Inspecting T6 Hexalobe Driver

[[Ev...]]

I've got a T6 hexalobe (medical) with a profile tolerance of .03mm (no DRF). Profile is toleranced basic as seen below -
Base alignment looped with break condition of <0.005. BA uses a plane on the top of the hexalobe feature as the spatial, a 3D line using arcs from the internal radius on opposite sides for clocking, and the origin is the XY location of the ID cannulation, Z origin is the top plane.

I'm having a tough time scanning the hexalobe feature reliably, using a .3mm stylus. I tried using a freeform with a section taken at 2 different heights along the hexalobe, but it seems like the stylus is getting caught up when transitioning from the internal radius to the external radius. The hexalobe is 1.3mm in length. I'm thinking about going the single points route instead of scanning next week when I'm back in office.

Wondering if anyone has any advice on what methods I should use for this feature?

Thanks in advance

[[Ma...]]

I would take points too hoping for no collision when retracking - if you have an active head, then curve with really slow speed and low measuring force.

[[Ke...]]

Are you sure that the Base Alignment is stable? (Looping the alignment and verifying the Deta values?

[[Ev...]]

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We have a passive head (XXT), so beginning to think that points are probably the only way to go.

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I didn't look at the delta values, but given that it broke the loop after 2-3 iterations, I'm assuming its stable.

[[Cl...]]

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I do a lot of these drivers. I use the opposing OD radii, constructing a 3d line rather than the ID radii.
This longer clocking line may help. Also, I use the larger OD (cylinder) for my Base Alignment Spatial.
Use the plane as the Z origin. Probing dynamic at 30% and scan very slow.

[[Ev...]]

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So you're normally setting up your BA like this?
Or are you using the thinner OD closer to the hexalobe for the spatial?

[[Cl...]]

Correct, base alignment like you show. The smaller OD should be fine. Make sure the cylinder depth is at least 3x the diameter.