Hi Rob, a couple of different things going on there. One is that you have a non-planar path curve with sharp corners in it. When you do a sweep along a path with sharp corners, Sweep will try to do extensions of each section and intersect the extended portions to form a miter joint. This tends to only work very well on planar paths though, due to various things it's difficult for miters to be formed on non-planar paths other than polylines where there is a simple plane ending shape.
Basically when you have 2 non-planar curved pieces coming together, they don't hit each other in a simple plane cut, because parts of the sweep that are following the curved path away from the actual juncture point are running into each other.
Then the other thing that adds some complexity in your particular case here is that you've got the profile curve positioned on the rail but since it's at a corner point it the profile is not actually perpendicular to any rail segment, it's at a slight angle to them and so when swept since it starts out angled it will stay angled as it moves along the rail segments. You would probably want to use "auto place" mode for this instead, that's when you position the profile away from the rails (it has to be outside the bounding box around them), and then it will move the profile into place perpendicular to the rail automatically. See the 6-legged pod video tutorial on http://moi3d.com/2.0/docs/tutorials.htm for some more explanation of auto place mode.
So you'd probably want to move your profile curve off away from the path you've got there so you'd get auto place mode engaged, then when you do the sweep because you have a non-planar path it will generate the individual extended segments for you but you'll have to do some manual trimming work after that to finish things up.
I'll be out traveling today so I won't be able to get back to you on this until another day or so.
- Michael |
