# Patch fail split/trim

**URL:** <https://discourse.mcneel.com/t/patch-fail-split-trim/40092>\
**Category:** Rhino for Windows\
**Tags:** rhino, rhino5\
**Created:** [January 4, 2017, 7:22pm UTC](https://discourse.mcneel.com/t/patch-fail-split-trim/40092 "2017-01-04T19:22:27Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Mauricio\_Alvarez](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/mauricio_alvarez/32/50856_2.png) [@Mauricio\_Alvarez](https://discourse.mcneel.com/u/Mauricio_Alvarez)\
**Post date:** [January 4, 2017, 7:22pm UTC](https://discourse.mcneel.com/t/patch-fail-split-trim/40092/1 "2017-01-04T19:22:27Z")

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Hi everyone, i’m trying to trim or split a surface made with Patch, but im moment i do it, the surface turns weird just like the picture. Someone can told me how to fix it.

Before

 ![](https://global.discourse-cdn.com/mcneel/uploads/default/original/3X/7/f/7fe02ab3a3ba3c40ba3c578f0105ba2b104e6d55.PNG)

After

![](https://global.discourse-cdn.com/mcneel/uploads/default/original/3X/d/c/dc361f5ff34d2646808ba836c9e69fc83b68c092.PNG)

Mau

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**Author:** ![pascal](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/pascal/32/479395_2.png) [@pascal](https://discourse.mcneel.com/u/pascal)\
**Post date:** [January 4, 2017, 7:34pm UTC](https://discourse.mcneel.com/t/patch-fail-split-trim/40092/2 "2017-01-04T19:34:19Z")

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Hi Mauricio - my guess is the trimming curve there is a little messy - possibly it has a small loop in it, something like that - can you post the curve and surface?

-Pascal

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**Author:** ![Mauricio\_Alvarez](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/mauricio_alvarez/32/50856_2.png) [@Mauricio\_Alvarez](https://discourse.mcneel.com/u/Mauricio_Alvarez)\
**Post date:** [January 30, 2017, 7:32pm UTC](https://discourse.mcneel.com/t/patch-fail-split-trim/40092/3 "2017-01-30T19:32:40Z")

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Hi Pascal

Thank i had check the line out, actually the line got 2 intersection points it was that.

Thanks a lot

Mau