3D printing & CAD · Beginner

3D printing

Building a real object layer by layer from a 3D model

What is 3D printing?

3D printing is making a physical object from a 3D model by building it up one thin layer at a time. A program called a slicer turns the model into layer instructions, and the printer lays down plastic, resin or metal to match. It is used for prototypes, parts, figurines and more.

Think of it like this

It is like building a loaf of bread from the bottom up, one slice at a time, until the full shape stands on the plate.

Where it fits in a 3D project

  1. Create
  2. Surface
  3. Rig
  4. Animate
  5. Render
  6. Export

Export: Saving and sharing the result: file formats, engines and printing.

How 3D printing works

  1. 01Make or download a watertight 3D model, usually as an STL or 3MF file.
  2. 02Open it in a slicer, which cuts it into layers and adds supports.
  3. 03The slicer writes G-code, the printer’s step-by-step instructions.
  4. 04The printer builds the layers, then you remove supports and finish the part.

3D printing vs CNC machining

Property3D printingCNC machining
ProcessAdds material layer by layerCuts material away from a block
ShapesComplex, hollow, organic formsStrong, precise parts
WasteLittleMore offcuts

Print complex shapes and quick prototypes; machine parts that need maximum strength and precision.

Where 3D printing is used

  • Product prototypes and fit checks
  • Figurines and tabletop miniatures
  • Replacement parts, jigs and tools

Beginner tip

Check the model is watertight, with no holes or flipped faces, before slicing. Most failed prints from downloaded or AI-made models start as mesh errors.

Terms related to 3D printing

3D printing FAQ

What file do I need for 3D printing?
Most printers work from STL or 3MF files, which you open in a slicer. The slicer then exports G-code for the printer. OBJ also works in most slicers.
Can I 3D print an AI-generated model?
Often, yes. Check it is a single closed mesh with no holes, scale it to real size, and let the slicer add supports. Thin details may need thickening to survive printing.
What is the difference between FDM and resin printing?
FDM printers melt plastic filament and are cheap and good for larger parts. Resin printers cure liquid resin with light and give much finer detail, which suits miniatures and jewelry.

Updated October 29, 2026 · Browse all 3D terms