3d contour undercut, not dipping into undercut.

[calebktaylor]

This is frustrating, generating the toolpaths to properly do this with the modeled radii in the corners just doesn't work.  Tool with those radii wasn't available, so I hope to profile it with a mill tool.

Fusion file using Harvey keyseat cutter with corner radii, with the broken CAM not machining the groove.

https://a360.co/32ns19w

[seth.madore · Accepted solution]

It appears to be something to do with the tool definition itself. I created a new tool using the key geometry (width, thickness, radii, root diameter) and was able to easily create a toolpath:

Duplicating the successful tool and using the Harvey defined tool, no such luck...

See attached file.

[SithechCustoms]

Two years later and this is still a problem with 3d Contour undercutting toolpath generation.  I was using a Harvey Tool supplied tool model of a full radius keyseat cutter P/N: 968562 and Fusion would not allow it to do any undercutting.  I removed the "shaft" in the tool geometry and now it undercuts just fine.  I should clarify that the shaft in no way interfered with the part model to reach the geometry I needed.  I was having the same problem with a lollipop cutter but it's a relieved shank without any modeled "shaft" in the tool library, is there a fix for this issue as well?

[Anonymous]

I second SithechCustoms post. I just wasted an hour trying to figure out why a lollipop cutter would work and a full radius key way cutter wouldn't. Then I found this post and deleted the Harvey Tool supplied shaft dimensions and it worked no problem. For what it's worth I'm using Harvey Tool 43493-C3 full rad keyway cutter and a 994732-C3 lollipop cutter.

[sean]

This is still a problem in 2023.  If there are shaft dimensions present (even ones that I typed in myself), the toolpath will not dip into the undercut.  If I delete the shaft dimensions, it does dip into the undercut.  This workaround works okay in some situations, but now I will have no way to visualize shank clearance for any of my toolpaths.