I am trying to make an aesthetically pleasing outer casing for a client, and it's giving me a migraine. I have guide curves for the side profile, and cross-sections (made from splines) for the levels to loft over, but the surface is losing its tangency for unknown reasons. I am doing half at a time, intending to mirror the surface later. Since I couldn't control the orientation of the endpoints of my splines, I added a straight line segment from the centerline for 3mm before starting my spline, adding a tangent relation between the line segment and spline. When I loft, however, the lofted surface does not follow all of my profiles! On some (but not all!) of my profiles, whereas my line segment is normal to my mirror plane, the lofted surface is tangent, resulting in an unsightly ridge that is anything but aesthetic. It later follows the spline part of the profile just fine. I use the pierce constraint to make sure my profiles intersect my guide curves.
Also, I have some extreme (for SW apparently) curvature that a single loft can't handle, so I end up with 3 lofts, a sweep, and a fill surface. These don't play well with each other or blend, resulting in discontinuities in curvature after knitting, despite being derived from the same sketches. And SW doesn't let me apply any kind of tangency constraints between the surfaces.
On one of the lofts in particular, two of the three profiles are straight lines, and the third is a spline. The resulting lofted surface is nowhere near following the straight line, even after i broke it up into as many line segments as i had in my spline. What is wrong with SW (or what I'm doing with SW)? Why doesn't it follow the profiles given it?
ProE can do what I want effortlessly with the boundary blend feature, but my client uses SW, and needs to be able to adjust the case at a later date, so I can't just import the ProE surface. Also, surfaces made in SW seem to "wiggle" or undulate more than those made in ProE from the same curves. No matter how carefully I make my splines, it finds a way to buckle and not follow my profiles....
Please help me if you can! Email me if you'd like me to send you the part in question.