Re-Join surfaces and remove Tangent edge

Draw a Rectangle and make a fillet on 1 edge.
→ Extrude the Rectangle by X → Cap command = closed Poly with 15 Edges & 7 surfaces
→ Duplicate Reactangle → move duplicate by X → Loft between and Cap command = Closed Poly with 9 Edges and 5 surfaces

Question: Is it possible to remove the tangent edges end rejoin the 3 surfaces that includes the fillet back to one after extruding.

Lofted (right):

Extruded (Wrong):

  1. Explode
  2. untrim
  3. join

Hi David -

Yes, you can use the MergeSrf on those.

Question: what makes that wrong? Downstream processes might have issues with surfaces that are not split at their tangents.

Does not understand what untrim do in this case

mergesrf does not seem to work for me. Creates wiered surfaces

Edit: mergesurf with radi = 0 works. thank you

I need 4/5 or 6 sided Polysurfaces for later tasks with an thrid party plugin. I have to split my geometry by hand into pieces that are suiteable for post processing.

Hi David - if you set UseExtrusions to make polysurfaces and ExtrudeCrv to SplitAtTangents=No, you should get what you need here from extrusing.


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Thank you Pascal.

That helped kind of… I tried to rebuild the surfaces but rhino kept splitting the surfaces and after i mergesrf them the srf stopped overlapping and booleansplit didnt work. Spent 8 Hours yesterday on the model and didnt get it to work.
Today in started from zero and it worked without an Issue.

I drawn the conclusion that remodelling already cut objects is a pain and i startet to save my work steps in layers… Hope this will work in future as well :).