In short
- The extruder feeds the filament, the hotend melts it and the nozzle, usually 0.4 mm, lays down the paths.
- A slicer splits the model into layers and works out print time. That's what our quote prices are based on.
- The most common printing problems are warping, stringing and a weak first layer.
Below we explain the terms that come up most often in 3D printing. Some of them link to longer guides. We start with what a printer is made of.
A–E
ABS – a plastic that handles impacts and temperatures up to about 95 °C. It's printed in a closed chamber.
ASA – similar to ABS, but it resists sun and rain. Good for things mounted outdoors.
Bridge – a section printed in mid-air between two supported points. Short bridges print without supports.
Brim – a thin layer around the model that helps it stick to the bed. There's more in the guide to printing problems.
Direct drive – an extruder mounted right above the hotend. The filament has a short path, which makes printing flexible TPU easier.
Enclosure (chamber) – a closed space around the printer that keeps the heat in. Needed for ABS, ASA and nylon.
Extruder – a mechanism with toothed wheels that pushes the filament into the hotend.
F–L
FDM (FFF) – printing by laying down molten plastic layer by layer. This is the technology we use.
Filament – plastic in the form of a line, usually 1.75 mm thick, wound on a spool.
First layer – the layer the whole print depends on. It has to stick well to the bed.
G-code – a file with instructions for the printer: head moves, temperatures and speeds. The slicer creates it.
Gyroid – a wavy infill pattern that is equally strong in every direction. We compare patterns in the guide to print strength.
Hardened nozzle – a nozzle made of wear-resistant steel. Needed for carbon fibre filaments.
HDT (heat deflection temperature) – the temperature at which a print starts to soften under load. For PLA it's about 55 °C.
Hotend – the part of the head that melts the filament and feeds it to the nozzle.
Infill – the open structure inside a print, usually 15–20%.
Layer height – the thickness of one layer, usually 0.1–0.3 mm. Thinner layers give a smoother surface, but printing takes longer.
N–R
Nozzle – the tip of the hotend that the molten filament comes out of. Usually 0.4 mm across.
Overhang – a part of the model sticking out sideways over empty space. Up to about 45° it usually prints without supports.
PEI – a plastic used to coat bed plates. It holds the first layer well, and a cooled print comes off easily.
PETG – a strong, water-resistant filament. It handles temperatures up to about 70 °C.
PLA – the most popular filament. It's accurate and cheap, but it softens from about 55 °C.
Retraction – pulling the filament back before a travel move over empty space so it doesn't ooze from the nozzle.
S–Z
Slicer – software that splits the model into layers, plans the paths and works out print time and filament use. That's how our quote calculates prices.
Spiral vase mode – printing in one continuous spiral line, with no seam. It's used for vases and plant pot covers.
Spool – a reel of wound filament, usually 1 kg.
STL, 3MF, OBJ – 3D model file formats. We accept all three. 3MF also stores units and colours.
Stringing – thin hairs between parts of a print. It's usually caused by damp filament, as we explain in the guide to drying.
Supports – temporary structures under overhangs that are removed after printing. They raise the price, as we show in the guide to printing costs.
TPU – a flexible filament that bends like rubber.
Wall (perimeter) – the outer paths of each layer. They do the most to make a print strong.
Warping – the corners of a print lifting as the cooling plastic shrinks.
Z offset – a correction of the nozzle's distance from the bed for the first layer.
We describe the materials in more detail on the PLA, PETG, ABS, ASA, TPU and PA6-CF pages. If a term is missing, write to us and we'll add it.
Test yourself
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