3D printing of plastics is broadly categorized into 3 main categories based on the raw materials they use- Filament (FDM/FFF), Resin (SLA, mSLA, LCD, DLP etc), and Powder (SLS).
Filament printers use thermoplastic filaments (usually PLA, ABS, PETG and other speciality filaments such as PEEK, TPU, composite filaments etc) which are fed through to a heated nozzle and extruded onto a build plate layer by layer to create a 3 dimensional object. Typically the nozzle first makes an outline of the shape and thin fills in the middle of the piece with material allowing for different levels of hollow parts.
Resin printers use thermoset liquid resins (all of which have their own proprietary formulations) which are exposed to a light source (laser/ projector/ LCD screen) layer by layer to create a 3 dimensional object. In the case of a laser, it traces the shape of the layer that is being printed, while in the case of a projector or screen, the entire layer is exposed at a single time. The thin layer of liquid that is exposed to the source of light hardens and creates the solid plastic part.
Powder printers use thermoplastic powders (typically nylon) which are sintered together using a high strength laser. The particles of plastic exposed to the laser as it moves around fuse together due to the heat and subsequent layers of plastic are fused to the previous layer creating a 3 dimensional shape.
The following table compares each process-
Features |
Filament |
Resin |
Powder |
Speed |
Slow |
Fast |
Medium |
Accuracy |
Medium |
High |
Medium |
Post processing |
Medium (Supports, sanding) |
High (Supports, Cleaning, UV) |
Low (No supports, dusting, sanding) |
Finish |
Poor |
Excellent |
Medium |
Choice of materials |
Medium |
Medium |
Low |
Economies of scale |
Low |
Medium |
Medium |
Machine Cost |
Low |
Low |
High |
Material Cost |
Low |
Medium-High |
High |
Ease of use |
Easy |
Difficult |
Difficult |
Most people purchase a filament based 3D printer to start with due to its ease of use and choice of inexpensive raw materials.
Resin printers are more applicable for users who need fine details, high accuracy, excellent surface finish, high speed and some economies of scale.
Powder printers are more applicable for users who need to produce larger parts, cannot afford to have support structures, and need some economies of scale.
Please contact us if you have any specific requirements- we would be happy to help you!