What are supports in 3D printing?

Supports are auxiliary structures the slicer adds under overhanging parts of the model. They prevent collapse during printing and are broken off or removed after completion. Modern slicers offer tree, normal and organic types.

When you need them

Slicer has an overhang angle (typically 45°). If the model slopes below this angle, the printer can't cool filament fast enough and it sags. Above 45° = need supports. Below 45° = bridging.

Types

Normal / Linear - classic pillars
Tree supports - organic shape, less material
Organic (Bambu, Orca) - AI-generated, most efficient
Everywhere vs. Touching build plate - anywhere or only from plate

How to remove

With FDM, supports break off by hand or pliers. Clean residues with knife, file, dremel. For perfect surface under supports: dissolvable PVA on second extruder.