Description
This project combines a 3D printed phone case with an Archimedes screw lift and a marble run. Tilt your phone to move the ball through the track and back up the lift for another lap.
This design was created as a fun engineering project and YouTube build, not as a polished commercial product. Many people asked for the files, so I’ve decided to make them available.
Important
Please note that this is an experimental design.
- Designed specifically for the iPhone 13 Pro.
- The marble run works, but not perfectly.
- The phone must be held at a fairly specific angle.
- Ball bearings can get stuck quite easily.
- If you’re looking for a fun mechanical build and like to tweak things, you’ll probably enjoy it. If you’re expecting a flawless consumer product, this project is probably not for you.
What’s Included
- Printable STL files
- Original FreeCAD project file
- CNC/laser cutting files for the front panel
The CAD model can be edited in FreeCAD. The design was created with functionality in mind rather than perfect CAD practices, so don’t be surprised if some features are a little rough around the edges.
Materials Required
- 19 × M2 × 8 mm screws
- 12 × 6 mm steel ball bearings
- Super glue
- 2 mm acrylic sheet for the front panel (or similar material)
Front Panel
The original front panel was CNC machined from 2 mm acrylic.
You can also:
- laser cut it from 2 mm acrylic, or
- cut it by hand from thinner sheet material if preferred.
The CAD model is designed around a 2 mm front panel.
Printing Tips
Archimedes Screw
For the best print quality, add a few manually placed drawn supports underneath the screw blades at different heights. In Bambu Studio I used Drawn Supports to draw at several locations along the underside of the screw.
This greatly improves print reliability while keeping support removal relatively easy.
License
You’re welcome to print these files for yourself or for friends and family.
If you’d like to sell printed versions of this design, please contact me first to request permission.
