Phaetus aeCoating™ NexPA-CF25 Filament

Phaetus aeCoating NexPA-CF25 — Co-Extrusion 25% Carbon Fiber PAHT Nylon

A high-temperature carbon-fiber nylon built for stiff, heat-resistant, dimensionally stable functional parts — engineering brackets, jigs and fixtures, RC/drone frames, automotive and tooling components. The base is a high-temp PAHT (PPA-class) nylon reinforced with 25% chopped carbon fiber.

What makes it different: co-extrusion skin-core

Unlike conventional single-extrusion CF nylon, NexPA-CF25 is built with a skin-core structure: the abrasive carbon fiber sits in the core under a pure-resin outer skin. Two practical results — better Z-axis interlayer adhesion (the bond comes from fiber-free resin at the layer boundary), and reduced nozzle wear because less fiber contacts the nozzle wall on the way out. It is still an abrasive filament, but it is engineered to be gentler on hardware than typical CF nylon.

Hardware you need

• Hardened nozzle is mandatory. Carbon fiber is abrasive — a brass nozzle will be destroyed. Use a hardened-steel nozzle at minimum; tungsten carbide is ideal for long runs. Phaetus specs a heater block of at least 12mm to hold temp at speed.
• All-metal hotend rated to 340°C. Print temp is 300-340°C.
• No enclosure required. This grade prints open-frame; a heated chamber is not needed (good ventilation is still recommended — CF nylon can release fumes).

Print settings (from Phaetus TDS)

• Nozzle / print temp: 300-340°C
• Bed: 70-80°C, PEI surface or a coat of PVP (glue stick)
• Nozzle diameter: 0.4-1.0mm
• Print speed: 30-90 mm/s
• Recommended support: S-PAHT quick-remove support

Drying — read this first

Nylon absorbs moisture fast. Load it into a dry box (below 15% RH) the moment you open the vacuum bag. If it has picked up moisture you'll see oozing, popping/bubbles, and rough surfaces — dry at 80-100°C for 4-6 hours to recover. For maximum strength, parts can be annealed at 80-100°C for 4-8 hours and cooled naturally.

Mechanical properties

• Tensile strength (X-Y): 103 MPa  |  Young's modulus: ~8790 MPa
• Bending strength: 170 MPa  |  Bending modulus: ~8570 MPa
• Heat deflection temp: 122.5°C @ 1.8 MPa (187.5°C @ 0.45 MPa)
• Density: 1.23 g/cm³  |  Diameter: 1.75mm

Engineering filament — sold from clearance stock. Store sealed and dry; dry before printing for best results.