KEY TAKEAWAYS
- Z Hop is a slicer setting that lifts the printhead or lowers the build plate before non-printing movements.
- It helps prevent nozzle crashes and reduces imperfections on prints.
- Setting it up in slicers like Cura and PrusaSlicer is straightforward.
Cura’s Z Hop, also known as Z Lift in PrusaSlicer, is a slicer setting that lifts the printhead or lowers the build plate slightly before a travel move. This small “hop” prevents your nozzle from hitting the printed model and knocking it off the build plate. It also helps reduce some surface imperfections like stringing.
What is Z Hop
Z Hop is a feature in Ultimaker’s Cura slicing software that helps you avoid issues where the printer’s nozzle might knock over parts of your print.
When Z Hop is enabled, the nozzle moves up along the Z-axis during a travel move, creating a gap between the nozzle and the print. This “hop” prevents the nozzle from colliding with the top layer of your print and knocking it off the build plate.
On 3D printers where the nozzle is locked in the Z-axis, the hopping motion can also be accomplished by lowering the build plate slightly.
You can adjust the Z Hop height to fit your specific needs. For example, in Cura, you have the option to control how high the nozzle lifts. Setting the right height can make a big difference in print quality.
Z Hop is especially useful for prints with lots of details or tall, thin parts. Enabling Z hop adds a bit of time to the printing process, but the safety of knowing your print won’t get knocked over is worth it.
Why Enable Z Hop
We already know that Z-Hop prevents your print head from colliding with your object. This small move prevents the nozzle from hitting the printed layer when the printhead travels across the build plate.
But there are a couple of other reasons for enabling Z hop.
If your printer is producing stringing or blobs, Z-Hop reduces the unwanted disposition of filament on the print’s exterior. Lifting the nozzle keeps it clear of the printed object, preventing unwanted filament from building on the print surface.
Another benefit is that Z Hop prevents your nozzle from scratching the top layers of your print. Scratches generally occur on prints with a large top surface area. As the nozzle moves across previously printed sections, it can drag across the surface.
Z hop completely eliminates scratches by moving the print head clear of the print during travel movements.
Setting Up Z Hop in Cura
Z Hop Height determines how much the nozzle lifts during travel moves. The default value in Cura is 0.2 mm, which is perfect for most prints. But you can adjust it if needed. Just note that higher values result in longer print times as the printer requires more time to raise and lower the extruder.
Z Hop Speed is another important factor. It controls how fast the nozzle moves up. A standard setting is around 10 mm/s. Keeping it low is best to avoid rapid movements that can vibrate your print.
You might also see an option called Z Hop Only Over Printed Parts. This limits Z Hop to areas where prints already exist. Enabling this setting is useful for avoiding unnecessary Z movements while still getting the benefits of Z Hop.
Here’s how to set up Z Hop in Cura:
- To set up Z Hop in Cura, go to the Print Settings tab and select “Show Custom” to access advanced options.
- Click the three lines icon and turn on “All” settings. Scroll down to the Travel section. Here, you’ll find the Z Hop When Retracted option. Check this box.
- Once selected, related settings will pop up. You can adjust Z Hop Height, Z Hop Speed, and Z Hop Only Over Printed Parts.
With these changes, your printer will lift the nozzle during specific movements. This reduces the risk of printing errors and improves the quality of your 3D models.
Related Settings
When you use Z Hop in your 3D printing, you can combine several other settings to get better print results.
One related setting is Combing. Combing keeps the printhead within the boundaries of the object when traveling between different parts of the print. This helps prevent stringing and makes your prints look cleaner.
Another useful setting is Coasting. Coasting stops the extrusion a bit before the end of a line to relieve pressure in the nozzle. This prevents issues caused by over-extrusion and improves the surface quality of your prints.
Combining and coasting work well with Z Hop to further enhance the quality of your prints.
