The DistBetweenRails setting at least produces somewhat clean intersections:
However, I must confess that I discovered that other CAD packages also do have a bit of trouble with this (weirdly, increasing the size turned out to be the solution), but it really should be a 1-click operation.
Doing the manual work, I did discover that splitting edges projects very well which was nice:
In the end, I just did a revolve to get the job done (with lots of manual trimming, though):
But anyway, in case someone at McNeel wants to improve the chamfer command in the future so it’s really just 1-click, here’s an example you can throw on the pile:
PS. While doing the above, I noticed quite a slowdown in Rhino… the entire thing is just an 80mb file with little history and I’m working in isolation mode anyway, so unsure where that is coming from…
Right, that’s why the other CAD package I tried was able to do the chamfer in one go once the size was enough to consume that small segment. Rhino should be able to do the same.