How to Enable Ironing in PrusaSlicer

To enable ironing in PrusaSlicer, open Print Settings > Infill and tick Ironing. The type, flow, and spacing options appear below the checkbox. If you do not see it, switch the mode toggle in the top-right corner to Expert. Ironing runs a smoothing pass over top surfaces to remove gaps and give a clean, flat finish.

Turn it on

1. Set the mode toggle (top right) to Expert.
2. Open Print Settings > Infill.
3. Tick Ironing.

Choose the type

The Ironing Type dropdown controls how much gets ironed:

• Topmost surface only: irons just the final visible layer. The usual choice, and the least added time.
• All top surfaces: irons every top-facing layer, including recessed ones.
• All solid surfaces: irons the most and is rarely worth the time.

Flow and spacing

Start from the defaults and adjust in small steps:

• Ironing flow (around 15 percent): how much material the pass extrudes. Raise it if the surface looks under-filled, lower it if it looks over-extruded.
• Ironing spacing (around 0.1 mm): the gap between ironing lines. Tighter spacing is smoother but slower.

Why this matters for a print farm

Ironing is a finish setting that defines how a product looks, so it needs to be identical on every unit. It also adds time, which matters when you multiply it across a run, so it is a deliberate tradeoff to set once and reuse.

Printago sets the ironing pass once at the profile level and applies it fleet-wide, so the smoother top surface, and the time it costs, stay consistent and predictable across a production run. See cloud slicing and how to set up a 3D print farm.