Recyclable 3D printing: rPETG, rPLA and how to reduce waste

Recycled 3D printing is a topic getting increasing attention — and for good reason. Plastic waste from production is a real problem, and 3D printing is no exception. Failed prints, support structures and prototype iterations generate waste, and the question is what can be done about it.

At Maker Factory we approach waste reduction from several angles: material choice, design optimization, and process experience that minimizes failed prints. This article gives you the overview of what can be recycled, what can't, and where the biggest gain lies.

What can be recycled in 3D printing?

All thermoplastics can, in principle, be recycled. Thermoplastics melt when heated and solidify again on cooling — that property makes it possible to granulate used parts and turn them into new filament. That applies to the most widely used FDM materials: PLA, PETG, ABS and ASA.

The process is, in principle, simple: used parts and failed prints are granulated in a shredder, the pellets are melted in an extruder, and new filament is spooled. In practice, however, there are challenges:

• Quality loss per cycle: The polymer chains shorten with each re-melt. That means lower strength, changed flow characteristics, and potentially worse surface finish after two to three recycling cycles.
• Contamination: Mixing different plastic types ruins the material's properties. PETG and PLA look similar but behave completely differently at print temperature. Sorting is critical.
• Color variation: Recycled filament rarely has a consistent color. That's fine for functional parts, but problematic for visual prototypes.
• Additives and fibers: Carbon-fiber-reinforced materials like PA6-CF and PETG-CF are harder to recycle, because the fibers wear down equipment and change flow properties on reuse.

SLA resin materials (UV-curing) are thermosets and cannot be recycled by re-melting. Once resin is cured, the chemical reaction is irreversible. SLA waste has to be disposed of as plastic waste — it can't be converted into new resin.

rPETG and rPLA: recycled filament in practice

Several filament manufacturers now offer recycled variants of the most popular materials. rPETG is typically made from recycled PET bottles or industrial PETG waste, while rPLA is produced from PLA production offcuts and failed prints.

rPETG is the most mature recycled filament type. The material prints almost identically to virgin PETG: the same temperatures (230-250°C), good layer bonding and acceptable strength. For functional prototypes, jigs and fixtures, rPETG is a fully usable alternative.

rPLA is available but more variable in quality. Printability depends on the purity and processing of the source material. For visual models and proof-of-concept it works fine, but for parts with tight tolerances we still recommend virgin material.

How much waste does 3D printing actually produce?

3D printing is an additive process — material is only laid down where it's needed. That's fundamentally different from subtractive methods like CNC machining, where you start with a block and remove all the excess material. In practice, that means:

• Material utilization of 70-98% for FDM printing, depending on geometry and support needs.
• CNC machining typically has 60-80% waste — most of the raw material ends up as chips.
• Injection molding has minimal production waste, but requires tooling costing DKK 50,000-500,000 and only makes sense at high volumes.

The primary waste in 3D printing comes from three sources: support structures (necessary for overhangs), failed prints (adhesion issues, support failures, power outages) and prototype iterations (designs that need adjusting). At Maker Factory we reduce all three through experience and process optimization.

Five strategies to reduce 3D printing waste

1. Design optimization before printing

The most effective waste reduction happens before the print starts. By orienting the part correctly, the amount of support can be reduced dramatically — in many cases support can be eliminated entirely. Our design team optimizes geometry specifically for the chosen print process, typically reducing material use by 10-30%.

2. Correct material choice the first time

Choosing the right material from the start eliminates reprints. A part that fails in PLA because it can't withstand the heat, and then has to be reprinted in ASA, has doubled its material use. Our material guide and advice help you get it right the first time.

3. Process experience and machine optimization

Failed prints are the biggest source of waste in 3D printing. Experience with materials, print profiles and machine calibration significantly reduces the failure rate. At Maker Factory we run Bambu Lab printers with optimized profiles for each material — our failure rate on batch production is under 3%.

4. Intelligent support strategy

Support structures are necessary for overhangs and bridges, but they end up as waste. By designing with the printer in mind — the 45° rule, self-supporting geometries, strategic part orientation — the amount of support can be minimized. Tree supports instead of classic grid supports can cut support material by up to 60%.

