Ramming speed (hotend change)
How much plastic per second comes out during ramming before swapping hotend. −1 uses the max volumetric speed.
How it works
Before switching extruder (printers with two nozzles, like the H2D) or hotend (printers that swap it on their own, like the H2C), the nozzle does a “ramming”: it pushes out a stretch of filament so it doesn't ooze while it waits. On printers with a single extruder and a single hotend, like the A1, these settings do nothing.
When to change it
- With a single extruder (like the A1): don't touch it; it has no effect.
Typical values
| Value | What for |
|---|---|
| −1 | PLA Basic, the maxdefault |
Watch out for
- If your printer does switch extruder or hotend and you see strings or leftovers of the previous filament right after the switch, this is the group of settings to look at.
Goes well with
What Bambu Studio saysits help card, quoted
What Bambu Studio says
The maximum volumetric speed for ramming before a hotend change, where -1 means using the maximum volumetric speed.
Bambu Studio tooltip for this setting · AGPL-3.0
Read more at the official source
In your profileBambu PLA Basic @BBL A1 · -1 mm³/s
In Bambu Studio, the profile Bambu PLA Basic @BBL A1 sets it to-1 mm³/s
Using another slicer? Look for the idea, not the name: in Orca Slicer almost everything has the same name; in PrusaSlicer or Cura it may be called something else, or not exist.