# Eliminating negative space on final pass

**URL:** <https://forum.onefinitycnc.com/t/eliminating-negative-space-on-final-pass/18827>\
**Category:** Uncategorized\
**Created:** [February 15, 2023, 5:05pm UTC](https://forum.onefinitycnc.com/t/eliminating-negative-space-on-final-pass/18827 "2023-02-15T17:05:06Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Maplehead](https://avatars.discourse-cdn.com/v4/letter/m/b9e5f3/32.png) [@Maplehead](https://forum.onefinitycnc.com/u/Maplehead)\
**Post date:** [February 15, 2023, 5:05pm UTC](https://forum.onefinitycnc.com/t/eliminating-negative-space-on-final-pass/18827/1 "2023-02-15T17:05:07Z")

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Hi All  
I’m using MeshCAM for a 15” diameter sign. I have 1/8” raised letters, a man on a fishing boat and then 1/8” recessed water lines and a sky above pine trees. I will make my final pass using a 1/16” ball mill. How can I tell MeshCAM to not go over the negative spaces, meaning the spaces that don’t include the above parts I described? If I can do this I know I can take hours off of the finishing pass.

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**Author:** ![ChrisM](https://avatars.discourse-cdn.com/v4/letter/c/47e85d/32.png) [@ChrisM](https://forum.onefinitycnc.com/u/ChrisM)\
**Post date:** [February 16, 2023, 11:12pm UTC](https://forum.onefinitycnc.com/t/eliminating-negative-space-on-final-pass/18827/2 "2023-02-16T23:12:52Z")

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Hi Jim,

Since no one has offered you specific advice on MeshCAM yet - I will just suggest you look for a way to make a boundary around the areas you do not want to machine ( or a boundary around the areas you do want to machine - it depends which is easier ).  
I have not used Meshcam but have used 6 other cam packages to date. They all had ways to make these boundaries to restrict the cutter movements to specific areas.  
I did a google search and here is a link to the meshcam faq talking about boundaries.

[How do I control the area to be machined?](https://www.grzsoftware.com/faq/regions/)