Introduction
The UltiMaker 3, S series, and Factor 4 are dual extrusion printers. Using two feeders and two print cores, these UltiMaker 3D printers can use two different materials or two colors of the same material in one print. To ensure good quality prints and a correct alignment, the exact position of both print cores and their offset must be known by the printer.
The print cores have a vertical (Z) and a horizontal (X and Y) offset. The Z offset is determined during build plate leveling. In the active leveling process, this is automatically measured. The X and Y offset is stored via a special calibration process.
Note: The information on this page is about the UltiMaker 3, S series, and Factor 4. To learn more about calibrating the MakerBot Method extruders, please visit this page instead.
When is XY calibration necessary?
The print cores that are supplied with the UltiMaker printers are already calibrated at the factory. For the UltiMaker S3, S5, and S7, one AA 0.4 print core is already placed in print head slot 1. The XY calibration is programmed for the combinations with the other AA 0.4 and the BB 0.4 print core in slot 2. The UltiMaker S6 and S8 ship with two AA+ print cores, which are already installed in the print head and calibrated in these positions. Factor 4 contains two AA cores, which are also pre-calibrated.
When the printer detects a new combination of print cores, the offset should be calibrated. The printer will give a notification on the display when calibration is required.
The XY calibration only has to be done once for each print core combination. After calibration, the printer will store the offset information internally.
Note: The position of the print cores in the print head slots is important. If you swap the same print cores between print head slots 1 and 2, this is seen as a new combination. An XY calibration will be required.
Note: Because the offset information is stored in the printer's memory, this will be reset after a firmware recovery (via micro SD card). Also, all calibrations must be redone after replacing the printer's electronics.
How to perform the XY calibration?
The XY calibration process is programmed on the printer. The printer will notify you when a new XY calibration is necessary, but you can also start the process manually via the menu. For the calibration, ensure you have two print cores installed and two materials loaded. You will also need the XY calibration sheet, which was included in your printer's accessory box.
Tip: If you no longer have the calibration sheet, you can download it here. Print it at 100% scale, or simply use it as a digital reference guide.
The printer will print two grids (one for X and one for Y), after which you must select the best-aligned lines. The whole calibration takes about 10 minutes. Follow the instructions on the printer's display or visit the page linked below for your printer type for detailed instructions.
Note: Not all material combinations work very well for the XY calibration. If possible, always use a fully supported dual material combination. Ideally, use two of the same build material (such as a PLA-PLA or ABS-ABS combination), or a build material with a recommended support material (such as PLA-PVA). Avoid using material combinations with very different temperature requirements, especially for the build plate or build volume, as this may cause adhesion issues or errors.
How does the XY calibration work?
During the calibration process, two grid structures will be printed. The user must select the best-aligned lines with both materials for both X and Y. The best practice is to start looking at the 0 value in the middle of the grid. There will be only one good option.
Note: The XY calibration sheet contains an example picture. This is meant as a reference only and does not reflect an actual result. We are aware of an issue on this sheet that shows multiple well-aligned lines. This can never happen in reality.
Each step of the grid is 73 microns. You can also enter half-step values in the user interface. You might be in doubt between two lines, when both are just not perfect. In this case, you can select the half value in between those for the best result. For example, enter +1.5 if the alignment seems to be between +1 and +2.
The printer will then remember this offset to ensure that the print head is positioned accurately when switching print cores to align the two different colors or materials in dual extrusion prints.
Can I skip the XY calibration?
Yes, you can skip this. An uncalibrated print core combination will not prevent you from printing.
Although the printer will give a notification every time a print job is started with an uncalibrated print core combination, it is possible to ignore this and start the print anyway. Please note that, in dual-extrusion prints, this might lead to print quality issues, such as gaps between or overlaps of the two materials. If this happens, it is recommended to stop the print and run the calibration before reprinting.
Tip: For single extrusion prints, a missing XY calibration will not affect the print quality at all.
For S series and Factor 4: If the currently installed print core combination is not calibrated, this will be shown with a yellow exclamation mark in the 'Printer tasks'.
