Project Dashboard Maintenance and Repairs Z-axis Offset Adjustment for the LulzBot Mini Workflow

1 Getting Started

Follow the steps in this tutorial to adjust the Z-axis offset on your LulzBot Mini. The height of the Z-axis offset influences print results, as the thickness level of the first layer is a crucial aspect to any print. This tutorial will help you adjust the thickness level of the first layer, improving print quality in the process.

Lulzbot Mini 3D Printer

2 Z-offset Explained

Before beginning the tutorial, it's important to understand some context around how the Z-axis influences print quality.

  • When auto-leveling, the nozzle touching the washers determines the 0 position on the Z-axis.

  • This means the bed is actually slightly below washers, thus Z offset: -1.35 means the printer will start the first layer 1.35 mm below the top of the corner washers (the 0 position in the Z-axis).

  • Due to a few different factors, including filament used, print bed treatments, and other modifications, the thickness of the first layer may need to be adjusted.

Ideal first layer thickness
Squished first layer needing Z offset calibration
Z offset too high above the bed, needs calibration

3 Items Required

(1) LulzBot Mini Desktop 3D Printer

(1) USB cable, included with your LulzBot Mini

(1) GNU/Linux, Mac OS X, or Windows-based computer

Items Required

4 Open Control Window in Cura

4A
Verify your LulzBot Mini is plugged into computer with power off.

4B
Power on printer.

4C
Load test model into Cura.

4D
Open control window.

Load test model
Open control window

5 Enter G-code Instructions

5A
M851 -> Reports current Z offset in millimeters

5B
Note: Before printing, be sure to make small adjustments to avoid damage to the nozzle or bed.
Example: M851 ZXXX -> Adjusts Z offset to "XXX" mm

M851 Z-1.1 -> Adjusts Z offset to 1.1 mm

5C
M500-> Save setting change

Retrieve Z offset
Adjusts Z offset by "XXX" mm

6 Example of Z offset adjustment

  • The first layer of the print is more squished than we'd like
  • After entering an M851 command, the Z offset shows as -1.35
  • A M851 Z-1.25 command will start the print slightly higher and make the print slightly thicker
  • A M500 command will save the new Z offset setting

Note: A few tests may be necessary to dial in the best Z offset for your printer

Overly squished first layer
Ideal first layer thickness
Done! Take me home