Steel Balls for Printed Mechanisms
A few steel balls turn a simple print into a working mechanism. They roll smoothly in printed races, click into detents, add weight where a part needs it and make satisfying fidget toys. This assortment keeps six sizes on hand so you can design around what is in the drawer.
Bearings and Rotation
Drop balls into a printed race for turntables, lazy susans, spinners and slow moving pivots, with smooth steel running against plastic.
Detents and Ball Joints
Use a small ball with a printed spring or flexure to create positive click stops on dials and sliders, or capture a larger ball for posable ball joints.
Weight and Balance
SS304 stainless steel balls add dense, corrosion resistant weight to bases, chess pieces, marble runs and toys where a print needs to feel solid.
Assortment Details
Full Assortment Contents
Every item is picked from our regular stock, so you can top up anything from its own product page.
Design Tips
Printed hole and race sizes vary between printers, filaments and settings. Print a small test block with a few pocket sizes around each ball diameter and use the one that gives the fit you want.
For a press fit, make the pocket slightly smaller than the ball. For balls that need to roll freely, add clearance and keep the running surface smooth.
Frequently Asked Questions
What are the balls made from?
SS304 stainless steel with a mirror finish, for good corrosion resistance.
Can I buy more of one size?
Yes. Every size from 2 to 10 mm is available individually from our stainless steel ball listing.
Need pins for hinges and axles too?
Our Stainless Dowel Pin Assortment has 120 pins in 2, 3 and 5 mm diameters.