Nylon (PA) printing: moisture control, chamber choices, annealing and CF-PA
Short answer
Nylon's main problem is water. Prusa says badly stored polyamide can absorb water up to 10% of its weight, and Polymaker's CoPA data sheet shows XY tensile strength falling from 78.0 MPa dry to 34.3 MPa wet [1, 6]. Dry it before printing (80–100 °C for 4–12 hours, depending on the maker) and print from a sealed or heated dry box [2, 8]. Carbon-fiber PA needs a hardened nozzle [2].
Published ranges at a glance
The span of values that makers publish for 12 products (PA (nylon)) in the filament database, by grade. Every product, with its source, is listed in the full table below the guide.
| Grade | Products | Nozzle °C | Bed °C | Drying °C | HDT at 0.45 MPa, °C |
|---|---|---|---|---|---|
| PA-CF | 7 from 6 brands | 260–320 | 40–120 | 70–100 | 84.5–215 |
| PA (nylon) | 5 from 5 brands | 245–300 | 25–110 | 80–110 | 58.7–119 |
Why moisture matters more for nylon
Prusa’s drying article contrasts PLA, which changes little when it takes up humidity, with polyamide, which is affected quite significantly [12]. Its polyamide article says improperly stored polyamide can absorb water weighing up to 10% of the filament, and that moist PA forms bubbles, uneven layers and a poor surface [1].
The data sheets show what that water does to finished parts. Polymaker tested PolyMide CoPA (a nylon 6 / nylon 6,6 copolymer) dry and after 48 hours in 60 °C water, at an average moisture content of 6.16%:
| CoPA property | Dry | Wet |
|---|---|---|
| Tensile strength (XY) | 78.0 MPa | 34.3 MPa |
| Young’s modulus (XY) | 2703 MPa | 724 MPa |
| Notched Charpy impact (XY) | 6.9 kJ/m² | 27.7 kJ/m² |
Source: [6].
Wet nylon is weaker and much less stiff, but tougher. Bambu Lab reports a similar loss for carbon-fiber PA6: flexural strength drops from 151 MPa dry to 95 MPa humid, and flexural modulus from 5460 to 3560 MPa, while PET-CF barely changes (131 to 127 MPa) [3].
Grades differ in how fast they take up water. Prusament PA11 lists 0.26% after 24 hours and 0.46% after 7 days at 25 °C and 30% humidity [9]. Bambu PAHT-CF lists a saturated water absorption of 0.88% at 25 °C and 55% RH [4].
Drying and printing from a dry box
| Product or source | Drying setting |
|---|---|
| Prusa Knowledge Base, polyamide in general | at least 4 h, below 90 °C |
| Prusament PA11 Carbon Fiber | 90 °C, 6 h |
| Bambu Lab Wiki, PA and PA-CF (oven) | 80 °C, 8–12 h |
| Bambu PAHT-CF | 80 °C, 8–12 h |
| Polymaker PolyMide CoPA | 100 °C, 8 h |
| Polymaker Fiberon PA6-CF20 | 100 °C, 10 h |
Drying is only half the job. Polymaker’s CoPA and PA6-CF20 data sheets say to store and use the filament below 20% relative humidity, and its wiki says to keep nylon in a heated filament dryer for the entire print [6, 8]. Bambu Lab marks a desiccant as required during printing for PA [2]. Prusa recommends keeping PA11 Carbon Fiber in a dry box between uses, or drying it before each print [12]. The drying planner and the drying chart collect the values by product.
Polymaker’s audible test is useful: if extrusion makes popping or cracking noises, the filament needs drying [8]. See wet filament for the other symptoms.
Bed, plate and chamber: two schools
The manufacturers split into two approaches, and the right one depends on the grade.
