Prusament PA11: The Filament That Doesn't Care Which Way You Print It

Every FDM print has a weak axis — the layer lines that separate under stress in one direction even when the part looks solid from every angle. Prusament’s new PA11 Natural is built specifically to not have one.

Why This Category Matters

Anisotropy — the tendency of 3D-printed parts to be strong along the print layers but weaker between them — is the reason gears strip, snap-fit parts crack, and load-bearing brackets fail along a layer line instead of across the material itself. PLA and PETG, the two most common desktop filaments, have anisotropy coefficients of 0.33 and 0.38 respectively, meaning their between-layer strength is roughly a third of their in-plane strength. For parts under real mechanical stress — gears, hinges, reduction systems — that gap is exactly where failures happen.

What Makes It Different

PA11 Natural, a castor-oil-derived nylon, posts an anisotropy coefficient of 0.84 — the highest of any Prusament material — meaning it holds close to full strength regardless of which direction the load hits relative to the print layers. In practice: tensile strength of 38.3 MPa in the XY plane and 39.5 MPa in XZ, with notched Charpy impact resistance of 12.9 and 11.7 kJ/m² across the same axes. Those XY/XZ numbers landing within a point of each other is the whole story — most filaments show a much bigger split.

That strength profile comes at the cost of PA11 Carbon Fiber’s better high-temperature dimensional stability — PA11 Natural’s heat deflection temperature is 58.7°C as-printed, rising to 122.5°C only after a deliberate annealing cycle (heating to 110°C at 1.5°C/min, holding 6-8 hours, then cooling at the same rate). The material also resists bases, alcohols, toluene, acetone, motor oil, petrol, diesel, and UV exposure, which is why Prusa is positioning it for automotive and outdoor components alongside gears and moving mechanisms.

The Catch / Who It’s For

PA11 Natural isn’t a drop-in filament swap. It requires an enclosed printer with active chamber temperature control — Prusa specifies its CORE One+, CORE One L, and Pro HT90 — plus active filtration, since printing polyamide emits ultrafine particles the company flags as a real air-quality concern, not a formality. Drying before printing (90°C for 6-8 hours) and a dedicated PA Nylon print sheet are both required, and common cleaning solvents like isopropyl alcohol and window cleaner will damage the print surface rather than clean it. At $122 for an 800g spool, it’s priced well above commodity PLA or PETG, and it currently ships in one color: a translucent, pearlescent natural finish.

Source: Prusa3D Blog

Content created with AI assistance and reviewed for accuracy.