Flat: Removing extra material

[b.page12]

Hello Again, 

New user, self taught, know very little.  Creating files for the Bantam Tool Desktop CNC Machine.

I am attempting to create toolpaths to machine out an area.  This is the top of the piece.  The lower end has three outside pockets that were machined out in a previous operation from the bottom side, to .05" below depth.  All I need to do is remove a bunch of material down to the pockets.  I have tried various operations, flat, parallel, adaptive clearing, etc.  They all pretend the pocket goes all the way through and does not machine the material above them.  Eventually I created an offset surface, untrimmed it and extended it, that finally convinced Fusion to remove the material above the pockets.  However, it now removed material from the backend of the part.  i have even put them as avoid surfaced, but to no avail (see photo).

What is it I am doing incorrectly?   Thank you.

[seth.madore]

In this case, there is no need to select "Model" in the Geometry tab of the toolpath. When you did so, you told Fusion "consider this face, and this face only", so it ignores everything else, happy to cut through walls. However, we do find differences in toolpath direction, so to stay on the safe side, we would also want to tick the box for "Include Setup Model"

That said, Flat is not necessarily intended to be used as a roughing toolpath, as you are in this case. I'd suggest

[b.page12]

Seth,

Thank you for your reply.  I am more than excited to learn the proper solution you were about to present to me, but it seems your sentence was cut short.....

[seth.madore]

Aw crap, so sorry about that!

Yeah, so as I was saying....

I'd use 2D Pocket, honestly, or 2D Adaptive. Both of those would do a better job at removing the bulk of the material and then I'd come back with the Flat toolpath.

There, sentence complete 😉

[b.page12]

Seth,

Thank you again for your reply.  However, evening using 2D Pocket or 2D Adaptive, it is still seeing the pockets as a separate operation, plus it's not getting to all the material on the outside corners.  I just want it to do long strokes, left to right to remove all the material at once.  What it's trying to do now is the inner material, then come back and remove the material over the pockets.

 

[seth.madore]

The trick is to select the inner edge, and you get this:

File is attached!

P.S: Use the ALT key and select the inner edge only 😉

[b.page12]

Excellent and thank you!

I had no idea that was an option.  I really appreciate the help!