OpenSCAD Automation Skill#

Version: 1.1.0

Author: Klepeto 🦞

Description: Direct OpenSCAD scripting, rendering automation, and library integration

---

What is OpenSCAD?#

OpenSCAD is a free, open-source "Programmer's Solid 3D CAD Modeller". Instead of interactive modeling like Fusion 360 or Tinkercad, you write code that describes objects. The script is compiled into a 3D model.

Why OpenSCAD?#

• 📐 Parametric designs - Change one variable, entire model updates
• 🔧 Precise dimensions - Perfect for mechanical parts, enclosures, adapters
• 📦 Version control friendly - .scad files are plain text, diffable in Git
• ⚙️ Mathematical shapes - Gears, threads, spirals, organic forms via code
• 🎨 Generative art - Algorithms creating complex patterns
• 🔄 Reusable libraries - Import community libraries for common parts

When to Use OpenSCAD vs Other CAD#

Use OpenSCADUse Fusion 360 / TinkercadParametric designsOrganic, freeform shapesPrecise mechanical partsQuick prototypingMathematical surfacesVisual, interactive designBatch generationOne-off modelsVersion-controlled designsVisual iteration

Get OpenSCAD: https://openscad.org (Windows, macOS, Linux)

---

Installation#

Windows#

1. Install OpenSCAD: Download from https://openscad.org
   • Default location: ????\OpenSCAD\openscad.exe
2. OpenClaw Workspace: ????\.openclaw\workspace

macOS#

bash

brew install openscad

Linux#

bash

# Ubuntu/Debian
sudo apt install openscad

# Fedora
sudo dnf install openscad

OpenClaw Path: ~/.openclaw/workspace

Verify Installation#

bash

# Windows PowerShell
& "????\OpenSCAD\openscad.exe" --version

# macOS/Linux
openscad --version

Expected output: OpenSCAD version 2021.01 (or newer)

---

Capabilities#

• ✅ Write .scad files directly to workspace
• ✅ Render to STL (3D printing)
• ✅ Render to PNG (previews)
• ✅ Render to SVG (2D projections)
• ✅ Execute OpenSCAD CLI with proper PowerShell syntax
• ✅ Provide parametric templates
• ✅ Batch render multiple variants
• ✅ Use community libraries (BOSL, NopSCADlib, etc.)
• ✅ Generate customizers with // comments

---

Language Reference#

Basic Syntax#

openscad

// Variables
width = 50;
height = 30;
depth = 20;

// Primitive solids
cube([width, height, depth], center = true);
sphere(r = 10);
cylinder(h = 30, r = 5);

// Transformations
translate([x, y, z]) { ... }
rotate([x, y, z]) { ... }  // degrees
scale([x, y, z]) { ... }

// Boolean operations
union() { ... }      // combine
difference() { ... } // subtract
intersection() { ... } // keep overlap

Special Variables (Resolution)#

openscad

$fn = 100;    // Number of fragments (circles)
$fa = 5;      // Minimum angle
$fs = 0.5;    // Minimum size

Tip: Higher $fn = smoother curves, slower render. Default is 12.

Control Flow#

openscad

// Conditionals
if (width > 50) {
    cube(20);
} else {
    sphere(10);
}

// Loops
for (i = [0:5]) {
    translate([i * 10, 0, 0])
        cube(5);
}

// List comprehensions
sizes = [for (i = [1:10]) i * 2];

Modules and Functions#

openscad

// Module (creates geometry)
module box(w, h, d) {
    cube([w, h, d], center = true);
}

box(50, 30, 20);

// Function (returns value)
function diameter(pitch, teeth) = pitch * teeth / PI;

gear_d = diameter(2, 20);

Import/Export#

openscad

// Import STL, OFF, AMF, 3MF
import("part.stl");

// Import DXF, SVG (2D)
import("profile.dxf");

// Export via CLI (not in script)
// & openscad.exe -o output.stl input.scad

Modifier Characters#

openscad

* cube(10);    // Disable (comment out)
! sphere(10);  // Show only (root)
# cylinder(10); // Highlight (debug, red)
% cube(10);    // Background (transparent)

