Printing a horizontal filament span across a gap between two anchor points without material below.
Bridging exploits filament tension and rapid cooling to span gaps without drooping. The printer deposits filament under slight tension while the cooling fan immediately solidifies it before gravity acts. Bridge length is limited by filament stiffness, cooling efficiency, and print speed. PLA bridges well up to about 80 mm; flexible filaments bridge poorly.
Enable bridging detection in the slicer. Set bridging speed to 20-40 mm/s and fan to 100%. Orient parts so long spans run parallel to X or Y axis. Use a bridge calibration test print to dial in settings per filament.
Too-slow speed causes excessive sag. Too-fast speed snaps the bridge mid-span. Flexible or nylon filaments bridge poorly: use supports. Bridges over 100 mm require careful flow reduction (5-10%) to avoid build-up at ends.
Related terms: Overhang, Part Cooling, Supports
| Field | 3D printing, 3D design |
|---|---|
| Source | EDi Brain: tech/fdm |
Engineer, author of The Big Book of 3D Printing and additive manufacturing expert