual Hot End (HD2x printer comes standard with a JR2x Dual Hot End)
  • 3mm allen wrench (use on the M4 bolt)
  • Glass



1) Start here if installing the head for the first time, proceed to step #6 if the JR2x is already installed.

Turn the printer off and slide the linear bearings so that they are in the right position for the hot end. Make sure that the X bearing is slightly too far left (out of the way)

  • X bearing- moves left and right
  • Y bearing- moves forward and backward

***Picture 1

2) Rotate the Y bearing so that the c-clip is pointing down.

***Picture 2

3) Line the C-Clip up with the slot in the Y bearing holder (pic3). Then snap the hot end on the Y bearing from front to back. Make sure to clamp with your hands, pull up and press down so that the cross rods don’t get bent (pic4). Then verify that the bearing is seated correctly (pic5).

***Picture 3

***Picture 4

***Picture 5

4) Rotate the hot end from left to right so that the X bearing can be slid underneath the hot end (pic6). There is a step on the left side of the hot end in the X bearing holder slot. Make sure to have the bearing fully inside of the bearing housing. Slide the bearing until the left edge of the bearing is directly underneath the adjustment screw. Then clamp the hot end down on the bearing. Make sure to clamp with your hands, pull up and press down so that the cross rods don’t get bent (pic7).

***Picture 6

***Picture 7

5) Set the glass on the heat bed and clip the glass to the heat bed (pic8). By hand, rotate (clockwise) the Z coupling so that the bed raises up to the top (pic9). It should be about 1 inch from the nozzles.

***Picture 8

***Picture 9

6) Nozzle Adjustment: This is the step where the final nozzle adjustment should be done. By hand raise the bed until the glass is just about to touch the lower nozzle. The left nozzle should start out lower than the right nozzle (pic10). There is a large M4 bolt that sticks out of the top of the hot end in the back left (pic11). Screw the bolt (clockwise) to raise the first (left) nozzle. Unscrew the bolt (counterclockwise) to lower the first (left) nozzle. Keep raising and lowering the bed and adjusting the screw. Then run the “First Print- HD2x Calibration” print to verify that the nozzle are aligned properly (pic12).
***Picture 10

***Picture 11

***Picture 12