Chopped Fiber Infusion Printing

Chopped fiber infusion printing deposits fiber-filled thermoplastics to create stronger, stiffer 3D printed parts with improved temperature resistance and good geometric freedom at low volumes.

Overview

Chopped fiber infusion printing builds parts layer-by-layer using thermoplastic materials pre-loaded or infused with short carbon, glass, or aramid fibers. The process runs much like FDM, but the chopped fibers increase stiffness, strength, and heat resistance compared to unfilled polymers, while keeping print speeds and setup effort reasonable.

Use this when you need functional, load-bearing prototypes or low-volume production parts that would otherwise be machined from aluminum or standard engineering plastics. Expect good strength in-plane, moderate improvement through the Z-axis, and a matte, fiber-textured surface that may need secondary finishing on critical interfaces. Tolerances are similar to industrial FDM: fine enough for brackets, housings, jigs, and end-of-arm tooling, but not for precision bearing fits without post-machining. Tradeoffs: lower mechanical performance than continuous fiber reinforcement, some anisotropy, limited material palette compared to commodity FDM, and higher material cost per kilogram than standard filament.

Common Materials

  • Nylon 6 carbon fiber filled
  • Nylon 12 carbon fiber filled
  • Nylon glass fiber filled
  • PETG carbon fiber filled
  • PEEK carbon fiber filled
  • PEKK carbon fiber filled

Tolerances

±0.005" to ±0.010"

Applications

  • Robotic end effectors and grippers
  • Assembly and inspection jigs and fixtures
  • Lightweight structural brackets and mounts
  • Drone and UAV frames and arms
  • Sensor and electronics housings under moderate load
  • Replacement machine guards and covers

When to Choose Chopped Fiber Infusion Printing

Choose chopped fiber infusion printing for low- to medium-volume parts that need higher stiffness and heat resistance than standard FDM, without the cost and complexity of metal. It fits best for functional prototypes, fixtures, and production parts with moderate loads, where design freedom and short lead times matter more than maximum possible strength.

vs Continuous Fiber FDM

Pick chopped fiber infusion printing when you need stronger-than-standard plastic parts but don’t require the very high directional strength of continuous fibers. It simplifies design because you don’t need to plan fiber paths, gives more uniform properties, and usually prints faster and cheaper for general-purpose brackets, fixtures, and housings.

vs Standard FDM 3D printing

Choose chopped fiber infusion printing when standard FDM materials are too flexible, creep too much, or lack heat resistance. It delivers stiffer parts with better dimensional stability under load, making it suitable for functional fixtures, load-bearing brackets, and end-use components rather than just form-and-fit prototypes.

vs SLS nylon 3D printing

Use chopped fiber infusion printing when you want higher stiffness and better high-temperature performance than unfilled SLS nylon, and your geometry works with FDM-style support and anisotropy. It can be more cost-effective for single large parts or fixtures, and offers easier material handling and machine access for small shops.

vs CNC machining

Select chopped fiber infusion printing when geometry is complex, lightly loaded, or would be expensive to machine from aluminum or engineering plastic. You’ll trade some surface finish and tolerances for lower setup cost, internal features that are impossible to machine, and rapid iteration on design changes.

vs Injection molding

Use chopped fiber infusion printing for composite parts in prototyping or low production volumes where mold cost isn’t justified. It lets you evaluate fiber-reinforced designs, tune geometry, and bridge to tooling, accepting higher unit cost but negligible upfront investment and very fast design changes.

Design Considerations

  • Keep minimum wall thicknesses ≥1.5–2.0 mm and avoid tall, thin walls aligned with the Z-axis to reduce warping and layer cracking.
  • Orient parts so main load paths lie in the XY plane and add generous fillets at load introductions to reduce stress concentrations in the printed layers.
  • Cap small holes and precision bores as printed pilots and leave machining allowance if you need tight fits or bearing seats.
  • Limit unsupported overhangs to typical FDM rules (≈45°) and design self-supporting features or split large parts for easier printing and assembly.
  • Call out only truly critical tolerances and surfaces; leave non-critical faces as-printed to avoid unnecessary post-processing cost.
  • Provide clear material specifications (base polymer and fiber type/content) and expected load cases so the shop can choose orientation and print parameters appropriately.