Patching a hole from a removed feature

I’m attempting to remove some old features from a model so i can build newer ones and i have the offending surfaces removed… I’m trying to patch the holes created…

There are more then 4 edge curves so that seems not to work so i tried patch… The thing is it produces a lump in the middle… I’ve fiddled with the settings but i honestly have little experience with the command

Any tips on better settings? or an alterate idea to rebuild the surface?

Hello - Untrim or ReplaceEdge should help. You may want to DupBorder so that any unwanted or extra untrims around the border can be retrimmed.


Un-trim WILL work, but it sometimes needs ‘help’ when it is connected to other / joined polysurfaces. Try the following:

  • Use ‘Extract’ to separate / isolate the single surface for un-trimming
  • Don’t move it!
  • Now use ‘Un-trim’ on the edges you want to close up.
  • You can now ‘Join’ the surface back to whatever it was touching along its other edges.

I always wondered why you can’t just use untrim with polysurface… It seems more efficient if untrim already does the extract surface as needed…
If the untrim breaks the joined edge, that seems like it should just do it and give a popup message
what happenned.

untrim give me my whole original surface … Which is nice except how do i keep the trims except around the hole

It wont rejoin … tried that

Hello - that is why I suggested a DupBorder first, so you can retrim, or, use ReplaceEdge.


1 Like

hmm let me try - YOLO!



So i need to trim but keep just the piece where the hole is… there is a surface edge from another surface along the front of the hole… thoughts on how to split it off from the trim area?

Hello- can you export the surface and the neighboring ones and post that, or send to


hmm did not seem to export the surfaces although that’s a good illustration of the issue

OK so i used the border to split then used two surfaces to split the outer split

then i deleted the waste material and rejoined it all …

JOY! thanks all for your help - Learned a lot on this one!