Filament › Cooling› Part cooling fanenable_overhang_bridge_fan
Force cooling for overhangs and bridges
Raises the fan when the nozzle prints something in the air, so it hardens before it sags.
How it works
An overhang or a bridge has nothing underneath to hold it while it cools. With this option, on those sections the fan goes up to “Fan speed for overhang” (100% in PLA Basic), even if the rest of the layer gets less air.
What counts as an overhang is decided by the “Cooling overhang threshold”, an advanced setting.
When to change it
- For almost everything: on (default).
- ABS or ASA cracking right at the overhangs: try turning it off or lowering that speed.
Typical values
| Value | What for |
|---|---|
| On | Defaultdefault |
| Off | Materials that don't want air |
Watch out for
- If overhangs still droop with this on, check the nozzle temperature and the overhang speed (Process tab).
Goes well with
What Bambu Studio saysits help card, quoted
What Bambu Studio says
Enable this option to optimize part cooling fan speed for overhang and bridge to get better cooling
Bambu Studio tooltip for this setting · AGPL-3.0
Read more at the official source
In your profileBambu PLA Basic @BBL A1 · Yes
In Bambu Studio, the profile Bambu PLA Basic @BBL A1 sets it toYes
Helps with
In other slicers
- Orca Slicer
- Force cooling for overhangs and bridgesCooling › Part cooling fan
- PrusaSlicer
- Enable dynamic fan speedsCooling › Dynamic fan speedsIn Prusa it only turns on the overhang fan; bridges always use bridge_fan_speed.
- Cura
- No clear equivalent.
Names taken from each program's code (Orca Slicer 2.4.2, PrusaSlicer 2.9.6, Cura 5.13.0). Credits