camInstructor Video Blog

Controlling OptiRough | Xometry Mill Test Part - Video 5

8/25/21 7:00 AM / by camInstructor Mike

Often when using OptiRest, tool motion happens where you don't want. Let's look at controlling this toolpath.

Link to download the CNC Mill Test Part Package...
Another video talking about OptiRough / OptiRest. We have some new things to discuss in this one though. Specifically, controlling where tool motion takes place during the OptiRest toolpath.
The most common instance of this extra motion comes from small cusps left behind by previous toolpaths. When roughing 3D parts, there will be varying amounts of material left on different locations of the part even when the tool is leaving the commanded amount of material. This extra material can cause furture toolpaths to add extra cuts to remove these bits. Sometimes, this is the goal. But when its not, this is just wasted cycle time.
In the Stock setting, there is a function called Adjustments to Remaining Stock. This does just that, adjust the stock. You can Use as Computed, Ignore Small Cusps, or Mill Small Cusps. Those little bits of extra material, ya, we refer to those as cusps. 
Ignore small cusps basically allows use to not cut these areas where slightly more material is left than our Stock to Leave setting. If you stock to leave is 0.01 but the toolpath sees 0.011 of material in some places, it will add tool motion there. Obviously, you may not want to waste the time to cut 0.001 of stock.
The only limitation with this setting is you cannot ignore more than the radius of the tool you are cutting with. So, 1/32 bullnose, max setting is 0.031.
This Stock adjustment works great for small cusps but what about entire regions? If you are trying to avoid a hole or pocket, the Skip Pockets setting is a great first option to explore. If this is not working to your satisfaction, you may have to create some geometry. You can easily draw a containment boundary and chain that instead of using the Silhouette Boundary we have been using. 
Lastly, since we are using a stock model. you can always make adjustments to it. There is a setting called Additional Offset but this only works in the positive direction, as in you can only add more stock to the model not less. Another option is to apply a dummy toolpath to one stock model and then create a new stock model from that...then feeding this new stock model to your real toolpath. Getting deep in the weeds now but just pointing out the endless options you have here to get control of the toolpath you want.


Want to learn more about Mastercam? Check out;

camInstructor for Teachers - Independent Learners - Students


Topics: Mastercam, 2022, Xometry

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