I am projecting them onto the same curved surface and they are drawn from on the same plane so I am not sure why they are off slightly but this is affecting the next sweep2 I am trying to do.
Overall steps I am following laid out. what I am trying to achieve is on the right, the red sphere is where the problem is occurring and I think it has to do with these guide curves being a little out of alignment from the projection step prior.
Please advise, so people looking into it can be precise.
In the meantime, regarding your rhino grid (CPlane) reset, one of the easiest ways is to have your 4 views open, click inside the perspective, run the CloseViewport command (it will kill the perspective view), then run the 4View command, hit enter twice to restore your perspective.
Note: this isn’t the same as using “AutoAlignCPlane”—I checked and you didn’t have that enabled so the 4View method took care of it.
That helps, and maybe not so much given all the conditions (your curve ‘misalignment’ might continue to make the sweeping complicated in plain 3D)—'makes me think you could follow some 2D-to-3D workflow using OffsetCrvOnSrf and FlowAlongSrf to make sure your ‘sweeps’ are cleanly unified, leaving your junction ‘open’ to sweep the last path:
NOTE:
The above example is a quick one in which I ignored your sweep profiles (made my own rectangles), but I did use your projected curves when offsetting on the surface. It’s just for demonstration purposes as you know more about your project needs. It still applies to modeling the ‘Y’ clean.
I’m sure other more talented modelers can provide further insights!
See below, what you have is expected, unless you change the curve(s) or “cheat”. Are you, in a later step, intending to fillet the box profile surfaces? That would change the way of “cheating” (manually modeling the intersection).
Interesting, thanks for the explanation. I figured there had to be a reason but couldn’t visualize it. I would like to have a “clean” union so I can offset and use this geometry to build on top of down the line.
Any suggestions for how to achieve this are welcomed. This is a free form project so there is room to adjust, but I would like to get something close to what I am attempting here.
Idea 2: Make a base surface that has the curvature you want and use offset curve on surface to create the Y shape, which you then cut out of that base surface. Then either offset up (or down) by the height (or you can offset the Y shape first up and then down by an appropriate amount and connect the two Y shapes with a loft). offset surface.3dm (476.3 KB)
Idea 3: Project the curve that has the overall shape onto the cplane (don’t delete original), extend both ends by a bit. Then offset the projected curve up and down the appropriate distances. Make your profile curves much taller than they need to be. Do your sweeps with the tall profiles and then use the offset curves you made earlier to trim to level. taller profiles trimmed with offset curves.3dm (471.3 KB)
I’m not sure how well any of my ideas would integrate with the rest of your project.
Only if the two curves, projected onto a single curvature surface, were identical and oriented symmetrically across the surface’s curvature, the box sections would match up. So, there are only two options - change the curve(s) or manually “cheat”.
