What if you could run almost all of your CNC machines, not just your high-speed equipment, 10, 20, even 30 percent or more without tool life or equipment longevity decreasing, and improve the surface finish of your molds.

Feedrate optimization, a surprisingly underused CAM strategy, allows you to do just that.
Feedrate optimization is a programming tool within many CAM packages that enables the programmer to build feedrate adjustments into the CNC program in the off-line mode. It operates by analyzing the CNC toolpath and divides the motion into smaller segments. Based on the volume of material removed in each segment, the software calculates the optimum feedrate for the cutting condition. It then provides a new toolpath that is identical to the original, except with new feedrates.

Feedrates are increased to maintain consistent load, but decreased to negotiate direction changes without over- or under-shooting the geometry, given the responsiveness of the servos on the target machine. Likewise, rapid moves are applied to passes where the tool is not in contact with the workpiece to reduce the time spent “cutting air.” The results are machining routines that can significantly shorten cycle time without unduly burdening the programming effort.

Not only will you get parts off the machine faster, but the parts will be more accurate and have an improved, more consistent finish. This is thanks to accurate toolpaths carried out at the optimum rate for that particular move, condition or function. For moldmakers, the potential improvement in part quality alone may warrant applying the feedrate optimization feature in their software because these shops are accustomed to spending significant time hand-polishing molds.

Feedrate optimization can be used across the board within safe limits based on the particular machine’s operating characteristics. Individual machines can also be further accelerated within safe limits after benchmarking them by performing a simple test that requires the machine to be out of production for several hours.