Updated script: 2026-04-22

• See script for changes

A fully parametric car cup holder adapter fully human designed in Blender and then converted to an OpenSCAD script using AI assistance to make it user customizable.

This adapter securely fits into your vehicle’s cup holder and grips cups or bottles using flexible fingers—no supports required, no guesswork sizing. You simply measure your vehicle's cup holder and your cup or bottle, enter the numbers, and print.

✅ Key Features

✅ Fully parametric (measurement‑driven)
✅ Smooth tapered fit for car cup holders
✅ Upper section with three flexible fingers
✅ Stress‑relieved finger roots (no cracking over time)
✅ Easy insertion with chamfered finger tips
✅ Prints upright, no supports

📏 What You Need to Measure

You only need four real‑world measurements:

Vehicle cup holder

• Inside diameter at the bottom

• Inside diameter at the rim

• Height from bottom to rim

Cup / bottle

• Diameter at the point where the cup should be gripped

Enter these values at the top of the .scad file or in the CUSTOMIZER settings—nothing else needs to be changed.

🧠 How the Design Works

Lower Section (Vehicle Fit)

A smooth tapered cone that matches your vehicle’s cup holder
Uses friction and taper rather than clips
Compatible with a wide range of vehicles

Transition

An 45‑degree chamfer between the lower and upper sections
Improves strength, printability, and appearance

Upper Section (Grip)

Three fingers evenly spaced around the cup
Bottom portion is a solid ring for strength
Upper portion flexes to grip cups and bottles

🖨 Print Recommendations

Material: PETG (strongly recommended)
Layer height: 0.2 mm
Perimeters: 3–4
Infill: 15–25% (gyroid or cubic)
Supports: None
Orientation: Print upright, as modeled

Sample image details:

Printer: Elegoo Centauri Carbon
Filament: Polymaker PolyLite PETG (old formula)
Perimeters: 3
Infill: 15% gyroid

🧩 Customization Notes

The model is intentionally user friendly: only measurement inputs are needed.
Wall thickness, finger stiffness, and geometry are tuned automatically.
Advanced users can modify parameters, but doing so may affect strength or reliability.

OpenSCAD

If you don't want to install OpenSCAD, you can use one of the web-based versions:

https://ochafik.com/openscad/ - OpenSCAD Playground

https://openscad.cloud/ - OpenSCAD Cloud

Steps to Generate an STL File Using OpenSCAD Playground

1. Open the OpenSCAD Script

• Locate the .scad file you downloaded.

• Open the file in any text editor (such as Notepad, VS Code, TextEdit) or directly in your web browser.

2. Copy the Script Contents

• Select all text in the file:

  • Windows/Linux: Ctrl + A

  • Mac: Cmd + A

• Copy the selected text:

  • Windows/Linux: Ctrl + C

  • Mac: Cmd + C

3. Open OpenSCAD Playground

• Open the OpenSCAD Playground by navigating to the URL linked above in your web browser.

4. Paste the Script into OpenSCAD Playground

• Click inside the Script text box on the webpage.

• Select all existing text in that box:

  • Windows/Linux: Ctrl + A

  • Mac: Cmd + A

• Paste the copied script:

  • Windows/Linux: Ctrl + V

  • Mac: Cmd + V

• (Alternatively, you can delete the existing text first, then paste.)

5. Review the Automatically Rendered Model

• The 3D model should automatically render after pasting.

• Rotate or zoom the preview to visually inspect the model.

6. Enable Customization Controls

• At the top of the webpage, locate the toolbar buttons.

• Click Edit to hide the script panel.

• Click Customize to display the customization panel.

7. Adjust Measurements

• In the Measurements section of the customization panel:

  • Modify the four input values as needed.

  • Changes may update the preview automatically.

8. Render the Final Model

• Click the Render button in the lower-left corner of the page.

• Rendering may take a moment, depending on model complexity.

9. Download the STL File

• Once rendering is complete, the button text will change to Download STL.

• Click it to download the file.

• The file will be named export.stl (or export (1).stl, export (2).stl, etc., if a file with that name already exists).

10. Use the STL File

• Open the downloaded STL file in your slicer software of choice (such as Orca, Cura, PrusaSlicer, or Bambu Studio).

• The file is now ready for printing or further processing.

AI note: The original model design was created entirely by me in Blender. I only used AI assistance to help convert that model into a parameterized OpenSCAD script, providing it with the STL file, screenshots from multiple angles, and my design goals. I then iterated through approximately fifteen versions of the script to achieve the correct rendering and to adjust the design for constraints inherent to OpenSCAD’s modeling approach. All photos are screenshots from modeling tools, screenshots from slicing tools, and/or actual photos of printed results.