Carbon-fibre, glow-in-the-dark, wood-fill, glitter PLA — the filaments that make the coolest prints are also the ones quietly destroying your nozzle. If you print composites through a standard brass nozzle, here is what is happening and how to fix it.
Why brass nozzles wear out
Brass is soft. It prints beautifully and conducts heat well, which is why it ships as standard. But abrasive fillers — carbon fibre, metal powder, wood particles, glow additives — scrape the inside of the nozzle like sandpaper. Within a spool or two, the bore widens, the tip rounds off, and print quality collapses.
The signs of a worn nozzle
- First layers that used to stick now lift.
- Dimensions drift; extrusion width becomes inconsistent.
- Under-extrusion and rough surfaces that no amount of tuning fixes.
The fix: hardened steel
A hardened-steel nozzle resists abrasion many times longer than brass. You trade a little thermal conductivity (print 5–10 °C hotter to compensate) for a nozzle that survives spool after spool of composite filament.
When to go further
Printing composites daily? Look at tungsten-carbide or ruby-tipped nozzles for near-permanent wear resistance. For most makers, hardened steel is the sweet spot.
Match your nozzle to your filament: shop hardened-steel and high-flow nozzles, and pair them with specialty & composite filaments.