High Speed Machining of Unsupported Thin-Walled Structures

Cutting tool/holder configurations, which could potentially be mechanically unstable, are often used to produce thin walled aluminum structures at high spindle speeds. The combination of long cutting tool and thin walled workpiece produces a system that lacks stiffness and becomes subject to distortion. This paper attempts to qualify the distortions experienced by a thin aluminum rib machined at a high spindle speed and conventionally low spindle speed, respectively. Results show that high spindle speed, high feed rate and low depth of cut coupled with an appropriate cutting direction will maintain the stability of a thin walled structure and substantially reduce tool chatter.