---

Cheat Sheet (Quick Reference)#

2D Primitives#

openscad

circle(r = 10 | d = 20);
square(size = 10, center = true);
square([w, h], center = true);
polygon([[x1,y1], [x2,y2], ...]);
text("Hello", size = 10, font = "Arial");

3D Primitives#

openscad

sphere(r = 10 | d = 20);
cube(size = 10, center = true);
cube([w, d, h], center = true);
cylinder(h = 30, r = 5 | d = 10, center = true);
cylinder(h = 30, r1 = 5, r2 = 3, center = true); // cone
polyhedron(points = [...], faces = [...]);

Extrusions#

openscad

linear_extrude(height = 10, twist = 45, slices = 20) {
    circle(10);
}

rotate_extrude(angle = 360) {
    translate([10, 0]) circle(2);
}

Transformations#

openscad

translate([x, y, z]) { ... }
rotate([x, y, z]) { ... }  // degrees around each axis
rotate(a, [x, y, z]) { ... }  // rotate a degrees around vector
scale([x, y, z]) { ... }
resize([x, y, z], auto = true) { ... }
mirror([x, y, z]) { ... }
color("red") { ... }
color("#FF0000") { ... }
color([1, 0, 0, 1]) { ... }  // RGBA 0-1

Boolean Operations#

openscad

union() {
    cube(10);
    sphere(10);
}

difference() {
    cube(20);
    sphere(10);  // subtracted from cube
}

intersection() {
    cube(20);
    sphere(10);  // only overlapping volume
}

Mathematical Functions#

openscad

abs(x)      // absolute value
sin(x)      // sine (degrees)
cos(x)      // cosine
tan(x)      // tangent
acos(x)     // arccosine
asin(x)     // arcsine
atan2(y, x) // arctangent
floor(x)    // round down
ceil(x)     // round up
round(x)    // round nearest
sqrt(x)     // square root
pow(x, y)   // x^y
ln(x)       // natural log
log(x)      // base-10 log
min(a, b)   // minimum
max(a, b)   // maximum
norm(v)     // vector norm
cross(a, b) // cross product

String Functions#

openscad

str("Value: ", 42)      // concatenate
chr(65)                  // character from code (A)
ord("A")                 // code from character (65)
len("hello")             // length (5)

Type Tests#

openscad

is_undef(x)    // is undefined
is_bool(x)     // is boolean
is_num(x)      // is number
is_string(x)   // is string
is_list(x)     // is list/vector
is_function(x) // is function

---

Command-Line Usage#

Render to STL (3D Printing)#

powershell

& "????\OpenSCAD\openscad.exe" -o "output.stl" "model.scad"

Render to PNG (Preview)#

powershell

& "????\OpenSCAD\openscad.exe" -o "preview.png" --imgsize 1024,1024 "model.scad"

Render to SVG (2D Projection)#

powershell

& "????\OpenSCAD\openscad.exe" -o "output.svg" --projection both "model.scad"

With Parameters#

powershell

& "????\OpenSCAD\openscad.exe" -o "out.stl" -D "width=50" -D "height=30" "parametric.scad"

Open in GUI#

powershell

& "????\OpenSCAD\openscad.exe" "model.scad"

Common CLI Options#

OptionDescription-o <file>Output file (STL, PNG, SVG, etc.)-D <var name="val">Set variable before rendering--imgsize W,HPNG image size--projection [both]SVG projection type--renderForce full CGAL render--enable <feature>Enable experimental features--viewallFit model in view (PNG)--colorscheme <name>Color theme (starnight, beforedawn, etc.)

---

Community Libraries#

OpenSCAD has a rich ecosystem of community libraries. Import them with use <library.scad> or include <library.scad>.