Hot bed, warm chamber. Prusa’s general polyamide article recommends a 285 °C nozzle, a 110 °C bed and its PA Nylon sheet, and says an enclosure helps a lot because warping is pure polyamide’s main problem [1]. Prusament PA11 specifies 275 ± 10 °C, a 100 ± 10 °C bed and a 55 ± 5 °C chamber [9]. Bambu Lab recommends an enclosed printer for PA and lists 100–120 °C on its Engineering, Smooth PEI and Textured PEI plates [2]; its PAHT-CF data sheet adds a 45–60 °C chamber [4].
Cool bed, open door. Polymaker’s CoPA data sheet lists a 25–50 °C bed [6]. Its wiki says not to set the bed above 50 °C and to keep chamber doors open, because a bed or air temperature above 50 °C risks warping, and repeats this for its PA-CF grades [8]. The CoPA data sheet still lists the enclosure as needed at ambient temperature, which suggests an enclosure for shelter rather than for added heat [6].
Fiber content changes the picture. Prusa says carbon-filled polyamides warp far less and can be printed without an enclosure [1]. Follow the data sheet of the exact spool rather than a generic nylon profile.
Annealing and moisture conditioning
Bambu Lab classes PA as crystalline: annealing raises crystallinity and can improve strength, stiffness, heat resistance and water resistance, but parts may warp and become less tough [13]. The published schedules vary widely:
- Polymaker CoPA: 80 °C for 6 hours [6].
- Polymaker Fiberon PA6-CF20: 100 °C for 16 hours [7].
- Bambu PAHT-CF: 80–130 °C for 6–12 hours [4].
The effect can be large. Prusament PA11 lists a heat deflection temperature of 58.7 °C at 0.45 MPa as printed, while its product page gives up to 122.5 °C after annealing [9, 10].
Annealing also dries the part. Polymaker says annealed nylon then needs moisture conditioning, which happens on its own as the part absorbs water from the air, or faster after 48 hours in a humid environment [8]. The CoPA table above shows the direction of that change: more moisture means lower stiffness and higher impact strength.
Nozzles and carbon-fiber PA
For unfilled nylon, the makers disagree on the nozzle. Prusament lists a standard 0.4 mm brass nozzle for PA11 [10]. Polymaker says brass abrasion happens quite often with unfilled CoPA and highly recommends a wear-resistant nozzle [6].
For carbon- or glass-filled nylon there is no disagreement. Bambu Lab requires a hardened steel nozzle for PA-CF/GF and recommends 0.6 mm [2]; its PAHT-CF data sheet lists 0.6 mm as recommended [4]. Polymaker estimates a brass nozzle lasts about 9 hours with Fiberon PA6-CF20 [7], and Prusa calls a hardened nozzle necessary for PA11 Carbon Fiber [11].
The fiber also lifts heat resistance sharply. Heat deflection at 0.45 MPa is 192 °C for Prusament PA11 Carbon Fiber against 58.7 °C for unfilled PA11, and 194 °C for Bambu PAHT-CF [11, 9, 4]. The carbon-fiber guide covers nozzle sizes and abrasion, and the heat resistance comparison lists the values by product.
Fumes
Safety: Prusa says polyamides emit a strong odor with potentially dangerous ultrafine particles, so a well-ventilated room or an enclosure is a must [1]. Prusa describes its Advanced Filtration System as a HEPA filter plus activated carbon and names nylon among the materials that release more particles and odor [14]. Bambu Lab’s PAHT-CF page asks for a well-ventilated area or an air filtration or exhaust system [5].
