Offset surface returns failed solids

Rhino Rhino for Windows
#1

Hi,

This is the polysurface I have now

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image.jpg1464×771 214 KB

However, when I offset these surfaces as a whole, I end up with parts that fail to offset

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This poly surface was made out of separate parts which could offset individually without any issues

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image.jpg1074×583 191 KB

The reason why I want to offset them as a polysurface is so that they will join seamlessly, instead of offsetting them separately and piecing them together, which will create awkward gaps

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image.jpg910×796 168 KB

Any idea as to how this can be fixed? Tried matchsrf/blend srf but couldn’t get them to work.

please help.3dm (14.9 MB)

#2

You should try rebuilding your polysurface such that each surface is untrimmed. For the little hole, you could use a boolean difference after the offset.

#3

How do i rebuild the surface? and what does it mean to be untrimmed? These surfaces were formed from sweeping curves.

#4

It looks a lot like a minimal surface
the normal ones are reversed so the offset fails.

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image.png560×668 11.4 KB

This is a quick reconstruction but can give you an idea of how to deal with this situation.
please help-yop.3dm (14.0 MB) please help-yop.3dm (14.0 MB)

#5

Hi Viktor,

Thanks for cleaning up the model. Did you use matchsurface to create the sides?

#6

I created some guide sections and then I used Sweep 2