General Purpose Libraries#

BOSL2 (Belfry OpenSCAD Library v2)

Best for: Everyday modeling helpers, shapes, masks

openscad

use <BOSL2/std.scad>
use <BOSL2/rounding.scad>

rounded_cube([50,30,20], r=5);

• GitHub: https://github.com/BelfrySCAD/BOSL2
• Wiki: https://github.com/BelfrySCAD/BOSL2/wiki
• License: BSD-2-Clause

NopSCADlib

Best for: 3D printer parts, electronics enclosures, hardware

openscad

use <NopSCADlib/screws.scad>
use <NopSCADlib/enclosures.scad>

screw_hole(3);  // M3 screw hole

• GitHub: https://github.com/nophead/NopSCADlib
• License: GPL-3.0-or-later

UB.scad

Best for: 3D printing workflow, mechanical parts, view helpers

openscad

use <UB.scad/UB.scad>

view_rotate();  // Animation helpers

• GitHub: https://github.com/UBaer21/UB.scad
• License: CC0-1.0

dotSCAD

Best for: Mathematical modeling, reduced complexity

openscad

use <dotSCAD/modeling.scad>
use <dotSCAD/math.scad>

• GitHub: https://github.com/JustinSDK/dotSCAD
• Docs: https://openhome.cc/eGossip/OpenSCAD/
• License: LGPL-3.0-only

Specialized Libraries#

threads.scad

Best for: Metric threads, bolts, nuts, augers

openscad

use <threads.scad>

metric_bolt(d=10, pitch=1.5, length=50);
metric_nut(d=10);

• GitHub: https://github.com/rcolyer/threads-scad
• License: CC0-1.0

Round-Anything

Best for: Filleted/rounded parts, ergonomic design

openscad

use <round-anything.scad>

round_anything(pts, radius);

• GitHub: https://github.com/Irev-Dev/Round-Anything
• Docs: https://learn.cadhub.xyz/docs/round-anything/overview/
• License: MIT

YAPP Box

Best for: Electronics project boxes with PCB mount

openscad

use <YAPP_Box.scad>

// Define PCB dimensions, generate enclosure

• GitHub: https://github.com/mrWheel/YAPP_Box
• License: MIT

Board Game Toolkit

Best for: Board game organizers, boxes, inserts

openscad

use <boardgame_toolkit.scad>

box_with_lid(w, h, d);

• GitHub: https://github.com/pinkfish/openscad_boardgame_toolkit
• License: Apache 2.0

STEMFIE

Best for: Educational construction sets, compatible parts

openscad

use <stemfie.scad>

stemfie_beam(length);
stemfie_plate(width, height);

• GitHub: https://github.com/Cantareus/Stemfie_OpenSCAD
• Project: https://www.stemfie.org/
• License: GPL-3.0-or-later

Installing Libraries#

1. Download .scad files from GitHub

2. Place in your OpenSCAD libraries folder:

   • Windows: ????\Documents\OpenSCAD\libraries\
   • macOS: ~/Documents/OpenSCAD/libraries/
   • Linux: ~/.local/share/OpenSCAD/libraries/

3. Import in your scripts: openscad

   use <BOSL2/std.scad>
   
   

---

Templates#

Basic Cube#

openscad

// cube.scad
cube([20, 20, 20], center = true);

Parametric Box with Lid#

openscad

// box_with_lid.scad
width = 80;
height = 60;
depth = 40;
wall = 2;
lip = 1;

// Box base
difference() {
    cube([width, height, depth], center = true);
    translate([0, 0, lip])
        cube([width - wall*2, height - wall*2, depth], center = true);
}

// Lid
translate([0, 0, depth/2 + lip])
    cube([width, height, 5], center = true);

Gear (Simple)#

openscad

// gear.scad
$fn = 100;
teeth = 20;
module_gear = 2;  // module (tooth size)

pitch_diameter = teeth * module_gear;
outer_diameter = pitch_diameter + 2 * module_gear;

difference() {
    cylinder(h = 10, d = outer_diameter);
    cylinder(h = 12, d = pitch_diameter * 0.4);  // shaft hole
}

Enclosure with Screw Bosses#

openscad

// enclosure.scad
use <NopSCADlib/screws.scad>

width = 100;
height = 80;
depth = 30;
wall = 2;

// Outer box
difference() {
    cube([width, height, depth], center = true);
    translate([0, 0, 1])
        cube([width - wall*2, height - wall*2, depth], center = true);
}

// Screw bosses (M3)
boss_positions = [[-40, -30], [40, -30], [-40, 30], [40, 30]];
for (pos = boss_positions) {
    translate([pos[0], pos[1], -depth/2])
        screw_hole(3, l = depth);
}

