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Answers
Turns out I hadn't looked at your method/model in the right cross section:
Those sloping faces of the slot are a problem.
Back to square one I think :(
Perfection is achievable.ill post it next week unless someone beats me to it.
It appears that way, but if you were to place a cylinder perpendicular to the inside of that slot surface and rock it around the slot profile that's the resultant angle from the sweeping cylinder. It doesn't seem like it should be intuitively but you need only look at the rest of this thread to see that sweeping body geometry is anything but intuitive. I'll try to set up an assembly cross section that shows a cylinder tool following those angles on those faces when I get a minute at my desk.
Derek Van Allen | Engineering Consultant | MeddlerHere is a version using a sweep with a calculated path.
https://cad.onshape.com/documents/ec9994607320087db3682d12/w/187cdb6ffb9d97c20a33dacf/e/5b78b2655ad18c7064e36127
Alright here's a few more section views and illustrations to hopefully elucidate the unintuitive cutting path this geometry takes:
Those wonky angles you see in the cross section across the side view? Those are supposed to be there for the pin to move through the slot. That's because we're not cutting a path relative to that cross section, this whole slot is cut on a 45 relative to that origin. If you look at the side view of where our cutter would engage with the side geometry, the cutter doesn't interact with those faces at the exact midpoint of the toolpath from that view. Those faces are getting cut at those points before or after the "midpoint" of the side view of the tool sweeping through.
In this image the purple dotted line is your wonky section view where you see non-parallel cuts, and the adjustment I made in my gif above shows the true cutting dimension of the toolpath when positioned at that point in the green line as a cross section. You can see where the tool actually engages with the top face of the purple cross section drawn out in orange, and the bottom slot face drawn in pink. This is why you see those angled faces is because the cutter doesn't actually engage with those faces in the mid-plane of the part like you'd think it would. It happens both before and after the tool sweeps through the side plane.
@glen_dewsbury this example, too, falls prey to the minimum slot width constraint that the other sweep examples do because the sweep options don't allow you to specify both locked sweep direction and locked face orientation sufficient to keep the width consistent for this kind of manufacturing geometry,
Derek Van Allen | Engineering Consultant | MeddlerYou're right of course. Long, bad day, When I saw what looked like a problem, I just gave up in tired frustration.
In the cold light of the early hours of the morning a day later and yes. Looked at orthogonal to the relative direction of motion of the cam and follower, and its just fine: