Skip to content

AON-M2 Machine Calibration


The information on this page is for firmware version 18.08 and newer. If you are unsure of what firmware version you are using, please verify that you are using version 18.07 or newer with the command M115 before proceeding. To update firmware, see this guide.

Before proceeding with the Z offset calibration, ensure you have probed the bed and made the initial coarse adjustments.

Z Offset Calibration

After you have probed the bed and done a rough calibration using the M290 command, the distance from the nozzle to the bed will be nearly calibrated, but not as precise as required for printing perfect first layers. This must be fine-tuned by printing a first layer and making further adjustments to get the initial spacing correct.

The offset value that is modified in this process is stored in the machine memory, so once the calibration has been completed, only small adjustments should have to be made when printing at different temperatures (to compensate for thermal expansion) or when changes to the machine have been made (such as changing nozzles, repairing tools, or swapping build surfaces).

Calibration Using Samples

We provide two calibration G-code files, as well as their corresponding factory files for you to use. Each file will simply print a small square in the center of the build plate, giving you time to make small adjustments using M290. You will need to run this process for both toolheads to ensure the offsets are correct on both tools.

File Description Usage
t0_z-calibration.gcode Left Tool Calibration Use with ABS for T0
t1_z-calibration.gcode Right Tool Calibration Use with ABS for T1
z-calibration.factory Base Factory File Modify to suit your needs and material choice

A typical process would be as follows:

  1. Load filament for the tools (we recommend using ABS for calibration)
  2. Clean and secure the print bed.
  3. Preheat both the chamber, and the bed to the desired temperature for printing your parts.
  4. Run the bed probing procedure once temperatures are stable.
  5. Coarsely adjust the nozzle-to-bed distance.
  6. Start the t0_z-calibration.gcode print job.
  7. While the first layer is printing and extruding, adjust the tool height further using small increments such as M290 Z-0.05.
  8. Once you are satisfied with the print distance, you may stop the print and repeat the process for T1 using it's respective calibration file.


In the terminal page of the user interface, you can use the up and down arrows on your keyboard to quickly cycle through past commands.

Calibration Using Skirts and Brims

While the initial calibration will bring the nozzle-bed distance close to it's ideal, you will still need to manually fine tune the offsets on each print while extruding a sacrificial skirt or brim for the first layer. Once calibrated, this should only require very small changes (e.g. M290 Z0.05) to account for small changes in machine dimensions that accompany changes in machine temperature due to thermal expansion.