2D Contour vs. 2D Pocket

[richardsalzman]

I am trying to select the best operation to create final passes after 3D adaptive clearing.  In the examples below, I tried both a 2D Contour and then a 2D pocket.  The resulting tool paths appear very similar.  In an online class I took, they always used the 2D Pocket to machine the bottom surface and the 2D Contour for vertical surfaces.  Is either of these better suited for this application?  Should I be using 2D contour for the best finish on vertical surfaces and 2D pocket for the bottom?

Thanks... Richard

[matty.fuller]

2D Pocket should work if you get the geometry selection right, if you're not careful it might machine away the central hub/boss.

2D Contour is good for stepping down the walls if you need to, but may require you to fiddle with stepover to avoid leaving cusps in the middle of the area.

Flat toolpath will clean it up the floor no worries and will also do the top of the hub and the top of the rim... if you don't want it to touch those use Heights to exclude them. Depending on what you've left over from roughing it may have too much engagement on the outer wall... if so I would clean up the wall with 2D Contour first, then the floor with Flat.

[richardsalzman]

Hey Matty,

Thanks for your thoughts.  This is the very first part I have ever machined after taking an online CAM course "Titans of CNC Building Block Series".  This course did not cover the "Flat" tool path.  I just experimented with it to see how it works.  Very cool!  I was able to get it to do the inside of the pocket as well as the side walls.  For some reason it would not do the top of the hub unless I created an additional Flat tool path and added the hub to the geometry. 

In either case, I am going to hold off using the Flat tool path for just a bit.  I would like to better understand the few operations I just learned.  These operations are:  3D Adaptive, 2D Pocket, 2D contour, Trace, Chamfer and a few others.  Again, thanks for your thoughts.  Very much appreciated!