Crossed-roller bearings, from Bayside Motion Group, Port Washington, N.Y., provide high accuracy and low friction, and are an inexpensive alternative to air bearings. Crossed rollers contact the bearing way only on its diameter. This generates pure rolling action, reduces friction, and lengthens bearing life.

The bearings have a hardened and ground solid way, which provides stiffness and rigidity and lets them carry loads up to 5,800 kg. The crossed configuration of the rollers in the bearing is said to allow easy mounting in any orientation — horizontal, vertical, or horizontal with vertical cross-section mounting.

The bearings are available in sizes from l to 9 mm with travel lengths from 20 to 900 mm. The company can manufacture customized components for special applications including vacuum and clean-room environments for the semiconductor industry.