Recycled PLA Filament

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Lisa Ernst · 21.11.2025 · Technology · 12 min

When we first started experimenting with recycled PLA filament in the 33d.ch workshop, the half-empty spool of standard PLA lay next to the machine – and the question hung in the air: is the recycled stuff really good enough for everyday use, or is it just good for the conscience? After a few calibration cubes, failed clips, and a rather deformed housing, it was clear: the differences to classic PLA are smaller than many think – but in everyday life, they decide whether your parts hold up or break at the wrong moment. Studies show that recycled PLA can noticeably reduce environmental impact and greenhouse gas emissions with similar print quality, provided recycling and energy usage are properly organized ( sciencedirect.com) ( ncbi.nlm.nih.gov).

In this post, we summarize what we at 33d.ch pay attention to with recycled PLA: from the basics and preparation to step-by-step settings on the printer – including the typical pitfalls we encountered ourselves at the beginning. The target audience includes hobby makers, schools, and SMEs who want to build a noticeably more sustainable 3D printing setup with reasonable effort, without making big compromises on print quality.

Basics & Advantages of Recycled PLA

When using recycled PLA filament , there are essentially two things: Firstly, the print quality must be right – meaning a clean print, reasonable dimensional accuracy, and sufficient durability for your application. Secondly, you want to improve your ecological footprint without having to worry about clogged nozzles or brittle parts with every print run ( sciencedirect.com).

PLA itself is a bioplastic, usually made from corn or sugarcane starch, which can have a more favorable CO₂ footprint compared to traditional petroleum plastics – especially when energy consumption and disposal are considered ( ijert.org) ( sciencedirect.com). Recycled PLA (rPLA) is produced when production waste, faulty parts, or used PLA components are shredded, processed, and extruded into filament again – often as a mixture of recycled and virgin material, sometimes with a very high recycling content ( mdpi.com) ( filamentive.com).

Several studies show that the mechanical properties of recycled PLA in terms of tensile and flexural strength are often only slightly below those of virgin PLA, sometimes even very similar, as long as the material has not been melted too many times and the process is managed cleanly ( mdpi.com) ( sciencedirect.com) ( sciencedirect.com). Manufacturers like Prusa or Filamentive report that their rPLA filaments are as easy to print in everyday life as standard PLA and are suitable for prototypes, gadgets, enclosures, and everyday objects ( prusa3d.com) ( filamentive.com).

Regarding the ecological footprint: a life cycle assessment of PLA shows that recycling PLA causes significantly lower greenhouse gas emissions than incineration or landfilling, as material and energy are reused ( ncbi.nlm.nih.gov). Manufacturers of recycled filaments refer to CO₂ reductions of around 35 to over 50 percent compared to non-recycled filament, considering production and material origin ( filamentive.com).

If you generally want to print more sustainably, you can recycled PLA combine with recycled PETG (rPETG), rPET, or recycled polypropylene. This way, you cover different temperature ranges and load capacities while sticking to materials with a reduced resource footprint ( materially.eu) ( 3dtrcek.com) ( packagingeurope.com).

rPLA in Comparison – Rough Orientation

Application Standard PLA Recycled PLA rPETG / rPET
Prototypes, decoration Very easy to print Very easy to print Good, slightly more challenging
Functional parts indoor Limited temperature resistance Similar, potentially slightly more brittle Significantly more robust and tough
Ecological balance Better than ABS, but virgin material Significantly less primary material Less primary material, more complex process

In our projects at 33d.ch, we use rPLA wherever parts are regularly replaced or primarily have optical and light mechanical requirements – for example, sample parts for customers, holders in laboratories, or simple enclosures for sensors. For heavily loaded clips and parts in mechanical engineering, we often opt for rPETG or technical plastics, but consciously keep rPLA in mind for everything that should hit the 'sweet spot' of usability and more sustainable material.

