What Is 3D Printing and How Does It Work?

3D printing (also called additive manufacturing) turns a digital 3D model into a physical object by building it layer by layer. Instead of cutting material away from a block, as in milling, the printer adds material only where it is needed.

How FDM 3D printing works

The most widespread technology is FDM (fused deposition modelling), which is what we use:

3D model. It all starts with a file — usually STL or 3MF — describing the shape of the part.
Slicing. A program called a slicer “cuts” the model into hundreds of thin horizontal layers and works out the nozzle path for each. This is also where the exact print time and material amount come from.
Printing. The printer melts plastic filament at about 200–260 °C and lays it down through a fine nozzle, layer after layer, until the part is done.
Finishing. Temporary supports are removed (if any), and the part can be sanded, primed or painted when needed.

What can be printed

Functional parts: stands, holders, brackets, enclosures, jigs
Spare parts that are no longer sold
Prototypes to check shape and fit
Small batches without moulds
Models, mock-ups, figures, gifts and decor

Which materials

FDM prints with thermoplastics. The most used are PLA (easy and precise), PETG (tough all-rounder), ABS (heat resistant) and ASA (for outdoors). When to pick which is in the materials comparison.

When 3D printing is the better choice

3D printing pays off when you need few pieces, a complex shape or a fast turnaround. There is no mould, so one piece isn’t disproportionately expensive, and a design change is just a new file. For tens of thousands of identical parts, injection moulding usually wins on unit price.

How accurate is 3D printing

Modern FDM printers print layers of about 0.1–0.3 mm and are accurate enough for functional parts, assemblies and prototypes. The surface has a slight layer texture that can be smoothed when needed.

How to try it

You don’t need your own printer. Upload an STL or 3MF model and see the price instantly — more in how to order a 3D print.