Print Speed

Theory

Print speed directly affects print quality, time, and material output. At higher speeds the hotend must melt filament faster: if the melt rate cannot keep up, under-extrusion occurs. The maximum volumetric flow rate of the hotend sets a hard physical limit on print speed for a given nozzle diameter and layer height. Corner speeds must also be considered: abrupt direction changes at high speed cause ringing (ghosting) artefacts due to frame vibration. Modern input shaping (Klipper's resonance compensation) mitigates ringing.

Application

Set outer wall speed to 40-60 mm/s for quality, infill to 80-150 mm/s for speed. Keep first layer speed at 20-30 mm/s for adhesion. Enable per-feature speed control: bridges at 25-40 mm/s, overhangs at 25-40 mm/s. Use acceleration tuning and jerk settings to soften speed transitions. On Bambu printers use dynamic speed and flow compensation profiles.

Common mistakes

Printing too fast with a stock 0.4 mm nozzle above 150 mm/s almost always causes under-extrusion in standard hotends. Ringing artefacts at sharp corners indicate insufficient acceleration tuning: do not simply reduce speed without calibrating acceleration. Speed inconsistency across feature types (e.g. fast infill into slow perimeter) causes pressure transients that appear as blobs at the infill/perimeter boundary.

Related terms: Flow Rate, Retraction, Part Cooling