Sweep 2 doesn't work?

I’m not sure why these lines won’t finish the sweep 2 command? I was working off another persons model and dup bordered the back of their model. I was going to sweep 2 and join them to close it off. I can loft so it’s not a big deal, but is there something wrong with these lines or is this a bug?Cant_Sweep_2.3dm (51.0 KB)

If you explode your rail curves and then run SelShortCrv, you will find 4 curves on the outer rail that are smaller than file tolerance, as well as one on the inner rail that is very close to it (.002 units long). Eliminate the tiny ones, fix the one gap in the inner rail left by deleting the .002 curve and join all up. Then Sweep works - however, not the best quality stuff by a longshot. Turn on curve graph to see, there are some really bad spots. Unless they have to match something else existing, I would look at remaking them…

–Mitch

Ah I see, Thanks. I’m working off someone’s model just to do a bid. It will get re-drawn from scratch if we get the job. Appreciate the help.

Why sweep 2 fails along the red rails?
(If I wanted to also include the green rails, the sweep command 2 is a limit, because the tracks would become 3 here, is a Rhino limit).
To do what I should build everything manually, surface to surface … too much time …
Sweep 2 incorrect.3dm (26.6 KB)

Hmmm. There is no way for Rhino to have any idea what you intend the lower part to look like, it only sees the input curves, nothing else. I’m not really sure what else you could possibly expect to happen here. It takes a few seconds to build from lofts.

-Pascal

Thanks Pascal. Strangely, if I choose a single rail and use the command sweep1 works, with two binary nothing to do.
Not to make more comparisons, but with UGS NX and Shark fx is successful.

I know that you can follow other paths, but this exercise is simple, imagine a form with many rails… build surface for surface is a little laborious, in my opinion.