Filament Guide

CF Composites Filament Guide

Chopped carbon fiber in any base material. Stiffer, lighter, harder to print.

Last updated: March 2026

CF Composites
Carbon Fiber Reinforced Filaments (-CF)
Chopped carbon fiber in any base material. Stiffer, lighter, harder to print.
Intermediate Popular

Carbon fiber composites are not a single material - they are any base filament (PLA, PETG, ABS, ASA, PA, TPU) blended with short chopped carbon fibers, typically at 10-20% by weight. The fibers dramatically increase stiffness and dimensional stability while reducing weight.[2] Every CF variant inherits the thermal properties of its base material, so PLA-CF still softens at 60°C and PA-CF still needs drying.

The fibers align along the extrusion direction, which means CF parts are anisotropic - much stiffer along print lines than across them. This is useful for designing load-bearing parts but means you need to think about orientation. CF also gives prints a distinctive matte, speckled surface finish that hides layer lines well.[2]

The trade-off is abrasion. Carbon fibers chew through brass nozzles in hours.[1] A hardened steel or ruby-tipped nozzle is mandatory - not optional, not "recommended." Brass will visibly wear within a single spool.

Composition
Base polymer + 10-20% chopped carbon fiber by weight
Print Temp
Same as base material - PLA-CF: 200-230°C, PA-CF: 250-280°C
Nozzle Requirement
Hardened steel minimum. Brass nozzles will be destroyed within one spool.
Stiffness Gain
+30-60% tensile modulus over base material. Most noticeable in PLA-CF and PA-CF.
Weight Reduction
~10-15% lighter than unfilled base. Carbon fiber is less dense than most polymers.
Price Premium
Typically 2-3x the cost of unfilled base material per kg
Pros
  • Major stiffness gains over the base material
  • Reduced warping and shrinkage during printing
  • Excellent dimensional stability
  • Matte surface finish hides layer lines
  • Lighter than unfilled base material
  • Available in many base materials (PLA, PETG, ABS, PA, etc.)
Cons
  • Destroys brass nozzles - hardened steel required
  • More brittle than unfilled base (stiffer but snaps easier)
  • Reduced interlayer adhesion - weaker across layers
  • Anisotropic - strong in one direction only
  • Significantly more expensive
  • Fibers can clog smaller nozzle diameters (<0.4mm)

Best Used For

Drone frames Stiff brackets & mounts RC car chassis Camera gimbals Replacement gears Jigs & fixtures Lightweight enclosures

Niche Tips

Match the base to the job. PLA-CF is great for stiff desk fixtures. PA-CF is the engineering choice for heat and mechanical load. PETG-CF is the middle ground. The carbon fiber adds stiffness to all of them, but thermal and chemical limits remain unchanged from the base polymer.
Use a 0.5mm or 0.6mm nozzle. Fiber clumps can partially clog a 0.4mm nozzle over time, causing underextrusion. A wider nozzle also improves interlayer strength, which is CF's biggest weakness.
Orient for strength. Fibers align along extrusion paths. If a beam needs to resist bending, print it so the longest axis is the X/Y print direction - not the Z layer direction.
PA-CF (Nylon-CF) is the strongest consumer FDM option. Excellent stiffness-to-weight ratio, though FDM layer adhesion still won't match CNC aluminium for critical load-bearing parts. Demands a dry box, all-metal hotend, and careful tuning.

Storage & Humidity

Target: same as base material. PLA-CF follows PLA rules (below 45% RH). PA-CF follows Nylon rules (below 15% RH). The carbon fiber itself is inert - moisture behavior is entirely determined by the polymer matrix.
Drying: Use the drying temperature for the base material. PLA-CF: 45-50°C for 4-6h. PETG-CF: 65°C for 4-6h. PA-CF: 70-80°C for 8-12h.

Bed Adhesion

Best surfaces: Same as the base material. PLA-CF works on any PEI. PA-CF needs glue stick on PEI at 80-100°C. CF filaments generally warp less than their unfilled counterparts, so adhesion is usually easier.
Recommended bed temp: Match the base - PLA-CF: 0-60°C, PETG-CF: 70-85°C, ABS-CF: 100-110°C, PA-CF: 80-100°C.
The reduced warping of CF composites means you can often skip brims and rafts that would be needed with the unfilled base material. Test without first.
← All materials Browse CF filaments on SpoolHound
Related Materials
RELATED
Nylon — base for PA-CF PETG — base for PETG-CF Glass Fiber — less abrasive Nozzle Guide — hardened nozzle required

Recommended Gear

Nozzle Hardened steel nozzle Mandatory for carbon fiber filaments. The abrasive CF particles will destroy a brass nozzle within a single print. Hardened steel or ruby nozzles are the only viable options. CHECK PRICE →
Enclosure 3D printer enclosure Many CF composites use engineering base materials (PA-CF, PC-CF) that require an enclosure. Even PLA-CF benefits from reduced drafts for better layer adhesion. CHECK PRICE →

Frequently Asked Questions

Do I need a hardened nozzle for carbon fiber filament?
Yes, a hardened steel or ruby-tipped nozzle is required. Carbon fiber is extremely abrasive and will destroy a standard brass nozzle within hours of printing, enlarging the bore and degrading print quality. Hardened steel nozzles are affordable and widely available. This applies to all CF composites - PLA-CF, PETG-CF, PA-CF, and others.
Is carbon fiber filament actually strong?
Carbon fiber filament dramatically increases stiffness and dimensional stability compared to the base material, and it reduces warping. However, it does not add much tensile strength and actually makes the material more brittle. CF filament is best for parts that need to be rigid and dimensionally stable, not for impact resistance.
Does carbon fiber filament warp?
CF-reinforced filaments warp significantly less than their base materials. The chopped carbon fibers reduce shrinkage and improve dimensional stability. PLA-CF barely warps at all, and even PA-CF and PC-CF warp less than plain nylon or polycarbonate. This is one of the main reasons CF composites are popular for functional parts.
What base material is best for carbon fiber filament?
PLA-CF is the easiest to print and good for stiff, low-stress parts. PETG-CF adds heat resistance and chemical resistance. PA-CF (nylon-CF) offers the best combination of stiffness, toughness, and heat resistance but requires drying and an enclosure. PC-CF gives the highest temperature resistance but is the hardest to print. Choose based on your mechanical and thermal requirements.

References

  1. Bambu Lab Wiki — Filament Guide. wiki.bambulab.com
  2. All3DP — 3D Printing Materials Guide. all3dp.com