Mastering your 3D Printer means being able to think like a 3D Printer: each part is a vertical stack of varied layers, not a solid object. It’s tempting to design your parts like you would for a CNC Mill, but using subtractive manufacturing methodologies on an additive manufacturing device such as a 3D Printer will lead to a steeper learning curve.
This article discusses the differences between subtractive and additive manufacturing so you can build your knowledge base on 3D printing from the ground up.
If manufacturing methods like milling and laser cutting were a photograph, additive processes like 3D printing would be the photo-negative. Instead of cutting away material to reveal a 3D object, 3D printing adds material to a foundation until an object is created. Since 3D printing runs contrary to how engineers normally manufacture new items, it is important to review 3D printing fundamentals.
Most 3D printers are called “Filament Deposition Manufacturing” (AKA FDM) machines that extrude plastic in layers that later fuse together into a solid object. That fusing process is called “Fused Filament Fabrication” or FFF for short.
FDM printers are designed for manufacturing small- to medium-scale batches of prototypes or functional designs like tooling and fixtures. This is because FFF is not as skilled at creating high-tolerance parts when compared to subtractive methods like CNC milling.
A product layer is created when a 3D printer nozzle deposits melted material in a set, flat “XY” pattern. Extrusion deposits can be controlled many ways: speed, amount layered per second, thickness, to achieve your desired geometry.
While single layers are made of an “XY” material pattern, whole 3D parts are simply a series of layers fused together in the “Z” direction. Like traditional CNC machines, 3D printers are controlled by coordinates in this XYZ space. When you design a 3D part, it is important to think of it as a stacked series of melted material. Operating a 3D printer also involves considering printing overhangs and preventing rough surface finish.