Outer wall acceleration (outer_wall_acceleration)
Outer wall acceleration is a number in mm/s². Bambu Studio, OrcaSlicer and Creality Print accept 0 mm/s² or more; PrusaSlicer and Cura declare no range.
What does each slicer call it?
Five slicers, five spellings of one setting. The scope column is which preset the key belongs to, which is what decides whether changing it follows the printer, the filament, or the print profile.
| Slicer | Key | Scope |
|---|---|---|
| PrusaSlicer | external_perimeter_acceleration |
process |
| Bambu Studio | outer_wall_acceleration |
process |
| OrcaSlicer | outer_wall_acceleration |
process |
| Cura | acceleration_wall_0 |
process |
| Creality Print | outer_wall_acceleration |
process |
What does each slicer say about it?
Each slicer offers its own values, so each gets its own line.
- PrusaSlicer: Acceleration in mm/s² for outer walls. 0 uses the regular wall acceleration.
- Bambu Studio: Acceleration for outer walls, in mm/s². Lower values give smoother surfaces and less ringing.
- OrcaSlicer: Acceleration for the outer wall in mm/s². Lower values reduce ringing and give cleaner visible surfaces.
- Cura: Acceleration for the outer wall, in mm/s². Lower it for a cleaner visible surface.
- Creality Print: How fast the head speeds up on the outer wall, in mm/s². Lower values reduce ringing on the visible surface.
Where does it live in the file?
All five slicers file this under the process preset, so its value follows the print profile rather than the model. A .3mf is a zip, so unzip it and search for external_perimeter_acceleration, outer_wall_acceleration and acceleration_wall_0, or open the file in preslice and read the Raw tab, which searches every member at once.
Four of the five slicers write their settings into a sidecar part beside the geometry. Cura writes them into the model XML itself, so there is no config part to open.
| Slicer | Part | Format |
|---|---|---|
| PrusaSlicer | Metadata/Slic3r_PE.config |
INI, one key = value per line |
| Bambu Studio | Metadata/project_settings.config |
JSON, one flat object |
| OrcaSlicer | Metadata/project_settings.config |
JSON, one flat object |
| Cura | 3D/3dmodel.model |
XML metadata inside the model part, under a cura namespace |
| Creality Print | Metadata/project_settings.config |
JSON, one flat object |
What values are valid?
Each slicer declares its own type, default, and bounds for its key. They do not always agree, and where they disagree the file is still valid in both: the slicer that wrote it is the one that enforced its own rule.
| Slicer | Type | Unit | Default | Range |
|---|---|---|---|---|
| PrusaSlicer | float | mm/s² | 0 |
not declared |
| Bambu Studio | floats | mm/s² | not declared | 0 or more |
| OrcaSlicer | float | mm/s² | not declared | 0 or more |
| Cura | float | mm/s² | 3000 |
not declared |
| Creality Print | float | mm/s² | 500 |
0 or more |
PrusaSlicer and Cura declare no range for this key, so nothing in the file bounds it.
The slicers disagree on the type: PrusaSlicer, OrcaSlicer, Cura and Creality Print as float, Bambu Studio as floats. preslice reads all of them.
Every type, default, and bound above is read from the slicer's own field definitions rather than from measurement: PrusaSlicer's PrintConfig.cpp, Bambu Studio's PrintConfig.cpp, OrcaSlicer's PrintConfig.cpp, Cura's fdmprinter.def.json and Creality Print's PrintConfig.cpp.
Can I read it from my own file?
Yes, without installing a slicer. Open preslice and drop a .3mf on the page. It unzips and parses the file in your browser, and shows outer wall acceleration under its own name alongside the rest of the print settings. The file stays in your browser; see what leaves it.