Tutorial 21: Opening Arc Vase
Create a vase that starts as a half-circle opening at the base and gradually closes to nearly complete at the top. The Arc block draws partial circles, and by driving its sweep angle with normZ, you create a form that breathes and encloses space as it rises.
What you'll learn
- How to use the Arc block (center, radius, start angle, arc angle)
- How to drive Arc Angle dynamically with Map Range and
normZ - How partial circles create dramatic open-form vases
- How For Z with Travel Z gives manual layer control
Prerequisites
- Completion of Tutorial 2 (Spiral Vase with Dynamic Radius) is recommended.
Step 1: Define variables
Step 1
Create four slider variables
Add four Set Variable blocks with Show in Viewport enabled:
- vaseRadius =
25— arc radius
Step 2: Add For Z
For Z
Interactive preview is available in the interactive reader.
Step 2
Add Translate and For Z
Add Translate (center on bed). Inside the body, add For Z with Z Start = Layer Height, Z End = vaseHeight, Step = Layer Height.
Step 3: Add Arc with dynamic sweep
Arc
Interactive preview is available in the interactive reader.
Step 3
Add Arc with Map Range driven sweep angle
Inside the For Z body, add an Arc block with:
- Direction = counter-clockwise
After the Arc (via next), add Travel Relative Z = Layer Height.
Complete block program
Full program — Tutorial 21
Interactive preview is available in the interactive reader.
Final block structure
| # | Block | Where | Values |
|---|---|---|---|
| 1–4 | Set Variable | Path Group | vaseRadius=25, vaseHeight=50, startArc=180, endArc=350 |
| 5 | Translate | Path Group | X = bedsize_x/2, Y = bedsize_y/2 |
| 6 | ↳ For Z | Inside Translate | Start = LH, End = vaseHeight, Step = LH |
| 7 | Arc | Inside For Z | Radius, Start Angle=0, Arc Angle = mapRange(normZ) |
| 8 | Travel Rel Z | After Arc | Z = Layer Height |
Outcome
You should see a vase that starts as a wide opening (semicircle) at the base and gradually closes to a near-complete circle at the top. The shrinking gap creates a dramatic aperture effect.
Load this tutorial
Interactive preview is available in the interactive reader.
Interactive preview is available in the interactive reader.
What's Next
Tutorial 22: Nested Polygon Mandala — Use For Range with a loop variable to create concentric rotated hexagons — a geometric mandala stacked into a vase.