The information in this article applies to the UltiMaker S6, S8, Factor 4, and Factor 4 Plus.
Introduction
The Z motor is responsible for moving the build plate (Z stage) up and down during printing. Its long lead screw makes very small steps, lowering the build plate by fractions of a millimeter. This vertical motion is what allows each new layer to be added at exactly the right height.
As with all machined parts, the pitch of the lead screw could have imperfections, although imperceptible. For accurate motion, and therefore accurate Z heights of printed parts, the lead screw is calibrated at the factory. The firmware of the UltiMaker S6, S8, and Factor Series printers allows for this scaling offset value to be put into the menu. This value is then used to correct for any scaling imperfections, enabling you to print accurate parts, each and every print.
Please note that the Z spindle scaling factor is not a Z offset value. It corrects for pitch imperfections, and is specific to each Z motor. This value is not related to and does not affect the distance between the nozzle and the build plate.
Note: Although the older S series printers (S3, S5, and S7) as well as previous UltiMaker models (UltiMaker 2 and 3 series) use the same motor types, the firmware does not include this scaling offset feature.
When to perform this calibration?
The scaling offset value is calibrated for each Z motor at UltiMaker's manufacturing facilities. The corresponding value is entered into the firmware. Under normal circumstances, this does not need to be reprogrammed by the printer's user. The value also does not get reset after a firmware update or factory reset*.
Only when replacing certain hardware components must the Z spindle value be re-entered. This affects the Z motor itself (each has a different value) and the electronics (which store the value). After replacing either of these parts, reset the Z spindle scaling factor.
Note: UltiMaker S6 and S8 firmware 11.1.0 had a bug affecting this calibration, where it could take up to 10 minutes for the calibration value to be stored correctly. This has now been resolved.
Note: If you are prompted to enter the calibration value when setting up your new printer (during the welcome setup), please contact UltiMaker Support and see the instructions below.
Where to find the scale value?
Each Z motor is already calibrated at UltiMaker's factory, using special equipment. This is done for the motors built into the printers and Z motors available as spare parts. This is where to find the correct scale values:
- Factor Series: The Z spindle scale value for the original Z motor is on the back panel of the Factor Series printer, visible after removing the back cover panel. (see left image)
- S6 and S8: The Z spindle scale value for the original Z motor is on the motor itself. This can be accessed by placing the printer on its side and removing the bottom cover. (see right image)
- Replacement motors: For a replacement Z motor, the new calibration value is included with the motor.
How to enter the Z spindle scale?
When prompted, find the Z scale option in the printer's menu. In the Options menu (gear icon), go to Maintenance → Frame & motion → Calibrate Z spindle scale.
The scaling factor is an 8-digit value, starting with '1' or '0' and 7 decimals. Enter all 8 digits in the menu and press confirm to store the information.
Need further support?
If you have any questions about this process or when you experience any issues with entering the scaling factor, please contact UltiMaker Support. Share your printer type, serial number, and any relevant images for efficient assistance.
