Small perimeter speed
How fast small outlines, usually holes, are printed. It's a percentage of the outer wall speed: in a circle a few millimeters across there's no room to speed up.
How it works
A 4 mm hole is a loop about 12 mm long. At 200 mm/s the print head doesn't even reach that speed before it has to brake, and the constant speeding up and slowing down distorts the outline: the hole comes out oval with a bump at the seam. Printing them at 50% keeps them round.
What counts as “small” is set by “Small perimeter threshold”; at 0, the slicer decides on its own. It can also be given in mm/s instead of a percentage.
When to change it
- A part with holes for screws or a shaft that come out oval: lower it to 30–40%.
- A part with no small holes, like a solid figure: it changes nothing.
Typical values
| Value | What for |
|---|---|
| 30% | Very round holes; a bit slower |
| 50% | Defaultdefault |
| 100% | Same as the outer wall |
Watch out for
- 0 means automatic, not “stop”.
- On parts with hundreds of small holes the print time goes up; that's the price of getting them round.
Goes well with
What Bambu Studio saysits help card, quoted
What Bambu Studio says
This setting will affect the speed of perimeters having radius <= small perimeter threshold(usually holes). If expressed as percentage (for example: 80%) it will be calculated onthe outer wall speed setting above. Set to zero for auto.
Bambu Studio tooltip for this setting · AGPL-3.0
Read more at the official source
In your profile0.20mm Standard @BBL A1 · 50%
In Bambu Studio, the profile 0.20mm Standard @BBL A1 sets it to50%
In other slicers
- Orca Slicer
- Small perimetersSpeed › Other layers speed
- PrusaSlicer
- Small perimetersSpeed › Speed for print movesIn Prusa the % is of the perimeter speed and the threshold is fixed (a radius of 6.5 mm or less).
- Cura
- Small Feature SpeedExperimentalIn Cura it's a % of the normal speed, not a value in mm/s.
Names taken from each program's code (Orca Slicer 2.4.2, PrusaSlicer 2.9.6, Cura 5.13.0). Credits