Ball Screw Fidget

This item is fully printable and does not require any additional parts!

A satisfying mechanical fidget toy inspired by the smooth motion of a ball screw mechanism. Twist, slide, and roll the internal balls through the helical track for a simple but addictive desk toy experience.

This model is designed to be compact, tactile, and fun to use, with visible red balls moving through the slotted carrier as the mechanism turns. It makes a great print for anyone who enjoys mechanical toys, fidget gadgets, or display-worthy 3D printed mechanisms.

Features

• Smooth screw-style fidget action
• Uses small printed balls as the moving elements
• Compact desk-friendly size
• Great visual contrast with white body and colored balls
• Fun mechanical feel without electronics or hardware
• Simple, clean design that looks great on a desk or shelf

Printing Notes
Print the main body and balls separately for best results. A contrasting color for the balls is recommended so the motion is easier to see through the slot. Make sure the balls are cleanly printed with a 0.12 mm layer height, remove strings. I have had the most success by printing the balls object by object, since they have quite a high failure rate. This requires 3 separate prints for all the balls. I wanted to keep them brim free to minimize post processing.

The rest of the parts were printed on one plate with 0.2 mm layerheight.

The screw, aswell as the housing have a notch, running parallel to the rolling surfaces. This was implemented to put the Seam line inside the notch.

I used Bambulab PETG HF for this print.

Recommended Colors
White, black, or gray for the main body, with bright red, orange, blue, or neon balls for contrast. But Any color works