# Subtracting shapes

**URL:** <https://discourse.shapr3d.com/t/subtracting-shapes/16420>\
**Category:** Modeling Questions\
**Created:** [December 18, 2021, 10:46pm UTC](https://discourse.shapr3d.com/t/subtracting-shapes/16420 "2021-12-18T22:46:36Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Technofaux](https://avatars.discourse-cdn.com/v4/letter/t/eb9ed0/32.png) [@Technofaux](https://discourse.shapr3d.com/u/Technofaux)\
**Post date:** [December 18, 2021, 10:46pm UTC](https://discourse.shapr3d.com/t/subtracting-shapes/16420/1 "2021-12-18T22:46:36Z")

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Hi, newcomer here trying to learn some features.I would like to subtract the smaller shape from the disc surface to create a pattern of 3D triangular grooves in the surface. I tried subtract but that didn’t seem to work. I don’t believe I can extrude a 3D shape from another either. Is this possible? Can someone provide some direction?

 ![image](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/2X/8/88dee0816e035cc2f6d705e6ac99c64877d0ffd0.jpeg)

Thanks,  
Bob

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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 18, 2021, 11:19pm UTC](https://discourse.shapr3d.com/t/subtracting-shapes/16420/2 "2021-12-18T23:19:25Z")

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Either you already subtracted the triangle body in which case you can no longer do a **Subtract**. Or, you need to have the triangle body embedded in the larger body beforehand.

If you plan to do multiple subtracts of the same shape, here’s a tip, you can do one **Subtract** and then **Copy-Move** the triangular recesses to desired positions.

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<div class="post-metadata">

**Author:** ![Technofaux](https://avatars.discourse-cdn.com/v4/letter/t/eb9ed0/32.png) [@Technofaux](https://discourse.shapr3d.com/u/Technofaux)\
**Post date:** [December 18, 2021, 11:31pm UTC](https://discourse.shapr3d.com/t/subtracting-shapes/16420/3 "2021-12-18T23:31:00Z")

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Thanks TigerMike, this is super helpful! The copy paste of the subtracted area will help greatly. Thank you again for the help.

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**Author:** ![Technofaux](https://avatars.discourse-cdn.com/v4/letter/t/eb9ed0/32.png) [@Technofaux](https://discourse.shapr3d.com/u/Technofaux)\
**Post date:** [December 19, 2021, 2:00am UTC](https://discourse.shapr3d.com/t/subtracting-shapes/16420/4 "2021-12-19T02:00:54Z")

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Ok I was able to get that to work and I see how you copy the cutout section. I wanted to see what you thing may be the best way to go about replicating that cutout in a pattern radiating out from the first cut, and rotating around the the center hole, maybe every 2 degrees. So, a line of the cutouts would extend out from the center to the edge, then I would want to rotate that line around the disc so that I would end up with hundreds of the cutouts across the disc. I tried to highlight all the cutouts and rotate them around a point then extend that circle outward, but there seems to be a limit to how how much I can copy/move the original cutout. It may be just user error, but wanted to see if you had done anything like this? I see that you are copying the cutouts in two directions, but when I tried to rotate, then go back and copy the rotated cutouts, it didn’t seem to let me re-select them to copy again. Thanks again!!