Trim / Untrim workflow

Rhino Rhino for Windows
1

Hello!

So i’m having trouble with the trimming and untrimming workflow. Mostly the untrim because it explodes the surface all the way back to its untrimmed form. At the moment the model only has 3-4 trim operations on these surfs but once I start to add detail it would be a lot more than that. I have tried several of the untrim commands and they all have the same result.

Is this because I use both split and trim (from curves) to trim the surface? I can’t understand why it does that and it’s very time consuming to trim it back to where I need to.

Also from a workflow perspective I use curve on surface with history from surface intersects or projected curves in another application for timming. Is a web of the intersect command my only option here, seems to be one of very few with history. Even then the trim edge wont update when I edit the curve either, is that a possibility?

Any help appreciated.

cheers,
Shaun

2

Hi Shaun - Untrim removes trim curves, it does not undo Trim operations, so to speak - that is, it does not know how the trim got there, it just throws it away. Note the Untrim* commands have a command line option to keep the trim objects - if it untrims more than you want, this set of curves is handy for getting back to how it was.

RemoveEdge may be helpful sometimes, to avoid a complete untrim.

-Pascal

3

Thanks for the reply Pascal, So how do you edit trims? Is it always an explode job? I’m sure I saw a video somewhere where you could edit the object used to trim a surface and it had enough history to update the operation. But alas I cant find it!

Thanks,
Shaun

4

Hi Shaun - ExtractSrf, then mess with the trims is what I would do. Trim does not know about History.

-Pascal