[MitchB]

I have spent quite a bit of time trying to figure out a good set of choices for machining a simple 2.5D part. I don't understand what a typical set of machining choices for this would be. I would like to mill a 0.050" pocket between some regions curves (seen in yellow on Region Curves attachment).

What I would like to do is:
1. Rough pass with larger tool leaving 0.005".
2. Finish pass with the same tool leaving 0.
3. Re-rough with smaller tool to get into corners and other areas where #1 and #2 couldn't reach without going over all the areas machined in #1 and #2.
4. Finish pass with smaller tool

I used 3P-Pocketing to do #1 and #2 with a 0.125" flat end mill. This looks fine and these paths are shown in the "Roughing and Finishing" attachment. (Side note: Why are 2.5D operations called "3P"?). In order to do step #3 with a 0.03125" flat end mill, I have tried many things. One operation which doesn't work is Z-level Remachining. This didn't cut into the corners left by the larger tool and there are many strange ramp-ins and outs in the middle of what should be straight lines. This is shown in the "ZLevel Remachining" attachment.

Re-Roughing instead of Z-Level Remachining also does not cut into the corners. ("Reroughing"attachment)

[svenakela]

Pocketing and contouring, that's what I use for these kind of things. Unless it's a small part then I let the 3D features do the work.
(It's called 3P because it is 3-axis Profiling)