Sweeps have a tremendous value to me in being able to do extrusions along a profile that change shape. I can do the same thing with a loft, but lofts don't produce planar faces where appropriate, and so it's hard to work with them. Sweeps really really do the trick, but there's a lapse I think, in my understanding of how things should work.
To me, the advantage of a sweep (in addition to getting planar faces) is the ability to specify (and parametrize) a profile, and have a changing cross-section move along that profile. The difficulty is, the way you specify a sweep with multiple cross sections is with multiple sketches, and the position of those sketches in space really matters. If am doing a sweep with a circular cross section and a square cross section, and the sweep profile is a line segment, the only sane way to think about it is to have the sketches for the 2 cross sections be at the end points of the segment. If I change the length of the segment, though, the sketches don't go with it, and so my sweep is broken, compared to my design intent, which is to have a circular cross section at one end of the segment, and a square one at the other.
Does this make sense? Has anyone else encountered this issue? What am I lacking in my understanding here?
To drive it home, here's a screenshot:
- Screen Shot 2017-04-20 at 11.45.05 PM.png (36.82 KiB) Viewed 442 times