Preparation & Setup

Before you start, a clean framework is worthwhile: you need an FDM 3D printer with a well-calibrated movement and extrusion system, ideally with a heated print bed and a location without drafts ( lancashire.ac.uk). For recycled PLA filament , the same types of printers are suitable as for standard PLA, but filament handling and cooling are a bit more important. Many rPLA filaments run at 190 to 220 °C at the nozzle and 40 to 60 °C on the heated bed – the exact values are in the data sheet ( filamentive.com) ( prusament.com).

A 20 mm calibration cube and a small functional part, such as a hinge or a clip that you will actually use later, have proven to be good test objects ( printables.com) ( printables.com). This way, you can quickly see if dimensional accuracy, surface, and layer adhesion are correct.

A dry storage location for your filament is a must: a closed box with desiccant, ideally with a hygrometer. rPLA also absorbs moisture, which shows up as bubbles, a rough surface, and poor layer adhesion ( nice-cdn.com). If the filament 'crackles' during printing or extrudes very matte and porous, a drying cycle is worthwhile – often at around 50 °C for a few hours ( nice-cdn.com) ( filamentive.com).

Quick Check Before the First rPLA Print

In our workshop, this quick check has proven useful before the first print with a new rPLA spool: The printer is stable and draft-free, the bed is leveled and clean, a functional PLA profile is set in the slicer, the filament is dry and free of knots, test models and calipers are ready, and you have a rough idea of how long the print will take and approximately how much material will be used ( 3dbenchy.com) ( ncbi.nlm.nih.gov). If these points are checked off, the chance is very high that the first rPLA run will be exciting rather than frustrating.

Regarding power consumption, we see values around 100 to 150 watts in running operation for typical desktop FDM printers in customer projects, depending on the device and temperature. Over several hours, this quickly adds up to 0.8 to 1.2 kWh ( snapmaker.com) ( solartechonline.com). If you print several smaller parts at once instead of each holder individually, you save not only time but also energy.

Step-by-Step: Introducing rPLA into Everyday Use

Recycled PLA filament in print – clean print despite recycled content.

Quelle: filamentive.com

Recycled PLA filament in print: in many cases, the print is barely distinguishable from classic PLA.

Step 1: Define the goal and choose test parts. Consider what you want to cover with recycled PLA filament : decoration, prototypes, enclosures, lightly loaded functional parts, or recurring small series ( printables.com) ( printables.com). We internally like to use 3D Benchy or small enclosures to see typical problem areas like overhangs and bridges right away ( 3dbenchy.com).

Step 2: Create a reference print with standard PLA. First, print both test parts with your usual PLA profile (e.g., 0.2 mm layer height, 3 perimeters, 15-30% infill) at known temperatures and fan settings ( filamentive.com). Note down the target nozzle temperature, bed temperature, speed, fan profile, and retract values – we have such a 'base profile' visible on the wall for each printer. Later, you can compare rPLA directly against it ( obico.io).

Step 3: recycled PLA filament set according to the datasheet. Then switch to rPLA, adopt the PLA profile, and only adjust the temperatures – for example, 200–215 °C at the nozzle and 50–60 °C on the bed for Prusament PLA Recycled ( prusament.com) ( prusa3d.com). Many manufacturers recommend the same or slightly higher target nozzle temperature as for standard PLA, because rPLA melts slightly differently depending on the mix ( mdpi.com) ( sciencedirect.com). We usually start in the middle of the recommended range and carefully examine the first two layers.

Step 4: Check print quality and dimensional accuracy. After printing the rPLA cube, measure the edges with the caliper and compare them to 20 mm – deviations of ±0.1–0.2 mm are normal for many desktop printers ( printables.com). Check the side surfaces in the light: clean layers, no pronounced zippers, sharp corners like with the PLA reference ( 3dbenchy.com). If you see fine gaps or under-extrusion, a 5 °C increase in temperature or a slight flow correction usually helps.

Step 5: Test layer adhesion and function. With the hinge or clip, it gets serious: open, bend, click. Studies on recycled PLA show that tensile strength only decreases moderately with controlled recycling and remains close to virgin PLA ( mdpi.com) ( sciencedirect.com). In practice, this means for us: if a clip doesn't break along the layers during normal use, but only under heavy overload, we use rPLA for similar parts. However, if the clip has to withstand strong bending stress daily, we switch to PETG or rPETG ( 3dtrcek.com).

