All You Need to Know About PLA Recycling

As 3D printing continues to revolutionize manufacturing, prototyping, and hobbyist creation, the issue of plastic waste—particularly from polylactic acid (PLA)—has become a pressing concern. PLA, a biodegradable thermoplastic derived from renewable resources like corn starch or sugarcane, is one of the most popular materials in 3D printing due to its ease of use and environmental credentials. However, failed prints, support structures, and scraps can pile up, contributing to waste. Fortunately, PLA is recyclable, and with the right devices and DIY equipment, you can transform your PLA waste into usable filament, especially when paired with a filament spool winder for seamless integration into your 3D printing workflow. This article dives into the essentials of PLA recycling, exploring the process, benefits, and the best devices and DIY solutions to help you create a sustainable 3D printing ecosystem.

Why Recycle PLA?

Recycling PLA offers significant environmental and economic benefits. By repurposing failed prints, support materials, and other PLA scraps, you reduce plastic waste, minimize the demand for virgin materials, and lower greenhouse gas emissions compared to producing new PLA. Additionally, recycling can cut filament costs by up to 80%, making it a cost-effective solution for makers, educators, and small businesses. While PLA is biodegradable, proper recycling ensures it doesn’t end up in landfills, where decomposition can be slow. With the right tools, you can create a closed-loop system, turning waste into high-quality filament ready for your next print. 

waste filaments

The PLA Recycling Process

Recycling PLA for 3D printing involves several key steps: sorting, cleaning, shredding, drying, extruding, and spooling. Each step requires specific equipment to ensure the recycled filament is consistent and print-ready. Here’s a breakdown of the process:

1. Sorting and Cleaning: Ensure all PLA waste is free of contaminants like other plastics (e.g., PETG or ABS), which can compromise filament quality. Sort by material type using methods like thermal testing—PLA softens at around 60°C, unlike other plastics. Clean the PLA with water or a cloth to remove dirt or debris that could clog extruders or nozzles.

2. Shredding: PLA waste must be broken down into small, uniform granules for extrusion. A shredder or grinder reduces failed prints and scraps into manageable pieces.

3. Drying: PLA is hygroscopic, meaning it absorbs moisture, which can cause bubbles or defects in the filament. Drying the granules at 90°C for about an hour (with the oven door slightly open) ensures moisture-free material.

4. Extrusion: The dried granules are fed into a filament extruder, which melts the PLA and pushes it through a nozzle to form a continuous filament, typically 1.75mm or 2.85mm in diameter.

5. Cooling and Spooling: The extruded filament is cooled (via air or water) and wound onto a spool using a filament spool winder to maintain consistent tension and prevent tangles.

6. Quality Testing: Measure the filament diameter (aim for ±0.05mm tolerance) and test it with small prints to check for strength, printability, and consistency.

Devices and DIY Equipment for PLA Recycling

To recycle PLA effectively, you’ll need a combination of specialized devices and, in some cases, DIY solutions. Below are some of the best options, all compatible with filament spool winders for a streamlined recycling process.

1. Filabot EX2 and Filabot Spooler

The Filabot EX2 is a desktop filament extruder designed for recycling PLA and other plastics like ABS and PETG. It features precise temperature control and a screw feeder for consistent extrusion. Paired with the Filabot Spooler, it ensures uniform filament winding with adjustable tension, producing spools ready for 3D printing. The system is user-friendly, with a compact design suitable for home or small workshop use. Filabot’s ecosystem also includes a shredder for processing PLA waste into granules, making it a complete solution. 

· Pros: High-quality filament output, reliable spooling, supports multiple plastics.

· Cons: Higher cost (around $2,700 for the EX2), requires separate shredder.

· Spool Winder Compatibility: The Filabot Spooler integrates seamlessly, with automated tension control for perfect spools.

2. 3devo Filament Maker ONE and GP20 Plastic Shredder

3devo offers a comprehensive recycling system with the GP20 Plastic Shredder and Filament Maker ONE. The shredder processes PLA waste into uniform granules, while the Filament Maker ONE extrudes them into filament with real-time diameter monitoring for precision (±0.05mm). The upcoming Filament Maker TWO promises faster, more sustainable extrusion. 3devo’s system includes an integrated cooling system and works with their spool winder to produce print-ready filament. This setup is ideal for labs, classrooms, and small businesses focused on sustainability. 

· Pros: End-to-end solution, high precision, excellent customer support.

· Cons: Expensive (starting at $5,000), steep learning curve for beginners.

· Spool Winder Compatibility: 3devo’s winder ensures consistent tension and is adjustable for various spool sizes.

3. Felfil Evo and Felfil Spooler

The Felfil Evo is a compact, open-source filament extruder tailored for recycling PLA waste. It’s designed for makers and educators, allowing experimentation with custom materials. The Felfil Spooler complements the extruder by winding filament with precise tension control, ensuring tangle-free spools. The system also includes a shredder for processing PLA scraps, making it a budget-friendly option for DIY enthusiasts. 