All 12 products in the database
| Source | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Bambu Lab | PAHT-CF | PA-CF | 260–290 | 80–100 | 1.06 | 80 °C, 8–12 h | 194 °C @ 0.45 MPa 170 °C @ 1.8 MPa | not published | [4] |
| Elegoo | PAHT-CF | PA-CF | 260–290 | 90–110 | 1.08 | 75–85 °C, 8 h | 194 °C @ 0.45 MPa | not published | [15] |
| eSUN | PA-CF | PA-CF | 260–300 | 45–60 | 1.24 | 70 °C, ≥ 12 h | 155 °C @ 0.45 MPa | not published | [16] |
| Overture | Easy Nylon | PA (nylon) | 245–260 | 50 | 1.12 | 95 °C, 7 h | not published | not published | [17, 18] |
| Polymaker | PolyMide CoPA | PA (nylon) | 250–270 | 25–50 | 1.12 | 100 °C, 8 h | 111 °C @ 0.45 MPa 70 °C @ 1.8 MPa | not published | [6] |
| Polymaker | Fiberon PA6-CF20 | PA-CF | 280–300 | 40–50 | 1.17 | 100 °C, 10 h | 215 °C @ 0.45 MPa 173 °C @ 1.8 MPa | not published | [7] |
| Prusament | PA11 Carbon Fiber | PA-CF | 280–290 | 100–120 | 1.11 | 90 °C, 6 h | 192 °C @ 0.45 MPa 152 °C @ 1.8 MPa | not published | [11, 12] |
| Prusament | PA11 | PA (nylon) | 265–285 | 90–110 | 1.02 | not published | 58.7 °C @ 0.45 MPa 49.9 °C @ 1.8 MPa | 10 | [9] |
| Siraya Tech | Fibreheart PPA | PA (nylon) | 280–300 | 70–80 | 1.21 | 80–100 °C, 4–6 h | 81 °C @ 0.45 MPa 73.5 °C @ 1.8 MPa | not published | [19] |
| Siraya Tech | Fibreheart PPA-CF | PA-CF | 280–320 | 70–90 | 1.20 | 100 °C, 4–6 h | 84.5 °C @ 0.45 MPa 82.5 °C @ 1.8 MPa | 12 | [20] |
| Siraya Tech | Fibreheart PPA-CF Core | PA-CF | 280–320 | 80 | 1.23 | 80–100 °C, 4–6 h | 97 °C @ 0.45 MPa 84 °C @ 1.8 MPa | not published | [21] |
| Sunlu | Easy PA | PA (nylon) | 250–280 | 30–50 | 1.10 | 80–110 °C, 4–12 h | 119 °C @ 0.45 MPa | not published | [22, 23] |
Questions
Why do nylon supports fuse to the part?
Moisture. Polymaker says nylon supports printed in the same material should be removed before they absorb much moisture, or they can bond permanently [6]. Bambu Lab recommends removing PAHT-CF supports within 2 hours and drying the model if they stick [5].
Can nylon be printed without an enclosure?
It depends on the grade. Prusa says carbon-filled polyamides warp much less and can be printed without an enclosure, and Polymaker tells you to keep the chamber doors open for CoPA and its PA-CF grades [1, 8]. Bambu Lab recommends an enclosed printer for all PA grades, and Prusament PA11 needs a 55 °C chamber [2, 9].
Sources
- Polyamide (Nylon). Prusa Knowledge Base. Manufacturer documentation. Up to 10% water uptake, drying below 90 °C for 4 h, warping, enclosure, UFP emissions. Accessed October 12, 2026.
- Filament guide: printer, nozzle, AMS, build plate, glue compatibility and required parameters. Bambu Lab Wiki. Manufacturer documentation. PA drying, plate temperatures, enclosed printer, hardened nozzle for PA-CF/GF, AMS notes. Accessed October 12, 2026.
- PET-CF / PPA-CF / PPS-CF / PA6 CF Carbon Fibers Filament Usage Guide. Bambu Lab Wiki. Manufacturer documentation. Dry vs humid flexural strength and modulus of PA6-CF and other CF grades. Accessed October 12, 2026.
- Bambu PAHT-CF Technical Data Sheet (V3.0). Bambu Lab. Technical data sheet. Settings, 0.6 mm nozzle recommended, chamber 45–60 °C, HDT, water absorption, annealing range. Accessed October 12, 2026.
- PAHT-CF product page. Bambu Lab. Product page. Support removal within 2 hours, enclosure requirement, ventilation. Accessed October 12, 2026.