5. Consolidating prototype iterations

Instead of printing a whole part to test one feature, you can print test coupons or partial sections. That reduces material use per iteration and speeds up the design process. We often advise customers to split the test phase into targeted partial prints rather than full prototypes.

Design optimization as waste reduction

The most overlooked sustainability strategy in 3D printing is design optimization. A part designed for 3D printing uses less material, needs less support, and has fewer failed prints than a part simply converted from a CNC design.

Concrete techniques include: topology optimization that removes material where it doesn't contribute to strength, variable wall thickness that places material exactly where it's needed, and lattice structures that replace solid sections with lightweight grid structures. A topology-optimized bracket can use 40-60% less material than a conventional design — with equal or better strength.

At Maker Factory our designers work in Autodesk Fusion 360, which has built-in topology optimization tools. We use them routinely on industrial parts where weight and material use are critical parameters. The results are often visually surprising — organic shapes that resemble something from nature, but are mathematically optimized for the job.

3D printing vs. traditional production: waste comparison

3D printing has an inherent advantage when it comes to material waste — but it varies with volume and complexity.

At low volumes (1-500 parts), 3D printing is almost always the most material-efficient method. At high volumes, injection molding wins on per-unit cost and waste per part, but requires tooling that itself consumes resources. The crossover point depends on the part's complexity and size — we'll help you assess what makes the most sense for your project.

Materials at Maker Factory

We offer a wide range of FDM and SLA materials. Here are the most relevant ones in a recycling and sustainability context:

• PETG — the most recycling-friendly thermoplastic. Good strength, chemical resistance and durability. Also available as rPETG.
• PLA — bio-based and recyclable as a thermoplastic. Best for visual prototypes. Read more in our article on biodegradable materials.
• ABS — classic industrial plastic, well-established recycling infrastructure.
• ASA — UV-stable variant of ABS, ideal for outdoor use with a long lifespan.
• PA6-CF — carbon-fiber nylon for demanding industrial applications. High durability reduces the need for reproduction. See our in-depth PA6-CF guide.
• TPU — flexible material, recyclable but requires specialized processing.

What does recycled 3D printing cost?

Recycled filament (rPETG, rPLA) is typically 10-20% cheaper than virgin material. The saving is modest, but it adds up for large runs and non-critical parts. The real saving, however, lies in waste reduction: fewer failed prints, optimized design and correct material choice reduce total production cost far more than cheaper filament alone.

We always calculate the total project price including design optimization, material use and expected failure rate. Contact us with your 3D file and a description of the application — we'll find the solution that gives the least waste and the best price.

FAQ — Recycled 3D printing

Can all 3D printing materials be recycled?

All thermoplastics (PLA, PETG, ABS, ASA, TPU, nylon) can in principle be granulated and recycled. Quality drops with each cycle, though. Thermosets like SLA resin can't be recycled by re-melting — the chemical reaction is irreversible.

What is rPETG?

rPETG is PETG filament made from recycled PET plastic (typically bottles or industrial waste). It prints almost identically to virgin PETG and is well suited to functional parts and prototypes where cosmetic finish isn't critical.

Does 3D printing produce a lot of waste?

Compared to CNC machining, 3D printing produces significantly less waste — typically 2-30% versus 60-90% for CNC. The waste mainly comes from support structures and failed prints, both of which can be minimized with experience and design optimization.

Can I recycle my own failed prints?

Yes, with the right equipment. A filament extruder like a Filabot or Artme can turn granulated plastic into new filament. Quality is variable, though, and the investment (DKK 15,000-40,000) mainly makes sense for companies with high print volume.

What's the best way to reduce 3D printing waste?

Design optimization has the biggest impact: correct orientation, minimized support, topology optimization and the right material choice from the start. That's far more effective than trying to recycle waste afterward.

Is 3D printing more sustainable than injection molding?

At low volumes (under 500 parts), 3D printing is typically more sustainable — no tooling required, and only the necessary material is used. At high volumes, injection molding is more efficient per part, but requires tooling with its own resource footprint. The crossover point varies with the part's geometry.

Does Maker Factory offer recycled materials?

We can print in rPETG and rPLA by arrangement. For most projects, though, we recommend focusing on design optimization and correct material choice as the primary sustainability strategy — that delivers a bigger overall reduction in resource use than switching to recycled filament alone.