· Pros: Affordable (around $1,500 for the complete system), open-source, educational focus.

· Cons: Slower extrusion rate (0.4 kg/h), less automation than premium models.

· Spool Winder Compatibility: The Felfil Spooler is designed specifically for the Evo, with manual and automatic modes for flexibility.

4. QiTech Extruder and Pro Winder

QiTech’s 6th-generation extruder and Pro Winder are built for precision and ease of use. The extruder features a pressure sensor and cloud-connected app for monitoring extrusion parameters, while the Pro Winder uses intelligent speed control and a laser-calibrated system to ensure perfectly wound spools. The QiTech Shredder processes PLA waste into granules, and their Airpath cooling unit maintains optimal filament temperature during winding. This system is ideal for advanced users seeking data-driven recycling.  

· Pros: App-based control, high precision, modular design.

· Cons: Higher cost, requires technical expertise.

· Spool Winder Compatibility: The Pro Winder is highly compatible with QiTech’s extruder and third-party systems, offering Wi-Fi-controlled spooling.

5. DIY Solutions: RepRapable Recyclebot

For budget-conscious makers, the RepRapable Recyclebot is an open-source, DIY filament extruder costing less than $700 to build. It can process PLA at 0.4 kg/h with a diameter tolerance of ±4.6%. Paired with a DIY spool winder (often built using Arduino and stepper motors), it offers an affordable way to recycle PLA. The Precious Plastic project provides plans for shredders and extruders, while a homemade drybox can handle drying. This approach requires more hands-on effort but is highly customizable. 

· Pros: Low cost (filament production at 2.5 cents/kg), open-source, community-driven.

· Cons: Requires assembly and technical skills, less consistent filament quality.

· Spool Winder Compatibility: DIY winders can be built to work with the Recyclebot, using tension units and guides for uniform spooling.

6. ProtoCycler V3

The ProtoCycler V3 is a robust all-in-one solution with an integrated extruder, cooling system, and intelligent spooling system. It includes an optional grinder for shredding PLA waste and features AI-powered Command Center software to optimize extrusion parameters. Certified for safety in labs and classrooms, it’s a versatile choice for sustainable 3D printing. 

· Pros: All-in-one design, AI optimization, safe for educational settings.

· Cons: Premium price, limited to specific plastics.

· Spool Winder Compatibility: The built-in spooling system ensures consistent tension and is compatible with standard spool sizes.

Choosing the Right Filament Spool Winder

A filament spool winder is critical for producing usable filament. Key features to look for include:

· Tension Control: Ensures filament is wound tightly to prevent tangles.

· Filament Guide: Distributes filament evenly across the spool for uniform winding.

· Speed Adjustment: Matches the extruder’s output to avoid overstretching or loose spools.

· Compatibility: Works with 1.75mm or 2.85mm filament and various spool sizes.

The QiTech Pro Winder and Filabot Spooler stand out for their intelligent speed control and compatibility with most extruders. For DIY setups, a custom winder built with a Nema stepper motor and Arduino can be calibrated to match your extruder’s output. 

Tips for Successful PLA Recycling

· Maintain Material Purity: Mixing PLA with other plastics (e.g., PETG) can clog extruders or weaken filament. Use thermal or density tests to confirm PLA.

· Monitor Diameter: Measure filament diameter regularly during extrusion to stay within ±0.05mm for optimal printability.

· Dry Thoroughly: Moisture in PLA can cause bubbles or stringing. Use a dedicated dryer or oven for best results.

· Test Small Prints: Print small test objects to check filament strength and adhesion before using it for larger projects.

· Ventilation: Extrusion releases fumes, so ensure proper ventilation to maintain a safe workspace.

Challenges and Considerations

While PLA recycling is rewarding, it’s not without challenges. Recycled filament may degrade slightly with each cycle, leading to reduced strength (e.g., 6-12% weaker than virgin PLA). Contamination from mixed plastics or improper drying can cause clogs or brittle filament. High-end systems like 3devo or Filabot are expensive, while DIY solutions require technical expertise. Additionally, recycling is most cost-effective for those generating significant PLA waste, such as print farms or labs. 

Environmental and Economic Impact

Recycling PLA reduces plastic waste and supports a circular economy. It lowers the environmental footprint by decreasing reliance on virgin materials and can save up to 80% on filament costs compared to commercial spools. For hobbyists, recycling fosters creativity by enabling experimentation with custom filament blends, while businesses and educators can promote sustainability and reduce operational costs. 

Conclusion

Recycling PLA is a practical and sustainable solution for managing 3D printing waste. With devices like the Filabot EX2, 3devo Filament Maker, Felfil Evo, QiTech Extruder, ProtoCycler V3, or DIY options like the RepRapable Recyclebot, you can transform PLA scraps into high-quality filament. Pairing these systems with a compatible filament spool winder ensures professional-grade spools ready for your 3D printer. By embracing PLA recycling, you not only save money but also contribute to a greener future, making every failed print a new opportunity for creation. Start your recycling journey today and turn waste into wonder!