Step 6: Compare warping, odor, and surface. Pay attention at the start of the print whether corners lift or the first layer adheres unevenly. Many rPLA filaments behave very similarly to good PLA in terms of warping – i.e., practically warp-free with appropriate bed temperature and clean Z-offset settings ( filament2print.com) ( spectrumfilaments.com). In terms of odor, we usually notice no relevant difference to normal PLA in the workshop, which is a clear comfort advantage compared to ABS or ASA – good ventilation remains a must, however ( 3d-fabrik.at) ( filamentive.com).

Step 7: Optimize power consumption and slicer strategy. Studies on the sustainability of FFF printing show that, in addition to the material, print duration, infill strategy, and power mix are crucial: shorter print times, bundled jobs, and optimized infill patterns save energy and material ( mdpi.com) ( ncbi.nlm.nih.gov). An 8-hour print using about 0.1–0.15 kWh per hour roughly adds up to 0.8–1.2 kWh ( snapmaker.com). If you model and slice your parts so that they are not more massive than necessary, you save both electricity and rPLA ( solartechonline.com) ( sciencedirect.com).

Common Problems & Solutions

Uneven extrusion is one of the classic issues with recycled PLA filament: visible lines, thin spots, gaps in the infill. This is often due to fluctuating filament diameter or moisture in the material ( filamentive.com). The combination of a good manufacturer (with documented diameter tolerance), dry storage, and slightly increased nozzle temperature often provides peace of mind in the print image ( filamentive.com) ( mdpi.com).

A second issue that annoyed us at the beginning: nozzle clogs with individual rPLA batches. Studies with recyceltem PLA describe that clogging occurred in some cases while the comparison sample with virgin PLA ran cleanly ( sciencedirect.com) ( researchgate.net). Our practical solution: hotends that are easy to clean, regular 'cold pulls', and in stubborn cases, a clear cut – different spool, different batch, different manufacturer.

We see the third problem mainly with functional parts: brittle fracture behavior after prolonged use or at lower temperatures. PLA generally loses toughness when it is heated repeatedly or has aged significantly ( ncbi.nlm.nih.gov) ( sciencedirect.com). Repeatedly recycled PLA shows a decrease in impact strength in studies, while tensile strength often remains in an acceptable range with good process control ( mdpi.com) ( sciencedirect.com). For us, this means: rPLA for moderately stressed parts and prototypes, not for safety-critical parts or spring mechanisms with continuous oscillation.

A real-life example from our workshop: A customer wanted strong clips for cable chains made of rPLA because the material fit the project ecologically. The first print looked great, but some parts broke along the layers when clipping them in. We then increased the nozzle temperature, chose more perimeters, and slightly rounded the geometry – this made the clips significantly more robust ( 3dbenchy.com) ( ncbi.nlm.nih.gov). For the final, permanently stressed clips, we eventually switched to rPETG – rPLA remained in the project for prototypes and optical parts ( 3dtrcek.com).

Variants & Adjustments

3D printed plant pot made from recycled PLA filament.

Quelle: filament.ch

From waste to product: A 3D printed plant pot made from recycled PLA shows how everyday-friendly sustainable filaments can be.

Once your rPLA profile is set, you can gradually expand your sustainable setup. An obvious direction is other 'green' filaments, such as recycled PETG, which is derived from defined recycling streams and is designed for higher temperatures and greater loads ( 3dtrcek.com) ( formfutura.com). Such materials combine robust performance with reduced use of primary raw materials – if recycling and production are transparently documented ( materially.eu).

Recycled PP- or PE-based filaments are also interesting, where research institutes and companies are actively working to transform packaging waste into printable filaments ( packagingeurope.com) ( materialdistrict.com). Projects like the collaboration between Fraunhofer IFAM and universities show that high-quality 3D printed products can be made from household packaging if sorting and processing work well ( fraunhofer.de). However, in practice, we often see that such filaments are still more experimental – in everyday life, we use rPLA and rPETG much more frequently today.