Phone Stand#

openscad

// phone_stand.scad
$fn = 100;

// Base
cube([80, 60, 5], center = true);

// Back support (angled)
rotate([20, 0, 0])
    translate([0, -20, 30])
        cube([60, 10, 50], center = true);

// Front lip
translate([0, 25, 10])
    cube([60, 5, 15], center = true);

---

Workflow#

1. Design#

Tell the agent what you want:

"Create a parametric phone stand adjustable for 60-80mm phones"

Agent writes .scad file to workspace.

2. Preview#

powershell

& "????\OpenSCAD\openscad.exe" -o "preview.png" --imgsize 1024,1024 "design.scad"

3. Export for Printing#

powershell

& "????\OpenSCAD\openscad.exe" -o "design.stl" "design.scad"

4. Iterate#

"Make the angle 15° instead of 20°, add cable slot"

Agent modifies parameters, re-render.

---

Tips & Best Practices#

Performance#

• Use $fn wisely: 50-100 for visible curves, 12-24 for hidden features
• Simplify early: Remove unnecessary details before final render
• Test small: Preview with low resolution, render high-res only when ready

Design#

• center = true: Makes positioning easier
• Use variables: All dimensions as variables for easy tweaking
• Comment parameters: // [10:100:10] creates Customizer sliders
• Modular design: Break complex models into modules

3D Printing#

• Wall thickness: Minimum 2-3x nozzle diameter (0.8-1.2mm for 0.4mm nozzle)
• Tolerances: Add 0.2-0.3mm clearance for moving parts
• Orientation: Design for optimal print orientation (minimize supports)
• Export as STL: Binary STL is smaller than ASCII

Debugging#

openscad

// Highlight problematic part
# translate([0, 0, 10])
    cube(20);

// Disable temporarily
* sphere(10);

// Show only this part
! cylinder(20);

// Debug output
echo("Width =", width);

---

Error Handling#

ErrorCauseSolutionUnexpected tokenPowerShell syntaxUse & before quoted pathFile not foundWrong pathCheck relative path from workspaceCGAL errorNon-manifold geometryCheck for holes, intersections, inverted normalsNo top level objectEmpty scriptAdd at least one primitiveToo many pointsExcessive $fnReduce resolutionImport failedMissing fileVerify file exists and path is correctCircular dependencyModules calling each otherRestructure code

---

Learning Resources#

Official Documentation#

• Website: https://openscad.org
• User Manual: https://en.wikibooks.org/wiki/OpenSCAD_User_Manual
• Language Reference: https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/The_OpenSCAD_Language_Reference
• Cheat Sheet: https://openscad.org/cheatsheet/index.html

Tutorials#

• Wikibooks Tutorial: https://en.wikibooks.org/wiki/OpenSCAD_Tutorial
  • Chapter 1: Getting started
  • Chapter 2: Scaling and parameterizing
  • Chapter 3: Combining objects
  • Chapter 4: Modules
  • Chapter 5: Libraries
  • Chapter 6: Control flow
  • Chapter 7: Loops and patterns
  • Chapter 8: Extrusion
  • Chapter 9: Math and geometry

Community#

• Forum: https://forum.openscad.org
• GitHub: https://github.com/openscad/openscad
• Thingiverse: Search "OpenSCAD" for examples
• Printables: Parametric models section

---

Integration with Other Tools#

Fusion 360#

• OpenSCAD: Parametric, mathematical, programmatic
• Fusion 360: Interactive, visual, assemblies
• Workflow: Export STL from OpenSCAD → Import to Fusion 360 for assembly

Slicers (PrusaSlicer, Cura)#

• Direct STL import from OpenSCAD output
• Parametric workflow: Adjust OpenSCAD variables → Re-slice → Print

Git / Version Control#

• .scad files are plain text - perfect for Git
• Track design iterations
• Branch for variants
• Diff to see what changed

---

Created: 2026-05-24 | Updated: 2026-05-24 (v1.1.0 - Added full documentation, libraries, cheat sheet)

Klepeto 🦞