- PolyMide CoPA Technical Data Sheet (V5.4). Polymaker. Technical data sheet. Dry vs wet mechanical data, drying, annealing 80 °C 6 h, wear-resistant nozzle note. Accessed October 12, 2026.
- Fiberon PA6-CF20 Technical Data Sheet (V1.1). Polymaker. Technical data sheet. Brass nozzle life about 9 h, drying 100 °C 10 h, annealing 100 °C 16 h. Accessed October 12, 2026.
- Polymaker Material Print Tips. Polymaker Wiki. Manufacturer documentation. Bed at or below 50 °C with doors open, print from heated dryer, moisture conditioning after annealing. Accessed October 12, 2026.
- Prusament PA11 Technical Datasheet (v1.0, 22-07-2026). Prusa Polymers. Technical data sheet. Nozzle, bed, 55 °C chamber, 10 mm³/s, moisture absorption, HDT as printed. Accessed October 12, 2026.
- Prusament PA11. Prusament. Product page. Brass nozzle, PA Nylon sheet, warping, filtration, 122.5 °C after annealing. Accessed October 12, 2026.
- Prusament PA11 Carbon Fiber Technical Datasheet (v1.0, 29-06-2022). Prusa Polymers. Technical data sheet. Hardened nozzle necessary, HDT. Accessed October 12, 2026.
- Drying filament. Prusa Knowledge Base. Manufacturer documentation. PA11 Carbon Fiber drying 90 °C 6 h; keep in a dry box between uses. Accessed October 12, 2026.
- Post-printing procedures (removing, cleaning, annealing, bonding). Bambu Lab Wiki. Manufacturer documentation. PA is crystalline; annealing benefits and risks. Accessed October 12, 2026.
- Advanced Filtration System (glossary). Prusa Knowledge Base. Manufacturer documentation. HEPA and activated carbon; nylon among high-emission materials. Accessed October 12, 2026.
- ELEGOO PAHT-CF product page: Specifications. ELEGOO. Product page. Specifications section: drying, recommended printing settings, physical properties (density, Vicat, HDT at 0.45 MPa) and X-Y/Z mechanical properties; no test standards named. Accessed October 12, 2026.
- Product Comparison. eSUN (official store). Product page. Values appear after choosing a product in the comparison tool: density, HDT at 0.45 MPa, melt flow index, Z tensile strength, X-Y flexural and Izod values, extruder and bed temperature, fan, print speed, build surfaces and printing recommendations; no test standards named. Accessed October 12, 2026.
- OVERTURE EASY NYLON Technical Data Sheet (Version 5.1, August 2024). Overture 3D. Technical data sheet. Recommended printing conditions; dry-state and wet-state mechanical properties. Accessed October 12, 2026.
- Overture Easy Nylon 3D Printer Filament 1.75mm (product page). Overture 3D. Product page. Specs tab drying setting; heat resistance claim of up to 180 °C. Accessed October 12, 2026.
- Siraya Tech Fibreheart PPA TDS. Siraya Tech. Technical data sheet. Print settings, drying, dry and wet HDT, property data. Accessed October 12, 2026.
- Siraya Tech Fibreheart PPA-CF TDS. Siraya Tech. Technical data sheet. Print settings, drying, unannealed and annealed property data, max extrusion volumetric speed. Accessed October 12, 2026.
- Siraya Tech Fibreheart PPA-CF Core TDS. Siraya Tech. Technical data sheet. Print settings, drying, unannealed and annealed property data. Accessed October 12, 2026.
- SUNLU Easy PA Technical Data Sheet (SL-TE-WI-060, version A/1). SUNLU. Technical data sheet. Recommended printing parameters with drying temperature; ISO 75 HDT at 0.45 MPa, ISO 306 Vicat, ISO 1183 density and ISO 527-2 X-Y tensile results from printed specimens. Accessed October 12, 2026.
- Material Performance Comparison. SUNLU Wiki. Manufacturer documentation. Detailed specification table for the SUNLU line, including drying temperature and drying time per product. Accessed October 12, 2026.