What is 3D printing and how does it work?

3D printing is a way of making a real, physical object from a digital design. Instead of carving a shape out of a block or pouring plastic into a mould, a 3D printer adds material one very thin layer at a time until the object is finished. That is why you will also hear it called additive manufacturing.

Step 1: a digital model

Everything starts as a 3D file on a computer — a bit like a very precise digital sculpture. Designers create these in 3D modelling software, and there are also huge online libraries of ready-made models. For the items in our shop, the models are already prepared, so all you choose is the material, color and size.

Step 2: slicing

A printer cannot read a 3D model directly. A program called a slicer cuts the model into hundreds of flat horizontal layers — imagine slicing a loaf of bread — and works out the exact path the printer should follow for each one. The slicer also adds a sparse internal honeycomb (called infill) so parts are strong without being solid plastic all the way through, plus temporary supports for any overhanging bits.

Step 3: printing, layer by layer

The most common type of home and small-shop printer is a filament printer (often called FDM). It feeds a thin plastic strand — the filament — into a heated nozzle, a little like a precise hot-glue gun. The nozzle moves back and forth, drawing the first layer onto a flat build plate. Then it moves up a fraction of a millimetre and draws the next layer on top. Each layer is typically 0.1–0.3 mm thick, so even a small object can be several hundred layers tall.

A second popular type is the resin printer. Instead of melting plastic, it uses a vat of liquid resin that hardens where light shines on it. Resin can capture extremely fine detail, which is why it is great for figurines and miniatures.

Step 4: finishing

When the print is done, supports are removed and the part is checked. Resin prints are also washed and given a final cure under UV light so they are fully hard. Then it is ready to use.

Why does it look "layered"?

Because it is! Look closely at a filament print and you can usually see fine horizontal lines — those are the layers. Thinner layers mean smoother surfaces but longer print times. Resin prints show far fewer visible lines.

That's really all there is to it: a digital design, sliced into layers, built up one layer at a time. Simple idea, surprisingly powerful results.