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Z Motor

The Z motor is a stepper motor that moves the hotbed along the Z-axis using a Z-axis synchronous belt. It includes a motor cable and a drive pulley.

When to Use This Guide

• The Z motor is burned out and cannot move.
• техническая поддержка have analyzed the logs and confirmed that the fault lies with the Z motor.

Required Tools and Materials

1. H2.0 Hex wrench
2. H1.5 Hex Wrench
3. New Z motor

Safety Warning

IMPORTANT!

Always power off and disconnect power on the printer before performing maintenance work. Not doing so means there is a risk of electric shock, short circuit, and damage to the printer or surrounding area.

When a maintenance task necessitates the printer being powered on, use insulated gloves for safety and pay special care not to pinch, damage, or put pressure on any exposed wires, connectors, or circuit boards. Additionally, the nozzle can be extremely hot so never touch it with exposed skin.

If you have or the steps in this guide, please

Removing the Z-Motor

Step 1: Clean the Printer Base

Clean any foreign debris from the printer base, especially residue on the polished rod, and remove the printer’s glass cover.

Step 2: Lock the Heatbed

1. Case where the motor can still operate:

Using the display, lower the heatbed to the bottom. Then, use a 2.0 mm hex wrench to tighten the three screws and lock the three sliders, just as you did when first unpacking the heated bed. Finally, turn off the printer and unplug the power cord.

2. Case where the motor fails to operate entirely

Turn off the printer and unplug the power cord. Tilt the printer, manually move the Z-axis belt to lower the heated bed to the bottom, and lock the three sliders with three screws.

Locking the heated bed is a crucial preparatory step. This process secures the relative positions of the three Z-axis screws, preventing them from rotating or shifting unexpectedly due to external forces or the weight of the bed when the belts are released. It preserves the bed’s reference plane, prevents excessive tilting, and ensures the initial levelness of the build platform.

Step 3: Remove the Rear Panel

You can refer to this wiki to remove the printer rear panel: Replacing the P2S Rear Panel Bambu Lab Wiki.

Step 4: Disconnect the Motor Wires

1. Locate the MC board on the right side at the back of the printer, and disconnect the Z motor cable from the bottom of the MC board.

2. Remove the Z motor cables from the cable clips one by one.

3. Peel off the tape and remove the Z motor cable.

Step 5: Release the Tension Spring and Tensioner Pulley

1. Lay the printer on its side.

If you need to turn the printer upside down, make sure to remove the display screen first to prevent damage! For information on how to remove the display screen, see: Replacing the Screen Bambu Lab Wiki.

2. Release the spring, then loosen the black screw using a 2.0 mm Hex wrench.

Step 6: Remove the Z-Motor

1. Use a 2.0 mm Hex wrench to remove the four screws. These screws are secured with high locking torque, so it is recommended to use a sturdy tool to avoid stripping the threads. When removing the last screw, support the motor with your hand to prevent it from falling.

2. Remove the Z motor from the printer at a slight angle.

Installing the Z-Motor

Step 1: Install the Z-Motor

1. Install the Z motor into the printer at a slight angle, with the motor cable facing outward (refer to the figure below for guidance).

Gently push the motor into place, then loop the Z belt onto the motor’s drive pulley.

2. Tighten the four screws using a diagonal tightening pattern.

Step 2: Lock the Spring and the Tensioner

Snap the long arm of the spring into position, then secure the tensioner pulley with its screw.

Step 3: Remove the Slider Locking Screws and Check the Movement

1. Place the printer upright and remove the locking screws from the three sliders.

2. Then tilt the printer and move the Z-axis belt back and forth to confirm that the heated bed moves smoothly up and down.

Step 4: Thread the Motor Cables

Reapply the tape to the cables, then route the motor cables through the snap-in slots on the base and secure them to the side cable clips, just as they were before removal.

Step 6: Install the Rear Panel

You can refer to this wiki article to reinstall the printer rear panel: Replacing the P2S rear panel Bambu Lab Wiki.

Verifying Functionality

Connect the power cord and start the printer. Use the screen to control the heatbed and check whether it moves up and down normally. If it operates correctly, the Z motor has been successfully replaced.