What is 3D printing?
3D printing builds an object one thin layer at a time, straight from a 3D design file. There's no mould or cutting tool to make first, so it's ideal for one-off items, prototypes, replacement parts, and small batches.
You don't need your own printer or design skills. A local shop can print your file, help you choose a material, and even design the part for you from a sketch, a photo, or a broken original.
The main ways parts are printed
Shops use a few different kinds of printer. You don't have to choose one yourself (your shop will suggest the right one), but it helps to know the basics.
| What it's called | How it works, in plain words | Best for | Cost |
|---|---|---|---|
| Filament printing (FDM) | Melts a plastic strand and draws each layer, like a very precise hot glue gun | Everyday parts, prototypes, larger items, most household jobs | Lowest |
| Resin printing (SLA, MSLA, DLP) | Hardens liquid resin with light, one thin layer at a time | Tiny detail and smooth surfaces: miniatures, figurines, jewellery models | Low |
| Powder printing (SLS, MJF) | Fuses fine nylon powder with a laser or heat, in batches | Strong, finished-quality parts and runs of many identical parts | Higher |
| Metal printing | Fuses metal powder into solid metal parts | Strong or complex metal parts for industry | Highest |
Most jobs start with filament printing: it's the most common and the most affordable. Choose resin when fine detail matters most.
How getting something printed works
- Bring your idea or your file. A 3D file (such as STL or 3MF), a sketch, a photo, or the broken part you want to replace.
- Talk it through. Tell the shop what the part is for: indoors or outdoors, how strong it needs to be, what it should look like. They'll suggest a material and process.
- Get a quote. The price depends mostly on the part's size, the material, and how long it takes to print.
- Get it made. Pick it up or have it shipped. You pay the shop directly.
Not sure which material? Start with choosing a material by what you're making, or just describe your project to a shop.
The jargon, explained
| Term | What it means |
|---|---|
| FDM / FFF | Filament printing: melted plastic, layer by layer. The most common kind of 3D printing. |
| SLA, MSLA, DLP | Types of resin printing: liquid resin hardened by light. Very fine detail. |
| SLS, MJF | Powder printing: nylon powder fused by a laser or heat. Strong, finished-quality parts. |
| PLA | The most common filament: cheap, easy, comes in every colour. Not for heat or outdoors. |
| PLA+ | A tougher version of PLA that's less likely to snap. |
| PETG | A tougher everyday filament that handles water and some heat. |
| ABS / ASA | Tough filaments that handle heat. ASA also handles sun and weather. |
| TPU | A soft, rubbery filament for flexible parts like phone cases and seals. |
| Nylon (PA) | A very tough, slightly slippery plastic for gears, hinges, and working parts. |
| Carbon fibre-filled / glass fibre-filled | Plastic mixed with short fibres, making parts much stiffer. |
| STL, 3MF, OBJ, STEP | Common 3D file types. STL and 3MF are what most shops print from. |
| CAD | Computer-aided design: the software used to design parts. Many shops offer CAD design if you don't have a file. |
| Layer height | How thin each printed layer is. Thinner layers look smoother but take longer. |
| Infill | The pattern inside a printed part. More infill means a stronger, heavier part. |
| Supports | Temporary scaffolding printed under overhangs, removed afterwards. |