Ball bearing

A print-in-place bearing from a standard trade size.

A deep-groove ball bearing that prints already assembled: two races with a raceway turned into each, and the rolling elements captured in the channel between them. There is nothing to press together — it comes off the plate turning.

Pick it by trade size and the bore, outside diameter and width come from the published table (ISO 15 for the metric series, the inch R-series, and the flanged F/MF sizes) — over a hundred of them, from a 2 mm MF52ZZ to a 60 mm 6312. Custom hands those three dimensions back to you.

Everything else is derived from them, because a deep-groove bearing splits its radial section into thirds: each race is one third thick, and the channel between them is the last third. The element is deliberately *wider* than that channel, so it cannot escape sideways — that is what “deep groove” means, and it is why the bearing holds together with no cage.

Three rolling elements, and the choice matters more than it looks. Balls run with the least friction but want a rounder raceway than FDM usually lays down. Rollers bear along a line and print easily. Dumbbells are waisted so they ride on two narrow bands — they self-centre and resist jamming, which is why they are the default.

Read the two rows before printing. *Elements* is solved rather than chosen: it is how many fit around the raceway without touching, so loosening the spacing can quietly cost you half of them. The second row appears only when something is too small to print, and it names whichever measurement binds hardest — the material behind the raceway, the lip at each race face, the rolling element itself, the running clearance, or the space between neighbouring elements. The miniature end of the catalogue trips it: an R2 leaves 0.49 mm behind the raceway where a printer wants about 0.8.

Pairs with the pulley and gear train families for full drivetrains; stays editable in the property panel.

1. Open the Generate panel from the left sidebar and choose Ball bearing (under Gears & drives).
2. The bearing drops in pre-assembled as separate bodies. The parameters open in the Properties panel, where you set them.
3. Pick a trade size — 608, 6000, R8 and a hundred more — or Custom to enter bore, outside diameter and width yourself.
4. Choose the rolling element, then read the Elements and Race web rows before you print.