How Does 3D Printing With Pellets Work?

The classic FDM 3D printing process consists of creating layers by depositing a molten material, usually in the form of plastic filament. Recently, however, a new way to use this manufacturing technology is emerging, moving away from coils to the use of pellets or granules. Pellet 3D printing is a 3D printing method that uses thermoplastics in the form of pellets to manufacture parts layer by layer. More and more companies are developing machines that work with this type of material, or even solutions adaptable to standard 3D printers to make them compatible with pellets.

Plastic pellets are granular materials obtained through what is known as pelletizing. In the process, the materials, which can be chemicals, plastics, composites or minerals, are molded into the compressed form of pellets. These types of resources are mainly used for injection molding, although, as we have mentioned, they are becoming increasingly evident in the world of 3D printing. As it turns out, their use in additive manufacturing is somewhat low compared to the number of filament spools that exist today. Though this may seem paradoxical, since filaments are made from pellets, and using the pellets directly in printing would save an intermediate step in the entire process.

Pellet extruder developed by Tumaker (photo credits: 3Dnatives)

Pellets and 3D printing

One thing to keep in mind is that pellets and filaments require different extruders to suit your printing needs. In contrast to filaments, pellet extruders have an integral bowl, which gradually absorbs the materials and pushes them into the melting zone. There, the pellets are softened to the desired consistency, after which the plastic is ejected through the nozzle and deposited on the printing platform. Although the process may seem a bit more complex compared to filament extrusion, it has a number of really interesting benefits that we will see below.