Hey Steven,
There are many good answers in this thread, but I wanted to provide an oversimplified, long-winded, general overview.
Here’s the flow for printing a part:
- Design part
- Export part as an STL
- Process the STL in a slicer. This will produce GCODE, a simple text language that tells the 3D printer where to move and how quickly.
- Send the GCODE to the 3D printer. At the 'Space, we use Octoprint to send GCODE to the PolyPrinters.
Choosing the software for design can get a bit nebulous.
Generally, 3D design software falls into two categories: solid and shell modeling.
Solid modeling is most often used for mechanical applications, and includes SolidWorks, Fusion360, Inventor, Catia, FreeCAD, and similar. Some of these allow for parametric modeling, which makes it incredibly easy to retroactively edit your geometry. In a solid modeling program, you’ll edit shapes directly - the software uses shape objects. Create a cylinder in a solid modeler, and the application understands it’s a circle extruded to a particular height. Solid modeling programs will allow you to export a STEP file, which is an ISO standard file format for describing geometry in terms of shape objects. I’d use this for complex mechanical assembly, where you might need precise measurements, the ability to resize objects easily, and you’re not aiming for significant superficial detail (such as wrinkles on a person’s face).
Shell modeling is typically used for non-mechanical geometry and animation, and may also be called “mesh modeling”. Blender, ZBrush, and Maya, 3ds Max are examples here. Typically, this sort of modeling software represents surfaces with triangles, NURBS, or similar shapes, instead of shape objects. Internally, mesh/surface/boundary modeling software represents shapes by approximating them with triangles, curves, or other concepts. If you create a cylinder in this sort of program, it’ll be represented as a bunch of triangles, splines, etc., but not as a “cylinder”. I’d use this if I wanted to make an animated 3D movie, sculpt complex organic shapes, or other high-detail work that doesn’t require precise measurement or easy resizing. This type of modeling software likely won’t allow you to export a STEP file.
There are some complications to this explanation. For example, Fusion360 is primarily a solid modeling tool, but does have a surface modeling module. Also, you can use mesh modeling to model mechanical things, or solid modeling to sculpt complex organic geometry, but doing so may be more difficult.
Pretty much all 3D modeling software can export an STL file, which has become the standard for 3D printing. There are a few backronyms for STL, but I like “Standard Tessellation Language”. This is a triangle mesh that approximates the geometry of your design in CAD software. For example, if you create a circle in a solid modeler, then export it as an STL and zoom in, you’ll notice the circle is not truly a circle, but hundreds or thousands of straight line segments.
Pretty much all slicers will accept an STL file and generate GCODE for the printer. However, there are now several different flavors of GCODE, so it’s important to verify your slicer will export a flavor of GCODE compatible with your printer. Kiss Slicer at the 'Space is configured to export the correct flavor of GCODE for the PolyPrinters.