Graduate

Material science 101

3D printing materials are generally thermoplastics which means they can be reworked and reshaped on application of heat without degrading them. They vary in properties which would make one material more suited to an application than the others.

To simplify things, below is a side by side comparison of the two materials we specialize in.

PETG

(Polyethylene Terephthalate-Glycol)

PETG is a tough material and will flex elastically, then deform plastically rather than snapping.

Comes in neutral colors such as white and gray with descent surface detail.

Very strong with high impact resistance resulting from its flexibility.

High alkali, acid and water resistance just like big brother PET as used in food and drink containers.

High temperature resistance softening at around 80c.

PLA

(Polylactic Acid)

PLA doesn't like to bend, and puts up a descent fight until failure by breakage.

Superb surface detail with vibrant true colors, highly desirable properties for art.

Rigid but brittle material with respectable strength.

Made from biodegradable materials hence Eco friendly but less resistant to solvents and other chemicals.

Low glass transition temperature of around 60c which is a good thing for high surface detail.

PETG

(Polyethylene Terephthalate-Glycol)

PLA

(Polylactic Acid)

Flexibility PETG is a tough material and will flex, then deform plastically rather than snapping. PLA doesn't like to bend, and puts up a descent fight until failure by breakage.
Finish Comes in neutral colors such as white and gray with descent surface detail. PLA doesn't like to bend, and puts up a descent fight until failure by breakage.
Strength Strong with high impact resistance resulting from its flexibility. PLA doesn't like to bend, and puts up a descent fight until failure by breakage.
Resistance High alkali, acid and water resistance just like big brother PET as used in food and drink containers. PLA doesn't like to bend, and puts up a descent fight until failure by breakage.
Heat High temperature resistance softening at around 80c. PLA doesn't like to bend, and puts up a descent fight until failure by breakage.

To sum it up...

If your print is a vital mechanical part which will be undergoing significant loading or exposed to harsh environmental conditions, then PETG is definitely the material to choose.

Artistically oriented objects or even mechanical but with minimal loads are however more suited to PLA.

Introducing... ThermoPlastic Polyurethane

Better known by its acronym, TPU completes our 3D printing trio.

TPU is essentially a plastic with rubber like characteristics which distinguishes it from the more common PLA and PETG. It can be stretched and reverts to its original form without deformation, it is also more resistant to abrasion.

You can use TPU to print parts that need to bend or flex, extend or contract as part of normal operation, or during installation. This opens up a host of new possibilities such as ergonomic covers for mechanical handles, or mounting brackets that need to absorb vibrations to reduce noise.

One thing worth mentioning, the overall flexibility of the final part can be vastly controlled by the infill density used when printing. For example a cube with lower infill will be squishy in the hand while a completely solid cube will be a lot firmer.