3D contour Contact Point Boundary not working?

[Tbaker25]

Ok guys, I've been struggling with this one. Am I missing how this is supposed to work, or is this a bug?

I'm using 3d Contour to finish some specific areas of a part. I've used Touch Surfaces to accomplish this, rather than a machining boundary. However, it is rolling around and machining more than the selected areas.

Here is the path it generated. It rolls past the edge of the selected surface.

From my tests, Contact Point Boundary does not affect the generated toolpath at all. 

Tool center/inside boundary works only for the outer edges of the part. It's behaving like contact point boundary only respects machining boundary selection, not touch surfaces. This is in contradiction to the help document http://fusion360.autodesk.com/learning/learning.html?guid=GUIDA16162AB-95D5-4086-B54D-926B9A9BB429 which says

"Select a face / faces as the boundary for a 3D finishing operation.

Selecting a face (or multiple faces) as the boundary for a 3D finishing operation provides an efficient way of limiting where the tool is machining."

Any ideas what I'm doing wrong? Thanks!

Tom

[LibertyMachine]

Any chance we could entice you to export and share your .f3d file?

[Tbaker25]

Could I email it to you directly? Proprietary et al.

[LibertyMachine]

yes, but I won't be able to really do much with it until this evening. Hot job with a 2 minute cycle right now.

libertymachineshop

at

gmail

dot

com

[Steinwerks]

I can take a look at it this evening if @Anonymous is too busy. I'll PM you my email if that works.

[LibertyMachine]

Yeah, it's looking like my night is going to be too busy. Grab it if you don't mind @Steinwerks

[Tbaker25]

Thanks for the help, guys.

I appreciate you looking at my file.

I'm posting this directly to you and back to the forum for others to learn.

I spent another few hours trying to reverse engineer how this is handling it. I think it boils down to this:
Contact point boundary works fine for actual machining boundaries. Fusion doesn't see "Touch Surfaces" as a boundary for this purpose. Therefore, any attempts to constrain machining to only selected surfaces must be done via machining boundary.
I've seen no particular change in the z-axis behavior between contact point boundary on or off.

I think where I was lead astray was in the documentation where it referred to "Selected surfaces" for contact point boundary.

Tom