What Is ReFuel? A Transparent Look at 3D-Fuel's Recycled 3D Printing Filament

Sustainability in 3D printing matters - to many of our customers and to us. That’s why we created ReFuel, our recycled filament product line. However, recycled filament isn’t always as simple as “melt it and make it again.” In this post, we want to clearly explain what ReFuel is, how it’s made, and why its appearance can vary from spool to spool.

ReFuel may be produced from several of our materials, including Standard PLA+, Tough Pro PLA+, Pro PETG, and Pro PCTG. Regardless of the base polymer, the underlying recycling principles remain the same.

What ReFuel Is Made From

Today, ReFuel is produced using two primary internal material sources, both generated during normal manufacturing operations.

1. Color Transition Spools

Filament extrusion is a continuous process. When we switch production from one color to another - such as from red to blue - there is an unavoidable transition phase where the filament is neither the original color nor the final target color.

During these transitions, we typically generate several spools that fall outside our strict color standards. While these spools are mechanically sound and fully printable, they don’t meet the visual consistency requirements for our standard product lines.

Rather than discard this material, we reallocate it to ReFuel. The result is a 3D filament with naturally occurring color blends or gradients, the exact appearance of which depends on the materials and colors involved in the transition.

2. Re-Pelletized Internal Scrap

The second source of ReFuel comes from internal scrap generated during quality control. These are spools that may fall outside tolerance for reasons such as:

• Diameter variance

• Cosmetic winding issues

• Other non-performance-related QC failures

These spools are not sold as first-quality filament. Instead, they are re-pelletized using a strand pelletizer and then extruded again into filament that meets our functional and dimensional requirements.

Because this recycled feedstock often contains a wide mix of colors and almost always includes material from multiple production runs, it is not possible to control or predict the final color of the filament.

Why Color Consistency Isn’t Guaranteed

Between color-transition material and mixed re-pelletized scrap, color variability is an inherent characteristic of recycled filament. While ReFuel is produced to be mechanically usable and printable, it is not possible to guarantee a specific or repeatable color from spool to spool.

This variability applies across all ReFuel materials, whether PLA-based or PET-based. While print performance remains the priority, visual consistency is not something recycled feedstock can reliably deliver under these conditions.

What We’re Exploring Next

We are actively evaluating additional post-industrial material streams that could be recycled and pelletized more consistently across multiple polymer families.

Our ideal recycled feedstock would be:

• Clean, post-industrial material

• Consistent in base color (natural, white, or off-white)

• Suitable for controlled color addition

This approach would allow us to maintain the environmental benefits of recycled material while offering improved color consistency across a production run, regardless of the base polymer.

ReFuel vs. Virgin Filament: Setting the Right Expectations

ReFuel is designed for customers who value material reuse and sustainability and are comfortable with visual variability. However, for applications where color consistency, repeatability, and guaranteed availability are critical, virgin material remains the better option.

Using virgin resin enables:

• Predictable production scheduling

• Highly consistent color from batch to batch

• Maximum process repeatability in printing

Both options have a place, and our goal is to be clear about what each is best suited for.

Our Commitment to Transparency

ReFuel is not about cutting corners. It is about responsible reuse, honest communication, and reducing waste without compromising functionality. We believe recycled filament will play an important role in the future of additive manufacturing, and we will continue to refine our processes as better recycling opportunities become available.

If you have feedback, questions, or specific use cases in mind, we welcome the conversation.