There are also tweaks to be made with the spool: rPLA manufacturers use cardboard cores or complete cardboard spools made from recycled, sometimes FSC-certified materials ( spectrumfilaments.com) ( formfutura.com) ( filamentive.com). Prusament combines a cardboard core with light side parts made of recycled polycarbonate for PLA Recycled ( prusa3d.com) ( prusa3d.com). At 33d.ch, we consistently sort empty spools – cardboard goes into waste paper or is repurposed for holders and winding projects, robust plastic spools are reused internally as long as they are mechanically sound.

If you want to go a step further, you can shred failed prints and remnants yourself and extrude them again. Desktop shredders like the Felfil Shredder+ turn old prints into pellets ( felfil.com). Systems like 3devo, ProtoCycler, or Recyclebot combine shredding and extrusion into new filament ( 3devo.com) ( redetec.com) ( wikipedia.org). Before investing here, we recommend user reports and guides – reproducibly good filament is more demanding than it appears at first glance ( filamentive.com) ( arxiv.org).

Quelle: YouTube

Recommended Video: This YouTube video demonstrates in practice how a specific rPLA filament behaves during printing, with close-ups of surfaces and sensible starting settings.

FAQ & Conclusion on Recycled PLA

Recycled PLA filament from sorted plastic waste.

Quelle: digitmakers.ca

Recycled PLA filament: new material for 3D printing from waste – sensible if quality and process are right.

Question 1: How strong is recycled PLA compared to normal PLA?
Laboratory studies show that recyceltes PLA in tensile strength and stiffness, often in the same range as virgin PLA with controlled recycling, with sometimes slightly lower impact strength ( mdpi.com) ( sciencedirect.com). In our workshop, we mainly notice the difference with very thin or heavily stressed clips – for enclosures, holders, and sample parts, rPLA usually works without problems.

Question 2: For which applications is rPLA particularly suitable – and where not?
rPLA works very well for prototypes, decorative parts, indoor enclosures, and lightly loaded functional parts ( filamentive.com) ( spectrumfilaments.com). It is less suitable – like standard PLA – for parts above approx. 50–60 °C ambient temperature or for parts with high impact and continuous bending stress, such as spring mechanisms or exterior parts in direct sunlight ( prusament.com) ( filament2print.com). Here, we prefer to use rPETG or technical plastics ( 3dtrcek.com).

Question 3: How should I store recycled PLA correctly?
rPLA should be stored cool, dry, and protected from light, just like normal PLA. Manufacturers recommend closed boxes with desiccant, especially for cardboard spools ( nice-cdn.com) ( filamentive.com) ( formfutura.com). If the filament noticeably 'crackles' or prints very roughly, a drying run at about 50 °C usually helps – this has saved several supposedly 'bad' spools at 33d.ch.

Question 4: Is a personal filament recycler worthwhile for makers, schools, or SMEs?
Systems like 3devo, ProtoCycler, or Recyclebot show that it is technically possible to reprocess failed prints into filament ( 3devo.com) ( redetec.com) ( wikipedia.org). However, in practice, we see that consistent quality, precise diameter, and reproducible properties require considerable know-how and maintenance ( arxiv.org) ( filamentive.com).

Question 5: How significant is the ecological advantage really?
Life cycle assessments show that PLA recycling causes significantly lower greenhouse gas emissions than incineration or landfill ( ncbi.nlm.nih.gov) ( sciencedirect.com). Manufacturers speak of CO₂ savings in the range of about a third and more when switching to recycled filaments ( filamentive.com). In combination with short print times, sensible infill strategies, and – where possible – renewable energy, the effect becomes much more noticeable in everyday life ( ncbi.nlm.nih.gov) ( mdpi.com).

Mini-Conclusion: What you can get out of rPLA

Quelle: YouTube

Recommended video: This video clearly shows how failed prints can be recycled into new filament – including the pitfalls that should be considered for your own recycling setup.

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