Before you choose
- Filler percentage alone does not rank finished parts.
- Check nozzle wear and feed-path requirements.
- Compare direction, conditioning and any required annealing.
Start with the base polymer and the job
PA-CF, PETG-CF and PPS-CF have different base polymers and formulations. Reinforcement can change stiffness, dimensional behavior, surface and elongation. Choose a grade around the part requirement rather than treating all carbon-filled filament as one material.
Prepare the hardware
Confirm nozzle material, bore and any manufacturer restrictions. Abrasive fillers can wear components and change the extrusion geometry over time. Worn equipment can affect repeatability even when a previously successful slicer profile is unchanged.
Control moisture and post-treatment
Filled nylon still needs the appropriate moisture-management process. Dry-state and conditioned data can differ. Some grades require an annealing step for their published performance; that step needs dimensional checks and a controlled procedure.
| Review item | What to ask |
|---|---|
| Formulation | Base polymer, grade code and stated filler content |
| Print setup | Nozzle requirements, diameter and approved profile |
| Conditioning | Drying, storage and specimen moisture state |
| Performance | Orientation, test method and post-treatment |
| Maintenance | Nozzle inspection and replacement criteria |
Trial the interfaces as well as the material
Threads, contact surfaces, small holes and thin flexing features can respond differently to a filled grade. Test the actual geometry. In a fixture, consider where a replaceable bushing or contact pad is more suitable than relying on the printed surface alone.
Questions buyers ask
Is chopped-CF filament the same as continuous-fiber printing?
They use different reinforcement arrangements and processes. Do not transfer a continuous-fiber part’s properties to a chopped-filled filament.
Does more filler always mean better performance?
Filler content is one formulation variable. Dispersion, base polymer, processing and the property you need also matter.
Sources
- Prusa — fiber-filled composites
Abrasive reinforcement and hardware requirements; use grade-specific settings.
- Polymaker — Fiberon PA6-CF20 guidance
A grade example distinguishing drying, annealing and subsequent conditioning.