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If you feel your application could benefit from higher precision, the answer could lie in removing the play (also called the “lash”) from the linear guide.

To do this, you’ll need an adjustable linear ball bushing bearing and an adjustable housing too. The good news is most Thomson linear ball bushing bearings are available in this format.

How do adjustable linear ball bushing bearings work?

Adjustable ball bushing bearings allow you to control the radial play between the shaft and the bearing surface by changing the internal diameter of the bearing. This is easy to do with an Allen (Hex) key.

Reducing the inner diameter of your linear ball bushing bearing will push the linear bearing surfaces towards the shaft. When the bearing is installed in its housing, the outside surface of the bearing plates (or bearing sleeve) sits against the housing bore. If the housing’s inside diameter is adjustable, and adjusted to a small diameter, the linear plates and balls move inward towards the shaft surface to reduce the radial play.

In doing so, the radial play can be reduced to zero clearance or a slight pre-load fit.

A note about pre-load

A slight amount of pre-load, particularly with larger sized bearings is usually ok, but avoid excessive pre-load when adjusting the radial play. Excessive pre-load will cause rough operation and may damage the linear bearing or shaft surface.

Which Thomson linear bearings are available in adjustable formats as standard?

All Thomson Super and Super Smart linear ball bushing bearings are adjustable for radial play when installed in an adjustable housing.

Closed A and MAM Bearings are not available in adjustable formats as standard but can be made to order.