Strength
What filament should I use for a strong part?
First in this ranking: Bambu Lab PA6-CF.
- Nozzle250–290 °C
- Bed80–100 °C
- SpeedNot listed
- Dry—
- Density1.09 g/cm³
Ranked filaments
| Rank | Filament | Material | Nozzle | Bed | Price / kg | Datasheet | Retailer |
|---|---|---|---|---|---|---|---|
| 1 | Bambu Lab PA6-CFThe structural step up. Datasheet linked from the record. Check the hardened-nozzle cell before buying it for a brass nozzle. | PA/CF | 250–290 | 80–100 | Not listed | Datasheet | Not configured |
| 2 | Prusament PETGPrusa calls PETG tenacious and uses that class for mechanical parts. Easier than nylon, and the record has a datasheet. | PETG | 240–260 | 70–90 | Not listed | Datasheet | Not configured |
| 3 | Polymaker PolyMax PLAAn impact-modified PLA, still PLA. Useful when the part is indoors and the printer is open. It does not change Prusa’s warning about PLA and heat. | PLA | 190–230 | 25–60 | Not listed | Datasheet | Not configured |
| 4 | eSUN 3D PLA+The PLA+ people name when they want a tougher easy filament. Ranked last because ‘plus’ is not a measured strength in this catalog. | PLA+ | 190–230 | 50–70 | Not listed | Not listed | Not configured |
How the ranking was chosen
“Strong” without a load, a temperature, or a layer direction is not a material. The ranking assumes a stiff part that has to take a load, indoors unless you also read the heat guide.
Pros and cons
Pros
- The top row is a fiber-filled nylon with a datasheet, which is the material class Prusa groups with composites.
- PETG and PolyMax PLA give a strong-enough part on printers that cannot run nylon.
Cons
- This catalog has no tensile strength and no price per kilogram. The table will not pretend otherwise.
- PLA+ from one brand is not the same formula as PLA+ from another. The eSUN row is that product, not a universal grade.
Printer considerations
- PA6-CF needs a nozzle temperature in the range the product page lists, and a nozzle that can survive fiber. Read both pages before calling it compatible.
- PETG wants a heated bed. Prusa’s PETG article uses about 85 °C as the bed example; the table shows the spool’s own listed bed, which may differ.
- Strength is also walls, infill, and layer direction. A filament change does not fix a part printed with two walls along the stress.
What the community says
Asked how big the jump is, r/3Dprinting describes PLA as fine for light-duty parts, PETG as the more durable everyday material, and TPU as the impact-resistant one that is flexible rather than rigid. Fiber-filled nylon is what people move to when a bracket has to be both stiff and hot, which is a different request from ‘stronger PLA.’
Sources & notes
Accessed 14 October 2026.
- PETG, Prusa Knowledge Base manufacturer
- PLA, Prusa Knowledge Base manufacturer
- Prusa filament material guide manufacturer
- Bambu Lab PA6-CF technical data sheet datasheet
- Prusament PETG technical data sheet datasheet
- How big is the jump between PLA, PETG, and TPU?, r/3Dprinting reddit
Related questions
- What filament should a beginner use?Beginners
- What filament should I use for heat?Heat resistance
- Are carbon fiber filaments worth it, and do I need a hardened nozzle?Carbon fiber
- How do I print nylon, and is it worth it?Nylon
Questions
Is PolyMax PLA as strong as nylon?
No. It is ranked as the easy indoor PLA that is tougher than a brittle plain PLA. Heat and a real structural load still point at PETG or PA6-CF.
Why is TPU not on this list?
TPU survives impact by bending. The flexible guide covers it. A stiff bracket is a different part.