# Trouble creating union then Subtract

**URL:** <https://discourse.shapr3d.com/t/trouble-creating-union-then-subtract/22919>\
**Category:** Modeling Questions\
**Created:** [December 8, 2022, 5:16pm UTC](https://discourse.shapr3d.com/t/trouble-creating-union-then-subtract/22919 "2022-12-08T17:16:11Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![SkillipEvolver](https://avatars.discourse-cdn.com/v4/letter/s/b4bc9f/32.png) [@SkillipEvolver](https://discourse.shapr3d.com/u/SkillipEvolver)\
**Post date:** [December 8, 2022, 5:16pm UTC](https://discourse.shapr3d.com/t/trouble-creating-union-then-subtract/22919/1 "2022-12-08T17:16:11Z")

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Hi guys,

Pulling my hair out.

Trying to create a subtract (1 body from another).

Probably something simple I’m missing.

I’ve created a diamond mesh (geometry) with 5cm depth. Which I’m trying to SUBTRACT from another body (a block of wood/rectangle), to create the design.

But having trouble first of all UNIONising the bodies.

Can someone help?  
It’s probably something simple but I just can’t find the tool…

Quick YouTube (better) description here…

[![](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/c/9/c954a3110294547a3b4c17ec8dd89243d58fe3e6.jpeg "How to Union mult-lie bodies? (100+)") ](https://www.youtube.com/watch?v=5Wca6RaWqu4)

Many thanks!!

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**Author:** ![Stephen](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/stephen/32/16350_2.png) [@Stephen](https://discourse.shapr3d.com/u/Stephen)\
**Post date:** [December 8, 2022, 6:07pm UTC](https://discourse.shapr3d.com/t/trouble-creating-union-then-subtract/22919/2 "2022-12-08T18:07:47Z")

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If you still have the Sketch with the holes, you can simply extrude the holes inward.

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**Author:** ![Stephen](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/stephen/32/16350_2.png) [@Stephen](https://discourse.shapr3d.com/u/Stephen)\
**Post date:** [December 8, 2022, 6:36pm UTC](https://discourse.shapr3d.com/t/trouble-creating-union-then-subtract/22919/3 "2022-12-08T18:36:47Z")

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Or if you want to do it your original way, you could group the objects you wish to subtract into a folder, then subtract the whole folder from the main object.

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**Author:** ![TigerMike](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/tigermike/32/32650_2.png) [@TigerMike](https://discourse.shapr3d.com/u/TigerMike)\
**Post date:** [December 8, 2022, 6:45pm UTC](https://discourse.shapr3d.com/t/trouble-creating-union-then-subtract/22919/4 "2022-12-08T18:45:45Z")

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Have all the pieces you wish to subtract in a folder. When you do the subtract you can select the folder to subtract from.

[https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/2/d/2de0febfa7d5d59492e59a97e50340e3990b719a.mov](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/2/d/2de0febfa7d5d59492e59a97e50340e3990b719a.mov)

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**Author:** ![Istvan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/istvan/32/23668_2.png) [@Istvan](https://discourse.shapr3d.com/u/Istvan)\
**Post date:** [December 8, 2022, 9:48pm UTC](https://discourse.shapr3d.com/t/trouble-creating-union-then-subtract/22919/5 "2022-12-08T21:48:10Z")

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The bodies don’t intersect. What do you expect from the Union tool in this case?

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**Author:** ![SkillipEvolver](https://avatars.discourse-cdn.com/v4/letter/s/b4bc9f/32.png) [@SkillipEvolver](https://discourse.shapr3d.com/u/SkillipEvolver)\
**Post date:** [December 8, 2022, 10:24pm UTC](https://discourse.shapr3d.com/t/trouble-creating-union-then-subtract/22919/6 "2022-12-08T22:24:24Z")

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Hey all,  
Thanks for the help with the subtract tool. It’s worked well.

The more I got involved doing this, the more I considered that, in reality, if this asset was to the up on a videogame for example… All this extra geometry would be excess.

More efficient to use a texture image… but hey ho. At least it gave me experience with the subtract tool. Appreciate it.

In continuing my work I has another issue arise after using the intersect tool.

Long n short, it’s basically left an imprint mark on another body I have in my scene. And I’m wondering how I can clear that outline/imprint away? / Erase it?

[![](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/b/8/b8aa7f53417028bfb0b8a24039e684d352af4df6.jpeg "Trying to remove left over ‘line trace’ from intersect") ](https://www.youtube.com/watch?v=gocamJWPPZY)

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<div class="post-metadata">

**Author:** ![KPeter](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/kpeter/32/7644_2.png) [@KPeter](https://discourse.shapr3d.com/u/KPeter)\
**Post date:** [December 9, 2022, 9:40am UTC](https://discourse.shapr3d.com/t/trouble-creating-union-then-subtract/22919/7 "2022-12-09T09:40:44Z")

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Based on the video it seems like an edge of a body which can either be:

- the edge of the beam
- the edge of the body as a result of the intersection if you choose to _keep originals_ in the options of the Intersect tool.

What happens if you move away the beam and the cubic shape, are there any remaining shapes?