Sweep on two rails is making an uexpected shape.

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cadenjb
Posts: 1
Joined: Sat Jan 22, 2022 3:11 am

Sweep on two rails is making an uexpected shape.

Post by cadenjb »

OS: Windows 10 Version 2009
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Locale: English/United States (en_US)

I'm trying to make a visor for a helmet and to do so requires me to bend a curve around another two curves until it meets another curve (yes lots of curves). But sweeping on two rails does not do the trick as the end result is not usable.
Had the other two curve profiles go along the ruled surface in a sweep on two rails and that was my result?
Had the other two curve profiles go along the ruled surface in a sweep on two rails and that was my result?
Screenshot 2022-01-22 000759.png (237.19 KiB) Viewed 2467 times
I'm aware that it may be because the rails are connected at an angle.
Ruled surface between two rails for sweep on two rails
Ruled surface between two rails for sweep on two rails
Screenshot 2022-01-22 000512.png (213.8 KiB) Viewed 2467 times
There are a few other methods to make the same shape that I'm trying to achieve but I can't get any of them to work. To be precise I'm trying to make a 3D curve connecting 4 curved sketches. So after sweep on two rails failed I tried a Gordon surface, but this will crash my program any time I try, when creating the Gordon surface I selected the two "ribs" and the two "spines". After that failed I tried discretizing each wire and then forming a surface from their point clouds. This did make a surface between all 4 lines but none of the 24 combinations of connections made a shape that was usable. I tried making a surface from 2, 3, 4 boundary edges (4) which also crashed my program. I tried adding another line to create a section inside of where I wanted my 3D curve and doing a sectional surface. That almost worked but for an unknown reason one of the curves twisted a 180.
Sectional surfacing doing a twist
Sectional surfacing doing a twist
Screenshot 2022-01-22 002032.png (178.93 KiB) Viewed 2467 times
The only solution that even was able to cover the gap where the visor is without crashing or doing something unintended was creating a surface between two edges. However this didn't follow the rails I set up and there was no way to do so. Anyways, what I'm asking here is is there a way, to make a curved surface between four curves?
Attachments
RPHelm-v0.1-atmpt5.FCStd
The helmet
(978.02 KiB) Downloaded 19 times
Here I've created a surface between two edges, which looks fine but isn't able to confine to the other two rails I need it to follow (I really only need it to follow the profile of the visor rail the other one is optional)
Here I've created a surface between two edges, which looks fine but isn't able to confine to the other two rails I need it to follow (I really only need it to follow the profile of the visor rail the other one is optional)
Screenshot 2022-01-22 001105.png (229.89 KiB) Viewed 2467 times
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