Key takeaways
- Vase mode raises Z continuously while printing a single perimeter. There's no layer change, so there's no seam up the side — except in the bottom layers.
- Enabling vase mode isn't the same as setting "1 perimeter, 0 % infill, 0 top layers" yourself. Prusa Research says plainly that doing it by hand still prints layer by layer, not continuously.
- The model must be a solid, with a single outline at every height. Overhangs, separate branches or holes through the wall fail, because one perimeter can't travel through them.
- A thicker, tighter wall comes from a wider extrusion or a bigger nozzle. Prusa suggests widening the external perimeter, for example from 0.45 to 0.6 mm.
A 20 cm vase printed the normal way spends hours on two or three perimeters, infill and top layers — when all you want is the outside. Vase mode drops everything else: the printer lays a single line of plastic, circling and rising at the same time, from the base to the rim. It's much faster, much lighter, and the body has no seam at all.
The price is that the part is exactly one extrusion line thick. Knowing that limit is the difference between a lovely lampshade and a tangle of filament on the bed.
What vase mode does differently
In a normal print, every outer-wall layer has a start and an end: the printer finishes the loop, raises Z one layer, and starts the next loop. That spot leaves a seam — Prusa Research calls it a "scar" running up the side, and a weak point too. Vase mode has no layer change: Z rises gradually through the whole print, so apart from the first N solid bottom layers there is no point where anything starts or stops. Read 24/10/2026. See sources.
| Setting | PrusaSlicer | Bambu Studio |
|---|---|---|
| Where to enable | Print Settings → Layers and perimeters → Spiral vase | Others → Special mode → Spiral vase |
| Perimeters | 1 | 1 |
| Infill | 0 % | 0 % |
| Top layers | Disabled | 0 |
| Supports | Disabled | — |
| Several objects on one bed | One object only; use Sequential printing for more | Choose the By object print sequence |
| Smoothing the layer join | — | Smooth Spiral (since Bambu Studio 1.9.0) |
Which models work in vase mode
The rule is simple: at every height, the model's cross-section must be one single closed outline. The printer has one continuous line; it can't jump to a second branch and come back.
- The model must be solid. Prusa Research says to define the model as a solid with outside dimensions only. If you model a hollow vase with a 2 mm wall, the slicer tries to make both inner and outer surfaces and fails.
- No separate branches. A handle standing off the body, two towers side by side — at that height the cross-section has two outlines, and vase mode can only print one. Bambu Lab illustrates exactly this case: the part a single perimeter can't reach is left hanging in the air.
- Overhangs are limited. With no supports and one line, the body can only flare out within your printer's and material's overhang limit — see the thresholds in designing parts for FDM.
- No holes through the wall. A hole in the side cuts the outline into two pieces at those layers.
If a downloaded vase STL is already hollow, fill it into a solid before slicing.
Making the wall thicker, stronger and tighter
You can't add perimeters — vase mode has exactly one. What you can change is how wide that one is:
Three ways to thicken a vase-mode wall
- Wider outer-perimeter extrusion
- Prusa suggests raising External perimeters extrusion width, for example from 0.45 to 0.6 mm, for a thicker, stronger, watertight wall
- Bigger nozzle
- A 0.6 or 0.8 mm nozzle gives a much wider line; Prusa recommends 0.8 mm for vase-mode prints in PVB
- More bottom layers
- Bottom solid layers stay adjustable; a thicker base stands steadier and leaks less at the bottom
A bigger nozzle is the most effective of the three, because it both thickens the wall and prints faster. Nozzle sizes and materials are covered in brass vs hardened steel nozzles.
The faint seam that's left, and Smooth Spiral
On models whose surface isn't round enough, the join between the end of one turn and the start of the next can still show as a seam-like streak. Bambu Studio added Smooth Spiral in version 1.9.0: the slicer fits that transition into an arc. The maximum XY smoothing threshold is a percentage of nozzle diameter — 200 % on a 0.4 mm nozzle is 0.8 mm.
Bambu Lab also notes the side effect: the seam goes away but small bumps can appear on the surface. So Smooth Spiral suits vases with smooth surface transitions better than vases with sharp edges.
Choosing a material for vase mode
| Material | Good for | Watch out for |
|---|---|---|
| PLA, PLA Silk | Decorative vases, indoor planters, lamp shells | Easiest to print, and silk looks superb in vase mode; softens with heat — LED bulbs only in lampshades |
| PETG | Translucent lampshades, vases that take light knocks | Tougher than PLA so thin walls crack less; strings when wet — dry it first |
| PVB | Transparent pieces to be smoothed with IPA | Prusa recommends vase mode with a 0.8 mm nozzle: more perimeters leave layers visible even after IPA smoothing |
| TPU | Soft shells, sleeves | Works but slowly; a single wall is very floppy |
Lampshades are the most popular use and the easiest to get wrong: incandescent and halogen bulbs give off enough heat to soften PLA and PETG. In vase mode — a wall one line thick — the part deforms sooner than a solid print would. Use LED bulbs only, with plenty of air between bulb and shade.
Five steps to a first vase
- 01
Check the model
Solid, closed, one outline at every height. If the file is an already-hollow vase, fill it in first.
- 02
Enable vase mode — don't set it by hand
PrusaSlicer: Layers and perimeters → Spiral vase. Bambu Studio and OrcaSlicer: Others → Special mode → Spiral vase. Let the slicer set the related settings.
- 03
Set the wall thickness
Widen the outer-perimeter extrusion, or switch to a 0.6–0.8 mm nozzle. Choose the number of bottom layers.
- 04
Scrub the preview bottom to top
Drag the layer slider through the full height. Anywhere the outline breaks or splits in two is where the print will fail.
- 05
Print and watch the first turns after the base
That's where the spiral starts. If the wall has holes or pits, check flow and filament moisture — with a single line, flow errors show immediately. The calibration order is in calibrate your printer per spool.
Vase mode trades strength for speed and surface. It's a tool for shells, not for parts that carry load.
Frequently asked
What is vase mode?
A mode that prints a model's outer wall as one continuous line, raising Z gradually in a spiral instead of stepping layer by layer. Apart from the bottom layers, the part has no seam. The slicer sets one perimeter, no infill and no top layers. PrusaSlicer calls it Spiral vase; Cura calls it Spiralize Outer Contour.
Where is vase mode in Bambu Studio?
In the Others tab, under Special mode, choose Spiral vase. Bambu Studio then sets one wall, no top layers and 0 % infill. To print several objects on one plate in vase mode, choose the By object print sequence.
Why does my vase-mode print have holes or hanging bits?
Usually because the model has a spot a single perimeter can't travel through: a separate branch, a handle, a hole through the wall, or too steep an overhang. Or the model was already hollow — vase mode needs a solid model with outside dimensions only.
How do I make a vase-mode wall thicker and stronger?
Widen the outer-perimeter extrusion — Prusa Research gives 0.45 to 0.6 mm as an example — or use a 0.6 or 0.8 mm nozzle. Vase mode always has exactly one perimeter, so thickness comes from line width.
Can a vase-mode vase hold water?
A thick enough wall can hold water for flowers, but nothing guarantees it, so test first. And watertight doesn't mean food-safe: the gaps between layers still harbour bacteria.
Can I print several vases at once in vase mode?
Yes, but one after another. PrusaSlicer allows only one object in vase mode unless Sequential printing is on; Bambu Studio needs the By object print sequence. Leave enough space so the toolhead doesn't hit finished vases.