Glossary · Part

3D printing

Nozzle

The small metal tip from which the molten plastic emerges. Its opening determines how finely you can print.

Explained in more detail

The nozzle sits at the end of the hotend. The standard is 0.4 mm. 0.2 mm allows finer details with a much longer print time, while 0.6 and 0.8 mm increase throughput and strength. Rules of thumb: line width about 100 to 120 % of the nozzle diameter, layer height at most about 75 to 80 %. Brass nozzles conduct heat well but wear quickly with abrasive filaments containing carbon or glass fibres. Nozzles made of hardened steel, with a ruby tip or made of tungsten carbide are available for these.

Where does the term come from?

The English word nozzle is a diminutive of nose, so it literally means something like "little nose": a narrowed opening from which something emerges.

In practice

• On screw-in nozzles the diameter is usually stamped on, for example "0.4", so you can tell nozzles apart even after removing them.
• After switching to a different size, you must select the matching nozzle profile in the slicer, otherwise it calculates with the old line width.
• Check the nozzle roughly every 200 to 300 print hours in normal use. Widened, out-of-round openings and uneven lines show wear.
• For fibre-reinforced filaments, manufacturers usually recommend at least 0.4 mm, often 0.6 mm, because small nozzles clog with them.
• Tighten screw-in nozzles at operating temperature and hold the heater block steady. Too much force can tear off the nozzle or heatbreak.

Not to be confused

The nozzle is only the tip, not the whole hotend. With quick-change systems, however, you often swap nozzle and hotend together as one module.

Frequently asked questions

Which nozzle size is best?

For most prints 0.4 mm. 0.2 mm is worthwhile for miniatures and fine text, and a 0.6 mm nozzle prints many objects in about half the time.

How often does the nozzle need replacing?

There is no fixed interval. With PLA and PETG a brass nozzle lasts a long time, with abrasive filaments it wears quickly. Replace it when the opening is visibly widened or the lines become uneven despite suitable settings.