Best Filaments for Functional 3D Printed Parts

1. Understanding Functional Parts

Functional parts are 3D printed objects that must perform a specific job; they’re not just visual prototypes or decorative items. They often replace traditionally manufactured parts and must handle mechanical loads, environmental stress, and long-term use.

Examples include:

• Mechanical Components: gears, pulleys, clips, hinges, and levers
• Structural Elements: brackets, mounts, joints, and frames
• Industrial Fixtures: jigs, assembly guides, and machine holders
• Consumer Applications: replacement parts, tool handles, phone mounts, and drone housings

Unlike aesthetic prints, functional parts are expected to endure stress, heat, friction, and sometimes impact. Because of that, the choice of filament affects strength, flexibility, chemical resistance, and dimensional stability.

4. Detailed Overview of Each Filament

PLA+ / Tough PLA

PLA+ is a modified version of standard PLA with added durability and slight flexibility. It prints easily with minimal warping and delivers clean, detailed parts. However, it loses structural integrity under heat or continuous mechanical stress.

Advantages:

• Extremely easy to print and reliable for quick prototyping
• Sharp details and smooth surface finish
• Compatible with nearly all 3D printers

Disadvantages:

• Low heat resistance (softens around 60°C)
• Brittle under repeated stress

Best Uses:
Fixtures, visual prototypes, non-load-bearing jigs, alignment tools, or test-fit models.

Link to Product:

https://shop.spectrumfilaments.com/eng_m_Our-offer_Materials_PLA_Spectrum_PLA-Tough-2648.html

PET-G / PCTG

PETG (Polyethylene Terephthalate Glycol) and its newer counterpart PCTG (PolyCyclohexylene Dimethylene Terephthalate Glycol) combine the toughness of ABS with the easy printability of PLA. They offer excellent strength, chemical resistance, and impact durability.

Advantages:

• Great balance between strength and flexibility
• Resistant to chemicals and moisture
• Minimal warping and easy layer adhesion

Disadvantages:

• Can be stringy if not printed with proper retraction settings
• Slightly less stiff than ABS or PC

Best Uses:
Functional parts such as brackets, mechanical joints, machine guards, or electronics enclosures that need durability and reliability.

Link to Product:

https://shop.spectrumfilaments.com/eng_m_Our-offer_Materials_PETG_Spectrum_PETG-MATT-2672.html

ABS (Acrylonitrile Butadiene Styrene)

ABS is an engineering-grade filament known for its toughness, machinability, and moderate heat resistance. It’s been used for decades in automotive and consumer products like LEGO bricks. However, it requires controlled printing conditions to prevent warping and cracking.

Advantages:

• High impact strength and heat tolerance
• Can be post-processed easily (sanding, acetone smoothing)
• Suitable for load-bearing applications

Disadvantages:

• Prone to warping without an enclosure
• Emits noticeable odor when printing

Best Uses:
Automotive parts, tools, or enclosures exposed to heat or mechanical load.

Link to Product:

https://shop.spectrumfilaments.com/eng_m_Our-offer_Materials_ABS_Spectrum_smart-ABS-2686.html

ASA (Acrylonitrile Styrene Acrylate)

ASA is often called the outdoor version of ABS. It retains all of ABS’s toughness but adds superior UV and weather resistance. This makes it a favorite for parts that will face sunlight, rain, or temperature changes.

Advantages:

• Excellent UV and weather resistance
• High strength and dimensional stability
• Smooth finish, even for larger parts

Disadvantages:

• Requires enclosure and stable printing conditions
• Slightly more expensive than ABS

Best Uses:
Outdoor components, automotive trims, signage mounts, or drone parts that need UV protection.

Link to Product:

https://shop.spectrumfilaments.com/eng_m_Our-offer_Materials_ASA_Spectrum_ASA-275-2693.html

Nylon (PA)

Nylon (Polyamide) is one of the strongest and most durable filaments available. It’s both tough and flexible, making it ideal for parts that need to endure repetitive stress or impact. However, it absorbs moisture quickly, which can affect print quality if not stored properly.

Advantages:

• High toughness, flexibility, and wear resistance
• Excellent for moving or interlocking parts
• Resistant to many chemicals and oils

Disadvantages:

• Hygroscopic (needs dry storage)
• Requires high printing temperature and bed adhesion aids

Best Uses:
Gears, hinges, snap-fit parts, bushings, or mechanical linkages.

Link to Product:

https://shop.spectrumfilaments.com/eng_m_Our-offer_Materials_PA_Spectrum_PA6-Low-Warp-2709.html

Polycarbonate (PC)

Polycarbonate is an industrial-grade filament known for its extreme strength and heat resistance. It can handle high mechanical loads and sustain performance even in demanding environments. However, it requires high printing temperatures and an enclosed printer.

Advantages:

• Exceptional strength-to-weight ratio
• Can withstand temperatures above 110°C
• Impact-resistant and transparent (depending on brand)

Disadvantages:

• Needs high-temp printer and enclosure
• Prone to warping without proper setup

Best Uses:
Structural parts, protective housings, lighting enclosures, or mechanical mounts used in high-heat environments.

Link to Product:

https://shop.spectrumfilaments.com/eng_m_Our-offer_Materials_PC_Spectrum_PC-275-2722.html

Carbon Fiber Composites (CF-PETG, CF-Nylon, CF-PC)

Carbon fiber-infused filaments combine high-performance base materials with finely chopped carbon fibers, creating a composite that’s lightweight, rigid, and strong.  Perfect for professional and engineering applications.

Advantages:

• Extremely stiff and lightweight
• Excellent dimensional stability
• Professional matte surface finish

Disadvantages:

• Abrasive — requires hardened steel nozzle
• Brittle in thin cross-sections

Best Uses:
Drone frames, robotic arms, functional brackets, and engineering-grade components.

Link to Product:

https://shop.spectrumfilaments.com/eng_m_Our-offer_Materials_PC_Spectrum_PC-CF-2723.html