Nozzle

Theory

The nozzle is the final exit point for molten filament. Standard nozzles are 0.4 mm diameter brass: the industry default balancing detail and print speed. Smaller nozzles (0.2-0.25 mm) produce finer detail but require slower speeds and clog more easily. Larger nozzles (0.6-1.0 mm) print faster with higher layer heights but with lower resolution. Hardened steel nozzles are required for abrasive filaments (CF, GF); brass nozzles wear within hours. Ruby or tungsten carbide nozzles last indefinitely with any filament.

Application

Use 0.4 mm brass for standard PLA/PETG work. Switch to 0.6-0.8 mm for large structural parts and engineering filaments for speed. Use 0.2-0.25 mm for miniatures and fine text. Always use hardened steel or higher for abrasive filaments. When changing nozzle diameter, update the slicer nozzle size setting, extrusion width, and first-layer calibration.

Common mistakes

Brass nozzles with carbon-fibre filament wear out within 50-100 g of filament: the nozzle orifice becomes oval and extrusion quality degrades. Cold pulls (atomic pulls) are the best first-line method to clear soft jams before resorting to a needle. Running any nozzle above its rated temperature causes thermal degradation of coatings and increased wear. Never swap nozzles cold: always heat to print temperature first.

Related terms: Hotend, Extrusion Width, Flow Rate