Fusion 360 Lathe - Paths generate below Inner Radius

[rw_skinner]

I have some stock I need to face and turn the OD down on one machine before transferring to another machine.  I keep setting inner radius to selection, but I've also tried a diameter of 1.375.  When I create the tool path, it continues to follow the part profile like a standard roughing pass.  What I want on the roughing pass is a nice straight cut at the diameter I specify regardless what the part profile is, then a finish pass on the parts major OD.  How can I make this happen without creating another model?

The Blue selected OD below is the minimum OD I want to cut.  So roughing would be that OD + stock to leave.  Finish would be that OD of 1.375.

It's hard to see, but just to the right of the blue, the model is only .005" smaller.  It's generating that tool path also which I don't want.

[akash.kamoolkar]

@rw_skinner just guessing here for now until i can look at the actual file (if you can attach it), but try checking the parameter "extend to stock" in the passes tab.

Regards,

[rw_skinner]

Extend to stock fixed the roughing pass, but the finish path doesn't start at the front of the material at Z 0.0

No Extend to stock on the finish options.  I'm not able to share the model unless I do one totally different as an example.

[rw_skinner]

Here is a sample model.  BTW, the only way I could force this to work was to add another roughing toolpath, with the right tool, feeds and speeds, and No Stock to leave.  Is that the only way?

[akash.kamoolkar]

@rw_skinner the toolpath extension in front is controlled by the parameter Z clearance in the links tab. you can't set it to 0 since it represents a safe distance for the tool to approach the stock but you can set it to a very small amount to essentially not get that extension.

Regards,

[rw_skinner]

I'm sorry, I have no clue to what you're saying. My finish path doesn't have a tool path extension? Did you look at the model? The finish tool doesn't start at the front of the material, it start where the profile is, even tough it's supposed to cut all the material to the inner radius or 1.375. So why would it leave the end bigger than the rest?

[akash.kamoolkar · Accepted solution]

@rw_skinner okay i think i understand. you want the finish pass to follow the inner radius instead of stopping at the model. Right now there's no way to do this (other than the workaround you mentioned). We are, however working on being able to exactly that (add an axial extension to the finish pass so it follows the exact same path as the roughing operation along the inner radius.

Regards,

[akash.kamoolkar]

@rw_skinner another workaround would be to add a tangential extension to the front of the finishing toolpath that extends to the stock front.

Regards,

[rw_skinner · Accepted solution]

Maybe I'm overlooking it, but I never found an option for a tangential extension for finishing passes.  Only on the roughing pass.  Never mind...  I had rest machining turned on when I was trying different things...