Precision Guidance and Alignment: The main purpose is to guide one component (like a guide pin, drill, or punch) along a predetermined path with very small clearance, ensuring precise alignment and repeatable, high-precision performance.
Reduced Friction and Wear: Guide bushes are often made from materials that minimize friction, such as hardened steel, bronze, or self-lubricating composites, which extends the lifespan of both the bush and the components it guides, thus lowering maintenance costs.
Support: In applications like CNC Swiss lathes, guide bushes provide rigid support to the workpiece (bar stock) close to the cutting tool, preventing it from bending, vibrating, or "throwing off" during machining of slender parts, which improves accuracy and safety.
Versatility: In woodworking with a router, a guide bush attaches to the router's baseplate and follows a template, allowing for consistent and precise cuts for applications like inlays, dovetails, and mortising