Part1: What is 3D Printing?
Every 3D printer builds with the same basic principle, taking a digital model from your device and printing it 3D by adding a single layer at a time. Additive Manufacturing is the term used when referring to this type of manufacturing process.
3D printing & additive manufacturing technologies have been around for years now but we are finally hitting a point in time where the technology is available at the right cost to make this a viable manufacturing process. Subtractive manufacturing process exist in form factor like mills, lathes and water/plasma cutters. Each of these processes take a digital model from your device and cut/subtract material until the final model is revealed.
What are the benefits of 3D Printing:
- Complex geometry with models come at little to no extra cost
- Customization of each part or model
- Ability to prototype at a low-cost
- Quick turn-around on prototype or low run parts
- Large range of materials available
Limitations of 3D Printing:
- Lower strength & anisotropic material properties
- Less cost-competitive at higher volumes
- Limited accuracy & tolerances
- Post-processing & support removal
There are many types of 3D printing and depending on the outcome required, some are more viable than others. For the time being we will concentrate on the following types of printing
Fused Deposition Model (FDM) Printers:
- FDM printers are the most widely available to consumers
- Each layer is produced by melting "filament" through a heated nozzle
- Materials can be sturdy/flexible plastics or infused plastics with carbon and now some metals. Infused or harder materials do require upgrades on most consumer printers
- These printers are generally cheap to run & maintain
- Downsides are they can be tricky to configure depending on the material
- Lot's of moving parts which can creates more calibration & ultimately troubleshooting
Stereolithography (SLA) Printers:
- SLA printers are becoming more available to consumers
- SLA printers utilize resin in a vat or tub with a clear bottom
- The vat has a LCD screen on the bottom that projects the image up into the resin as a build plate in the vat or resin rises over time to cure each layer
- Less moving parts than traditional FDM printers but can be challenging to level the build plate to the screen properly
- Produce higher quality parts due to screen being able to provide high resolution
- Resin is a liquid and can be harmful and messy compared to FDM printing
- Resin printers are more expensive to run & maintain
- LCD screens need to be replaced from time to time & vats require the clear film to be replaced periodically
- Most resin prints require to be post processed by being cured in a UV light
Selective Laser Sintering (SLS) Printers:
- SLS printers are mainly used in industrial level productions
- This process involves have a powder that is melted together with a laser
- After the part has been printed, there is usually a post processing of heat cycle the part to give it the final strength and bond
- Large & expensive machines reserved for higher production volumes at commercial/industrial levels. Materials include metals at this time