HelixCore – Press-to-Spin Squishy Ball

We might look similar, but they don't spin like me. 😏

I saw many amazing squishy ball fidgets recently and couldn't stop thinking:

What if a squishy ball could spin by itself?

Inspired by classic spinning tops, HelixCore transforms a simple squeeze into a spinning motion.

Just:

👉 Press

👉 Spin

👉 Release

No twisting.

No second step.

No extra hand required.

Just pure mechanical satisfaction.

⚙️ Hidden Engineering

Inside HelixCore is a mechanism that converts squeezing motion directly into rotational motion.

The design combines:

• Ball Screw Mechanism
• Clutch System
• Elastic Return Drive
• Dual 608 Bearings

From the outside, it looks like a simple squishy ball.

Inside, it's a surprisingly complex mechanical toy disguised as one.

👨👩👧👦 Comfortable To Play

HelixCore was designed with comfort in mind.

All exposed corners and edges have been rounded wherever possible to create a smoother handling experience and avoid unnecessary sharp contact points during play.

🔧 Hardware Required

HelixCore requires only:

• 2 × 608ZZ Bearings
• 1 × Rubber Band

608ZZ Bearing Size:

• 22 mm Outer Diameter
• 8 mm Inner Diameter
• 7 mm Thickness

No magnets required.

No glue required.

🪢 Rubber Band Selection

HelixCore is intentionally forgiving when it comes to rubber bands.

I've successfully tested bands ranging from 28 mm to 40 mm.

Different rubber bands simply change the feel of the fidget:

• Softer bands = lighter squeeze
• Stronger bands = faster rebound
• Tighter bands = bonus finger workout 💪😆

Feel free to experiment and find your favorite setup.

⚖️ Optional Flywheel Weight System

Each hinge includes a built-in weight pocket on the back side.

By default, the cavity is sized for M5 nuts.

Adding weights increases rotational inertia and can extend spin duration.

Prefer a different size?

The weight pockets are generated using negative parts in Bambu Studio, making them easy to customize for other nut sizes if desired.

Weight installation is completely optional.

HelixCore works perfectly fine with or without additional weights.

🎨 Print Profiles

Standard Edition (Fast Assembly)

Recommended for most users.

Shell assemblies are grouped together to reduce part count and assembly time while maintaining the same spinning performance.

A great choice if you just want to print, assemble, and start playing.

Color Custom Edition – Classic

The original multi-color shell layout featured in the cover images.

Designed for builders who enjoy custom color combinations while keeping the original visual proportions.

Color Custom Edition – Enhanced

An alternative shell layout featuring larger accent panels and stronger visual contrast.

Perfect for bold color schemes and builders who want the colors to stand out even more.

💡 Design Philosophy

Looks like a squishy ball.

Plays like a spinning top.

Powered by engineering.

This is exactly the kind of design I love creating:

Funny Design, Serious Engineering.