A linear guide on a CNC (Computer Numerical Control) machine is a component that is used to guide the movement of the machine’s axes and ensure precision. Linear guides consist of a linear bearing that is mounted on a stationary base, and a matching bearing block that is attached to the moving component of the machine. The linear bearing and bearing block are designed to have minimal play or clearance between them, which helps to keep the moving component of the machine on a precise path.

The linear guide can be of different types, such as:

• Linear Ball Bearing Guides: Consist of steel balls that are placed between the bearing and the rail. These provide smooth movement, high accuracy and good load capacity.
• Linear Roller Guides: Consist of cylindrical rollers that are placed between the bearing and the rail. These provide high load capacity and high rigidity.
• Linear Cross Roller Guides: Consist of small cylindrical rollers that are placed in a 90-degree angle between the bearing and the rail. These provide high rigidity and high accuracy.

Linear guides are critical to the precision and accuracy of CNC machines, as they help to keep the machine’s moving components on a precise path and reduce the effects of vibration, which can cause errors in the machining process. They are typically found on CNC milling machines, but can also be found on some CNC lathes and other types of machines.