The Most Common Types of 3D Printing

Have you ever used 3D Printing to produce plastic parts?

There are many types of 3D printing used for plastic parts, but the three most common are:

1. FDM - Fused Deposition Modelling

2. SLA - Stereolithography

3. SLS - Selective Laser Sintering

Each of these three methods has different strengths and weaknesses, which should be considered when choosing the type of printing for your intended project.

FDM - Fusion Deposition Modelling

This type of printing extrudes thermoplastic filament through a heated nozzle, building up the model layer by layer.

It is perhaps the most common type of printing, as these machines are affordable, have a small footprint, and are readily available for purchase. Many types of plastic can be used for FDM printing, such as PLA, ABS, and PETG.

The downsides are that FDM printers can only print with moderate detail, the surface finish is not ideal and the part strength is lower due to the thermal
bonding between the layers.

SLA - Stereolithography

SLA printing uses a UV laser to cure liquid resin into solid layers.

This method produces extremely detailed parts with a smooth surface finish, making it perfect for high-precision prototypes, jewellery moulds, and investment casting moulds.

While the parts are extremely detailed, they can be brittle. For this reason, SLA-printed parts are not suitable for applications where long-term durability or high impact resistance is required.

SLS - Selective Laser Sintering

This type of 3D printing uses a high-powered laser to fuse powdered plastic material into solid layers in a process known as sintering.

SLS printing is used to create functional, durable parts such as hinges or enclosures. The heat from the laser creates a strong bond between the layers, giving strength in all directions.

Startup costs for SLS printing are high - SLS printing machines can be expensive and the raw materials costs are higher in comparison to other printing methods. Printed parts can also have a rougher surface which may require post-processing if a smoother surface is needed.