Back in 2022, when we launched PA11 Carbon Fiber, we didn’t have any enclosed 3D printers with heating strong enough to support materials like pure polyamides. Sure, small parts were printable, but the failure rate was high. Today, however, with fully enclosed printers like Prusa CORE One+, CORE One L, and Prusa Pro HT90, it’s a different story. With higher chamber temperatures, a stable environment and no drafts, it’s possible to print even pure PA11.

That’s why we decided to manufacture Prusament PA11 Natural – without the carbon fiber inside the polymer. Why introduce this version when we already offer the carbon-filled version? Isn’t it just a step back? There’s a clear difference between those two, and it’s all about the mechanical properties of the material. While the PA11 Carbon Fiber offers great high-temperature resistance and dimensional stability, the Pure PA11 offers perfect layer-to-layer adhesion and excellent sliding properties.

What is PA11 and what is it made from?

PA11 (polyamide) is a semicrystalline thermoplastic made from castor oil. It offers high impact resistance (even at low temperatures), great wear resistance, excellent sliding properties and high UV resistance. The material is suitable for various moving parts and bendable components, even for long-lasting outdoor applications.

Gardena hose connector by Brotpeter: an example of outdoor use with high UV and mechanical resistance.

Basic mechanical properties

  • Tensile strength XY: 38.3 MPa
  • Tensile strength XZ: 39.5 MPa
  • Tensile strength anisotropy coefficient: r=0.84
  • Charpy impact resistance (Notched XY): 12.9 kJ/m2
  • Charpy impact resistance (Notched XZ): 11.7 kJ/m2
  • Heat Deflection Temperature (1.8 MPa load): 58.7 °C
  • Heat Deflection Temperature (0.45 MPa load): 122.5 °C

Highest tensile strength anisotropy coefficient

Prusament PA11 Natural offers the highest tensile strength anisotropy coefficient of all Prusaments. This means the material is much harder to break and withstands stress in every direction, no matter the layers’ orientation.

Prusament PA11’s tensile strength anisotropy coefficient reaches r = 0.84 when printed with Prusa CORE One+. The second-highest is Prusament PLA High Speed with r = 0.60. And just for quick comparison, PLA and PC Blend both have r = 0.33, whereas PETG has r = 0.38.

You can learn more about the tensile strength anisotropy coefficient in our PLA High Speed launch article, where we first introduced this number.

This umbrella holder, printed vertically on the build plate, is a good example of how the tensile strength anisotropy coefficient works: the material withstands high forces without breaking between layers. Also, Prusament PA11 offers good UV resistance, making it well-suited for extended outdoor use.

Great sliding properties

Another great benefit of polyamides (in general) is their sliding properties. The polyamide parts offer very low friction on contact. Moving parts can offer great wear performance in suitable applications. This makes PA11 perfectly suitable for printing various gears, for example.

Reduction Gears for Robak 2 by robaki

High chemical resistance

PA11 has good resistance to bases (e.g. NaOH), alcohols (methanol, ethanol), toluene, acetone, motor oil, petrol, diesel, etc. Such resistance is very helpful in making various automotive components, laboratory equipment, and other highly specialized use cases.

High thermal resistance with annealing – up to 122 °C!

In its as-printed state, its heat resistance is limited under load, withstanding only 58.7 °C. During the 3D printing process, the material doesn’t reach the fully crystalline structure and this makes it much less resistant to heat. However, annealing improves this resistance to 122.5 °C when done properly. That’s a 63.8 °C difference! Here’s how to do it properly:

First, you need a proper oven/dryer. We offer a professional Memmert Dryer, but for hobby use, we recommend the Sunlu FilaDryer E2, which is capable of heating up to 110 °C. Second, you need to follow this annealing procedure:

  1. Gradually increase the temperature up to 110 °C at a speed of 1.5 °C/min
  2. Hold the annealing temperature at 110 °C for 6-8 hours
  3. Cool down to room temperature at a rate of 1.5 °C/min

Note that the material may turn slightly yellow after the annealing process.

Colors and Pricing

We are launching Prusament PA11 in one color (Natural), but we have more colors in the pipeline. The natural color of PA11 is translucent yellowish-white with a slight pearlescent look. You can get an 800 g spool for 122 USD (Import duties incl.) / 107 EUR (VAT incl.).

Print preparations and recommended printer equipment

The Prusament PA11 is a hygroscopic material, and we strongly recommend drying before printing, ideally at 90 °C for 6-8 hours to prevent stringing and other print issues. Also, keeping the filament in a dry box significantly slows down the moisture absorption afterwards.

We strongly recommend printing in an enclosure with an active filtration system or placing the printer in a well-ventilated room (see our material safety datasheet). Printing polyamide releases a relatively strong odor into the air and emits potentially hazardous particles (UFP – ultrafine particles). The Prusa CORE One+, CORE One L, and Prusa Pro HT90 are perfectly suitable for this material when equipped with the active filtration system. Also, we offer an enclosure (and advanced filtration for the enclosure) for the MK4S and XL. Higher ambient temperature inside an enclosure also significantly reduces warping.

Print it with the PA Nylon sheet

Printing polyamides on standard PEI print sheets can be challenging due to low adhesion. Small components made from Prusament PA11 Natural may be printed on the satin print sheet with a large brim. However, we strongly recommend using our PA Nylon sheet, which was tailored specifically for polyamides and supports printing large models without extra preparations.

Our PA Nylon print sheet comes with a matte texture similar to the satin print sheet and works perfectly with PA11. For successful printing of small components, you only need to wash the print sheet with water before every use. This will ensure easy print removal and a long sheet lifespan. However, the adhesion may be too high when printing large and mostly solid components. For such models, we recommend applying a very thin layer of glue stick on the print surface as a separation layer.

Do NOT wash the sheet with Acetone, IPA (isopropyl alcohol), or other alcohol-based chemicals (including window cleaner, 3DLAC, etc.). Using IPA (and other chemicals) makes the surface matte and changes its structure and adhesion. This leads to a shorter lifespan and a much higher risk of damaging the sheet. Visible grease stains on the print surface (fingerprints, for example) can be cleaned with water and dish soap. Also, we recommend washing the sheet with dish soap before turning it over.

You can learn more about the PA Nylon Sheet in our announcement article.

And that’s it! Do you like our old, yet new PA11? Let us know in the comments. We can’t wait to see your new and amazing creations.

Happy printing!