PET

PET is mostly used in 3D printing as a part of an ecological initiative recycling PET bottles. Most PET filaments will in fact be commercialized as rPET or rePET. Printing with PET is recommended for intermediate users rather than beginners.

Difference between PET vs PETG

PET is a filament made up of the two monomers mentioned earlier. PETG has the same monomers as PET, but it also has an extra monomer called glycol.

The addition of glycol transforms it into a completely new type of plastic, giving it more flexibility and reducing the amount of moisture it absorbs.

You might be wondering why glycol is needed when PET is already a fantastic filament. PET, as good as it is as a filament, is not without flaws. One of them is the hazing effect it has when heated. PETG contains glycol, which helps to eliminate the hazing effect. In addition, due to crystallization effects, normal PET filaments can become bristly. Adding the glycol softens the exterior of the final printout and makes it easier to grip.

To put things in perspective, PET filaments are used when you want a printout that is not soft to the touch but rather rough around the edges and rigid. If you want a flexible finish, however, PETG is the way to go.

Another significant difference between PET and PETG is how the finished product is finished. While PET prints are significantly more durable than PETG prints, they are also more susceptible to breakage.  PET, unlike PETG, is more susceptible to breaking when used for 3D printing due to its higher stress tolerance. This simply means PETG is more resistant to impact than PET.  Furthermore, PET is much more hygroscopic than PETG, which means it absorbs a lot more moisture from the air. You shouldn't leave any filament in a humid environment, but some filaments are particularly more vulnerable than others.

Printability of PET filament

An enclosed build chamber is recommended for printing PET, and a heated build chamber is preferred. The build surface should be free of direct and grease, which can be cleaned with ethanol or acetone before applying any adhesion promoters, such as Magigoo, 3D-Lac, or glue.

Browse all PET filaments in stock in our warehouse in Senec, Slovakia. For comparison, see also PETG and ECO.