What Is 3D Printing?

3D Printing in Plain English

3D printing is a manufacturing process that builds a physical object layer by layer from a digital file. Instead of cutting material away like traditional machining, a 3D printer adds material, one thin layer at a time, until the full object is complete. That is why it is also called additive manufacturing.

The process starts with a 3D model file, usually an STL or 3MF file, which contains the shape of the object. That file gets processed by software called a slicer, which slices the model into hundreds or thousands of horizontal layers and tells the printer exactly how to move, how much material to use, and at what temperature.

The printer then follows those instructions and builds the object from the ground up, one layer at a time, until it is done.

Quick Facts

• Invented in the 1980s, consumer-affordable since ~2010
• Most home printers use plastic filament (FDM)
• A typical print takes 30 minutes to several hours
• Layer heights typically range from 0.1mm to 0.3mm
• Entry-level printers start around $200
• You can print almost any shape that a computer can model

How Does a 3D Printer Actually Work?

Step 1: The 3D Model

Every print starts with a digital 3D model. You can design your own using software like Fusion 360, Tinkercad, or Blender, or download a ready-made file from a marketplace like Cults3D.

Step 2: Slicing

The model file goes into slicer software such as Bambu Studio, PrusaSlicer, or Cura. The slicer divides the model into layers and generates a G-code file, which is the set of instructions your printer follows.

Step 3: Printing

The printer reads the G-code and starts building. For FDM printers, a heated nozzle melts plastic filament and deposits it in precise paths. Each layer bonds to the one below it as it cools.

Step 4: Post Processing

Once the print finishes, you remove it from the print bed. Depending on the model, you may need to remove support structures, sand rough edges, or paint and assemble parts.

Types of 3D Printing

FDM (Fused Deposition Modeling)

The most common type for home use. A spool of plastic filament (PLA, PETG, ABS, etc.) is melted through a nozzle and deposited layer by layer. Affordable, beginner-friendly, and capable of printing large objects.

Resin (SLA / MSLA)

Uses UV light to cure liquid resin. Produces extremely fine detail, making it popular for miniatures, jewelry, and dental models. Requires more post-processing and ventilation but delivers exceptional quality.

SLS (Selective Laser Sintering)

Uses a laser to fuse powdered material. Strong, functional parts with no support structures needed. More common in industrial and professional settings due to cost.