Bambu Studio ironing settings for smooth flat tops

Short answer

Ironing makes the nozzle pass over the top surface again, barely extruding, which flattens the tool marks into a smooth finish. In Bambu Studio set Ironing type to Top surfaces (Process → Quality → Ironing) for flat plaques, signs and coasters, and pair it with an Aligned seam. Leave it off for curved tops, silk PLA and carbon-fiber filament.

Why it happens

A flat top is printed as rows of lines, and light catches every ridge between them. On plaques and signs the top is the part people look at, so the pattern shows.

Ironing adds one slow pass over the top layer only. On curved tops there is no flat area to smooth, so it just adds time.

The settings in Bambu Studio

Names are from Bambu Studio 2.x. The settings search box finds either the name or the key.

Good to know

What Plateright checks

The report checks how much of each object is flat top surface and turns ironing on only for the objects that benefit, not the whole plate.

Questions

Does ironing add a lot of print time?

It adds one extra pass over top surfaces only. On a flat plaque that is noticeable but modest; on models without big flat tops Plateright leaves ironing off.

Should I iron every print?

No. Ironing only helps large flat tops. On curved or sloped tops it adds time with no visible benefit.

Why does my ironed surface still show lines?

Usually the top layer is too thin, or the ironing flow is too low for your filament. Check the top layers in Preview and try your filament profile’s default ironing flow first.

Related fixes

Updated September 28, 2026.