Dual, Linked Five-Axis Mills Efficiently Cut Composites

The Bertsche Dual P5 mill comprises two independent, but linked, five-axis machining modules (A side and B side), each with separate machining chambers, enabling shops to machine two different parts at the same time while taking up the same overall size as the company’s single five-axis P5. Depending on production requirements, the machine can be operated A side only, B side only or both together. The concept was developed for an aerospace manufacturer to cut composites.

Twin integrated-vacuum fixture tables are designed to accept a variety of different vacuum workholding fixtures that can be quickly changed with a high degree of repeatability, according to the company. To assist part loading, each table has retractable datum surfaces that swing into place to edge-locate parts and then swing back down when machining. Thick-walled composite structures (ranging to 0.625") can be milled, scalloped, edge-trimmed and drilled on all sides. High-accuracy hole patterns and datum holes can be drilled for determinate assembly and then probed for accuracy. Parts are machined complete in a single setup.

Following what is said to be a growing trend towards cutting composites wet, flood-coolant cutting flushes debris into a full-bed-length flume system. Flood coolant is constantly circulated throughout the machine for thermal stability throughout the machine. High-volume mist collection hoods collect and vent mist. A sealing system on the linear ways protects precision surfaces from aggressive (detergent-type) coolant fluids commonly used with composites. Multiple temperature sensors on the bed and X-axis slide capture data for dynamic thermal compensation. To reduce the amount of filtration media, coolant is continuously filtered using a cyclonic filtration system. Part drying is also provided as a post-machining operation.