Print settings
Cold Crabby splits settings three ways, the same way established slicers do. Knowing which tab something is in is most of the battle.
| Tab | Describes | Changes when |
|---|---|---|
| Printer | The machine | You buy a printer or change the nozzle |
| Filament | The spool | You swap material |
| Process | How to print this thing | Every print, potentially |
Each tab has a profile dropdown at the top. Pick a saved profile and every option below it fills in. Managing those profiles is covered in Printers, filaments and profiles.
Can't find something?
Press Ctrl/⌘ + F and type. The search spans all three tabs, so you don't have to guess which one owns it.
The five settings that matter most
If you change nothing else, understand these.
Layer height (Process → Layer) — how thick each slice is. Default 0.2 mm. Smaller means smoother and slower; larger means faster and more visible layer lines. Stay at or below about 75 % of your nozzle diameter.
Walls (Process → Walls) — how many perimeter loops around the outside. Default 3. This, more than infill, is what makes a part feel solid. Going from 2 to 4 walls does more for strength than doubling infill.
Infill density (Process → Infill) — how much material inside. Default 20 %. Decorative parts are fine at 10 %; functional parts want 30–50 %. Above about 50 % you're usually better off adding walls.
Temperatures (Filament → Temperature) — nozzle 210 °C and bed 60 °C by default, which suits typical PLA. Your filament's label wins over any default.
Supports (Process → Support) — off by default. Turn them on when your model has overhangs steeper than about 45°. Check the preview afterwards: supports that touch nothing are wasted plastic and a worse surface.
Everything else, by group
Printer
| Group | What lives there |
|---|---|
| Hardware | Nozzle diameter, bed size and shape, kinematics, gantry clearances, whether the firmware can cancel a single object |
| Retraction | How far and how fast filament is pulled back on travel; Z-hop |
| Output | G-code flavour (Marlin or Klipper), start and end scripts, lifecycle markers |
Filament
| Group | What lives there |
|---|---|
| Temperature | Nozzle and bed, with separate first-layer values |
| Cooling | Fan speeds, minimum layer time |
| Filament G-code | Custom G-code for this material |
Process
| Group | What lives there |
|---|---|
| Layer | Layer height, first-layer height |
| Walls | Wall count, wall generator, thin walls, extra perimeters, ordering, seam behaviour |
| Extrusion | Line widths and flow |
| Infill | Density, pattern, angle |
| Support | On/off, type, density, overhang threshold |
| Speed | Per-role print speeds and travel speed |
| Quality | Bridging, dimensional compensation, other accuracy options |
| Surfaces | Top and bottom solid layer counts, surface fill, ironing |
| Adhesion | Skirt, brim, raft |
| Objects | Print order, G-code run between objects |
| Thumbnail | The preview image embedded in the G-code file |
| Mesh | How the incoming model is interpreted |
Options that only apply in certain configurations hide themselves. Choosing the classic wall generator, for example, reveals options the Arachne generator doesn't use — so the panel never offers you a control that would do nothing.
Infill patterns
| Pattern | Character |
|---|---|
| Rectilinear (default) | Parallel lines, alternating direction each layer. Fastest. |
| Grid | Lines crossing at right angles. Stronger, slower. |
| Honeycomb | Hexagons. Good strength for the material spent. |
| Gyroid | A 3D curve. Equal strength in every direction; nice for flexibles. |
| TPMS-D | Diamond minimal surface. Organic and isotropic. |
Two special modes
Spiral (vase) mode (Process → Walls) prints a single continuous wall that climbs as it goes — no seam, no layer changes. For open, single-walled models only. Turning it on forces the settings it's incompatible with (extra walls, infill, top layers, retraction) off for you, and keeps your bottom layers as the base.
Ironing (Process → Surfaces) makes a second, hot, barely-extruding pass over top surfaces to smooth them. Slow, and only worth it on visible flat tops.
Advanced — tuning the ironing pass
Type chooses what gets swept: every top surface, only the single highest one (much faster on a tall model, and usually the only face anyone sees), or all solid surfaces.
Flow is how much material the pass adds, as a percentage of a normal bead — around 10 % is enough to re-melt the surface without raising it. Spacing is how far apart the passes run; well under a bead width is what flattens the ridges between them. Speed should stay low, because the nozzle needs dwell time to melt what it crosses. Angle defaults to following the layer's own fill direction; set an explicit angle to cross the fill instead, which flattens it more effectively.
Getting parts to the right size
A printer lays a bead slightly wider than asked, so parts come out a little large and holes a little tight. Both are consistent for a given machine, so both can be measured once and corrected (Process → Quality).
XY size compensation grows or shrinks every contour by a fixed amount. Print a test cube, measure it, and set the difference as a negative value if the cube came out oversized. Because the material spreads inward as well as outward, this also tightens holes.
Hole compensation adjusts holes on their own, so a peg that will not fit can be freed without changing the outside of the part.
Both default to off. Start from a measurement, not a guess — and keep the values small; a shrink larger than a thin feature will erase it, which the slice log warns you about.
The flare at the very bottom
Elephant foot compensation fixes a different problem from the two above. The first layer is deliberately squashed into the bed to make it stick, so it spreads sideways and only the base measures oversize — enough that a part won't sit flat, or won't drop into the hole it was designed for. XY size compensation would shrink the whole part to fix the bottom of it.
Measure the bulge with calipers, halve it, and put that in. 0.1–0.2 mm covers most machines. Only the first layer is corrected, because only the first layer is squashed.
It won't eat your first-layer detail
Shrinking the first layer sounds like it should wipe out embossed text and thin logo strokes — that's what a plain shrink does. This one measures how thin the geometry is at each point and simply stops there, so a fine feature keeps its width while the walls around it are corrected in full. It also leaves the base alone where the model already flares outward above it, and skips itself entirely when you print on a raft, where nothing touches the bed.
Advanced — tuning the correction
Elephant foot layers spreads the correction over more than one layer, ramping it to zero. Leave it at 1 unless a large correction leaves a visible step at the second layer.
Minimum contour width is the width the correction will never shrink a feature below. Left at 0 it works this out from your wall width; raise it to protect chunkier detail, lower it for a more literal correction.
First layer height (Process → Extrusion) prints the bottom layer thicker than the rest. The extra material absorbs what mesh bed levelling only approximates, which is why almost every profile sets it. It has no effect when you print on a raft, since the raft takes over contact with the bed.
Where your settings are saved
Changes in this panel apply to the current plate. To make them permanent, save them into a profile — see Printers, filaments and profiles.
Advanced — configuring outside the UI
The CLI and self-hosted server read a layered slicer.toml: built-in defaults, then your user config, then a project slicer.toml in the working directory, then command-line flags. Each layer deep-merges over the last, so a project file only needs the values it changes. See Configuration.