How to Add a Raft in PrusaSlicer

To add a raft in PrusaSlicer, open Print Settings > Support material and set Raft layers to a number above 0. Two or three layers is typical. You do not need supports enabled for a raft; the Raft layers setting works on its own. If the field is hidden, switch the mode toggle in the top-right corner to Advanced or Expert.

Add the raft

1. Switch the mode toggle (top right) to Advanced or Expert so support options are visible.
2. Open the Print Settings tab.
3. Go to the Support material section.
4. Set Raft layers to 2 or 3.
5. Slice. A raft now prints under the whole model.

Raft layers is separate from Generate support material, so you can add a raft without turning on supports anywhere else on the part.

Tune the release

The most common raft complaint is that it fuses to the print. The setting that controls this is Raft contact Z distance in the same Support material section: it sets the gap between the top of the raft and the first model layer. Increase it in small steps until the raft peels off cleanly. Too large a gap and the first layer starts to sag, so move gradually.

Raft, brim, or skirt?

All three print around or under the model, but they solve different problems, and picking the wrong one wastes filament without fixing anything:

Feature	What it does	Best for	Filament cost
Skirt	A loose outline near the model, not touching it	Priming the nozzle and checking bed level before the print	Minimal
Brim	A flat ring fused to the base of the model	Adhesion on flat-bottomed parts and stopping corner lift	Low
Raft	A full multi-layer foundation under the model	Small, spiky, or uneven contact areas, or an uneven bed	High

Reach for a brim first when adhesion is the only issue. Use a raft when the model barely contacts the bed, when corners lift despite a brim, or when the bed surface itself needs help.

Raft settings reference

The raft controls all live in Print Settings > Support material. The two that matter most are Raft layers (how much foundation) and Raft contact Z distance (how easily it releases):

Setting	What it does	Starting point
Raft layers	Number of raft layers under the model	2 to 3
First layer density	How solid the base raft layer is	90% for a strong foundation
Raft contact Z distance	Gap between raft top and the model's first layer	Raise if the raft will not separate
Raft expansion	How far the raft extends past the model footprint	1.5 mm suits most parts

Change one value at a time and print a small test so you can see the effect of each before committing to a long print.

Why this matters for a print farm

A raft is part of a part's adhesion recipe, and that recipe has to survive from the prototype to every production run. Once a model slices reliably with the right raft layers and release gap, re-deriving it by hand on each machine is exactly the drift a farm cannot afford.

Printago stores that recipe with the part and applies it automatically wherever the job routes, so first-layer reliability does not depend on which operator sliced it. See material intelligence for how per-material settings travel with a job, and the PrusaSlicer overview for the rest of the slicer.