Sub-top surface pattern
The pattern of the solid layer right under the top surface. With “Monotonic” the top comes out smoother, because the lines underneath don't show through.
How it works
The top surface is printed on top of a solid layer. If that layer has lines that change direction and meet at joints, melted plastic builds up at those joints and leaves marks that show through the top, especially on large tops with holes.
With “Monotonic” every line in that layer is printed in the same direction and in order, with no joints going against the grain, and the top comes out even. The pattern applies to the whole solid area of that layer that the top surface reaches, not only the bit directly beneath it. The rest of the internal solid infill stays rectilinear, because it's faster.
When to change it
- Leave it on “Monotonic”; that's the factory setting.
- The lid of a large box or a name plate shows marks coming through: check that it's still on “Monotonic”.
- If the marks are still there with “Monotonic”, the pattern isn't the problem: check the flow (how much plastic comes out) or play in the printer's moving parts.
Typical values
| Value | What for |
|---|---|
| Monotonic | Default; smoother topdefault |
| Rectilinear | A bit faster; may mark the top |
Watch out for
- It only affects one layer; adding top layers doesn't make it thicker.
- It doesn't apply if the top surface is very small or when the layer below is a bridge.
Goes well with
What Bambu Studio saysits help card, quoted
What Bambu Studio says
Line pattern of the solid layer that supports a visible top surface. Its lines can print through and mark the top, so a monotonic pattern gives the smoothest result. The whole solid area that a top surface reaches uses this pattern, not only the part directly beneath it.
Bambu Studio tooltip for this setting · AGPL-3.0
Read more at the official source
In your profile0.20mm Standard @BBL A1 · Monotonic
In Bambu Studio, the profile 0.20mm Standard @BBL A1 sets it toMonotonic
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.