How to join 2 polysurfaces into one polysurface

2 polysurfaces didn’t touch each other, how to join?
The first attachment is I want to join.
The second attachment was already join.
I want to know how to do.Join polysurface.3dm (224.4 KB)Already join.3dm (125.4 KB)
Thanks

It is possible to do that (obviously, since it was done in that second file) - the question is why you would want to do that!

It is possible that subsequent operations on this type of geometry will produce strange results in Rhino or will behave badly in downstream applications.

A fabricated steel section called double C Channel, it is fabricated by 2 C channel with some intermediate connectors.
However, some designers are lazy to draw the intermediate connectors.
I have a task to count the number of Double C channel in a building model, I need to join 2 C channel as a member first.

At that point I would assume that the length of the channels are identical at all locations or else you would have to count each length on its own. If so, you could make a block of the channel and place copies of the block. The block manager will then tell you how many instances of that block are in the file.

Hi youngken - you can do this with NonManifoldMerge.

-Pascal

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I didnt want to repost with a siimilar topic name so I hope its ok to put this here. For various reasons (1 reason being that it seems you can control extents of twist but not intensity scope), I have used loft and sweeps using identical cross section profiles etc and am then just joining. This seems to look fine, join reports 1 final polysurface, but when I look at shaded view, there are still variation where the joins originally where. What is required to have these sections homogenous?

Hello- Joining does nothing to modify the continuity of surfaces - best to back up and see

http://docs.mcneel.com/rhino/6/training-level2/en-us/Default.htm#topics/03_nurbs%20topology.htm

https://docs.mcneel.com/rhino/6/training-level2/en-us/Default.htm#topics/04_curve%20creation%20and%20continuity.htm

https://docs.mcneel.com/rhino/6/training-level2/en-us/Default.htm#topics/05_surface%20continuity.htm

-Pascal

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Thanks Pascal. Learning the differences in packages ie siltation seems to be the biggest challenge for me…surface continuity has always been implicit eg in inventor but of course nowhere near the scope of Rhino.
Excellent help!

EDIT: Most of the artcles refer to nurbs etc which I get…but Im dealing with polysurfaces here but it give me a good term reference.

In Rhino, ‘polysurfaces’ are surfaces that have been joined to at least one other surface along a common edge - there is not a lot you can do about continuity in a polysurface but you can deal with it at the surface level - i.e. Explode or ExtractSrf.

-Pascal

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Thanks again Pascal…GOLD!
Just had my morning coffee and the clouds in my head are clearing…hopefully finish this job today hehe

So there is no way to select the objects ie join and have the connecting edges kind of weld as a continuous surface? I guess then its a matter of convert to nurbs?

Use MatchSrf for this - see the Help and level2 material previously posted.

-Pascal

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