camInstructor Video Blog

Your Feedrate is Wrong - Fixing it with Mastercam

6/6/20 2:01 PM / by camInstructor Mike

Inspired by a recent Haas Tip of the Day, here I look at how to fix your 'incorrect feedrates' in Mastercam.

I created this video after watching the Haas Tip of the Day video called YOUR FEEDRATE IS WRONG. In this video Mark Terryberry discusses machining features that are close in diameter to your cutter and the effect that has on your feed rate. If you have not watched it yet I would suggest watching it before watching this video. Here is a link...

Haas Feed Rate Video

There are several options in Mastercam to try and overcome this issue. The best solution so far is the Override Feedrate option found on the Arc Filtering page. This Override only exists in Contour, Slot, and Waterline toolpaths. So as good as it is, you can't use it in every toolpath.  Here is a video from Mastercam describing its use...

Mastercam Arc Feed Rate

Some other options can be used with varying results for toolpaths that do not have this Feed Rate Override. On the Tool Settings page inside of the Machines Parameters, you can enable Adjust Feed on Arc Move. This will apply to all toolpaths in the program which may not be the desired effect. 

To adjust only specific operations, the High Feed adjustment can be applied to selected toolpaths. High Feed can adjust the feed rate either up or down depending on the amount of material engaged and also with respect to Machine Dynamics that are set within the Control Definition. Again, results may vary.

Another option is to have a post edit done where you can set a Misc Value in a toolpath to apply the feed rate compensation. Talking with your post developer would be you best bet for heading down this path.


***the movie clips are from a movie called 'The Room'. It's the best bad movie ever made. If you've never seen it, it is worth a watch!


Want to learn more about Mastercam? Check out;

camInstructor for Teachers - Independent Learners - Students



Topics: CNC, Mill, feedrate

camInstructor Mike

Written by camInstructor Mike

camInstructor Mike is Mike Wearne, an avid machinist, cnc programmer and overall connoisseur of all things machining. Mike is one of camInstructor's resident cad/cam/cnc experts and works part time at his local college teaching aspiring machinists how to program CNC Machines of all types.

Subscribe to Email Updates

New call-to-action

    Recent Posts