Filaments vs Pellets: Which Type of Plastic to Choose for 3D Printing?

Plastics are without doubt one of the most widely used material families in additive manufacturing. Compatible with a wide variety of processes, they offer multiple properties and characteristics to parts, whether those are destined to be prototypes, tooling or end-use objects. Available in many forms – filaments, pellets, powders, resins – they meet the needs and requirements of manufacturers in all sectors. While we compared powders to plastic resins a few months ago, it’s time to take a look at two other polymer families: filaments and pellets. What are their characteristics and applications? Which 3D printing processes are they compatible with? What manufacturers are on the market, and how much do these materials cost? We tell you all about it in this new dedicated article!

Filaments and pellets are two forms of material currently compatible with 3D printing, and although metallic and ceramic solutions are available today, we’ll be concentrating solely on plastics. First of all, we need to go back over the definition of a plastic pellet and a plastic filament. A pellet is a kind of small ball 0.5 cm in diameter that can be melted, molded or extruded to make all kinds of plastic objects. Plastic pellets are therefore key in the chemical industry. They can be used in additive manufacturing with specific machines.

To make filament for 3D printers, you need plastic pellets (photo credits: Capifil)

Filament, on the other hand, is a thermoplastic obtained by mixing plastic pellets or ground plastic scrap with several additives. A filament extruder is required to achieve the tube-like appearance. After several stages of cooling, the filament passes through a coiling machine to obtain a spool that can then be used by a 3D printer.