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SolidCAM T-slots and undercuts

SolidCAM will do sideways slots and undercuts with a 2D profile, but there are also T-slot, undercut, and HSS operations. pdf version
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I found four ways to do a sideways slot in SolidCAM. The basic way is to use a slotting endmill cutter and a 2D profile. You can adjust that operation to use a thin endmill and program multiple cuts on multiple levels all in the single profile operation.

The next way to use the "T-slot" operation. This makes things a bit simpler since you can just point to the top and bottom of the slot to establish the multiple cuts you need. By adjusting where the geometry is, you cut to the bottom of the curve in my part, but that will make two gouges since the square tool can't create a curved shape.		 An established way to do this slot is to use HSS (high-speed surfacing). When you select this, you can make the curved surface the driving geometry. Then, use a thin cutter and a small step-over less than the thickness of the tool. This and the other operations needed some help with lead-in and lead-out so the cutter did not bomb through the corner of the part as it entered and left the cuts.

There is a 3D operation called "Undercuts" that would seem ideal for this. My problem is the user interface (UI) for this operation was so complex I could not understand how to use the operation. I finally got close to a solution, but the operations still left small gouges and did not completely remove the flange material.
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T-slot-geometry.gif
The T-slot operation was great since you could just point to the top and bottom of the slot and that set the depth of the cuts needed to make the slot the perfect width. The problem is a square-sided slot mill cannot do that radius. If the geometry you pick is the line where the radius starts, the slot will not be deep enough (to the side).

You can use the fantastic point selection method in SolidCAM to pick points on the furthest extend of that radius. This makes the slot deep enough, but will be gouging where the square tool hogs out the curved part of the slot. If you had a fully-radiused tool about the size of the slot, then the curved part would be nearly perfect, even if it takes two passes to get the slot deep enough (top to bottom).

Slot-profile-thin-tool.gif
You can use a thin tool and the profile operation to approximate the surface. Here, I have done four geometries, and used the "Multilevel" setting in a 2D profile operation to do four cuts. You can see how you could do eight cuts on eight levels to clear the slot. The great simulator in SolidCAM makes this easy.
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For a slot like this that has a curved bottom, the classic way to do this is with a surfacing operation where the curved face is the target surface. You use that same thin tool and let the software figure out how to carve the surface.
HHS-high-speed-surfacing-slot.gif
In SolidCAM you use HSS (high-speed surfacing) operation to cut this slot. It was fairly straightforward, though as usual, the dialog box layout was different for this operation than the others, especially the 2D operations. The bigger problem was that try as I might, I could not get that teal-colored excess material removed from the top and bottom of the slot. The compare function showed that was between 0.004 and 0.010" excess. I think this happens because I let the tool contact point be "automatic" and I should have explicitly tried to dictate the point to get the cutter flush to the flanges.
3D-Undercut-operation.gif
I next tried using the "Undercut" operation, you would think would be perfect for this. Unfortunately, it makes you select the whole model, and I could not learn how to put in boundaries to keep the toolpath from hitting a clamp or from leaving gouges on the side of the part. These 3D ops need a lot of training.
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