What is retraction in 3D printing?

Retraction pulls filament back from the nozzle during travel moves to prevent oozing and stringing. Direct drive printers need 0.5-2mm retraction while Bowden tube printers need 3-7mm due to the longer filament path.

Why does PETG string more than PLA?

PETG has a higher viscosity when melted and tends to leave thin strings between travel moves. It benefits from slightly higher retraction distances, lower temperatures and enabling z-hop. Wiping features in your slicer also help.

What is z-hop and when should I use it?

Z-hop lifts the nozzle slightly during travel moves to clear printed features and reduce the chance of the nozzle dragging through stringing. It adds a small amount of print time. Use 0.2-0.4mm for most materials, higher for stringy materials.

How do I tune retraction settings?

Start with the recommended values and print a retraction test tower. Adjust distance in 0.5mm increments and speed in 5mm/s increments. Too much retraction causes clogs and under-extrusion. Too little causes stringing and blobs.

3DPrintCalcs

Retraction Tuning Calculator — Retraction Settings by Material

Calculate retraction distance, speed, travel speed and z-hop settings for your printer type and material.

Printer Type

Select the type

Material

Select the material type

Nozzle Temperature

Hot end nozzle temperature in degrees

Print Speed

Speed of the print head in mm/s

How We Calculate This

This calculator provides starting retraction settings based on your printer type (Bowden or direct drive), material, nozzle temperature and print speed.

How it works

Base values are set per printer/material combination and then adjusted for Bowden tube length, nozzle size and temperature. Bowden setups need significantly more retraction due to the longer filament path and compression in the tube.

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Always verify settings with test prints before committing to final prints.