Toolpath Filter Achieves a Perfect Surface Finish

Mar 13, 2015 | Blog

There are many factors when trying to achieve the perfect finish on a machined 3D part . I’d like to focus in on the toolpath filtering options available for CNC machines and CAM software.

Toolpath Filter in CAM Software

In many CAM systems you are able to set a tolerance for how accurately you would like to follow the surface with the tool. If you have a large tolerance set in your CAM you will lose detail or tolerance in your part. On the other hand, if you set the tolerance too low you will have more code, processing time increases along with the risk of vector points being visible on your surface. Filtering and smoothing options exist in the CAM software and work by shifting and removing points.

A toolpath filter in the CAM is based on shifting and removing points.

Toolpath Filter in CNC Milling Machine Control Software

But what about the option of using a smoothing feature on the milling machine itself? In the case of DATRON’s HSC Pro software, there is a proprietary smoothing toolpath filter that works on a totally different basis. Instead of removing points and losing tolerance on your part as with the smoothing in CAM, this toolpath filter adds points within the tolerance set in the CAM. The machine also calculates to five decimal places (metric) giving a more accurate surface. By adding points and increasing the read ahead of the machine, you don’t have to worry about losing detail while creating a smooth finish. The DATRON smoothing toolpath filter also monitors the jerk. Monitoring the jerk of the motors ensures a smooth machine motion while eliminating excess stress on the machine at high feed rates.

The results (above right) of using the PefectCut toolpath filter within the DATRON HSC Pro control software.
The PerfectCut toolpath filter or smoothing function within the milling machine control software has a significant effect of surface finish.

So in conclusion, running a smoothing toolpath filter in the machine you are able to have faster calculation time from your CAM along with a more accurate part requiring less optimization in the CAM software.