# "Flattening" Curved Body For CNC Cutting

**URL:** <https://discourse.shapr3d.com/t/flattening-curved-body-for-cnc-cutting/14370>\
**Category:** Modeling Questions\
**Created:** [August 11, 2021, 8:26pm UTC](https://discourse.shapr3d.com/t/flattening-curved-body-for-cnc-cutting/14370 "2021-08-11T20:26:54Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![ctc1111](https://avatars.discourse-cdn.com/v4/letter/c/a698b9/32.png) [@ctc1111](https://discourse.shapr3d.com/u/ctc1111)\
**Post date:** [August 11, 2021, 8:26pm UTC](https://discourse.shapr3d.com/t/flattening-curved-body-for-cnc-cutting/14370/1 "2021-08-11T20:26:55Z")

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I am drawing a part that will have a ribbed plywood frame on the inside to create a structural frame for the part, which sheets of plywood will be bent over said shape/curves to cover the frame and match said profile.

I have no issue drawing the bent pieces of plywood to match the frames profile in shapr, however since I would like to cut these pieces on my CNC machine, I’m trying to determine if there is a functionality in Shapr, or a clever workaround, where I could “flatten” these bent/curved pieces so I can cut them on my CNC and once I bend them around the actual form, they will fit as they do in the drawing…

Obviously when I “flatten” a curved sheet of plywood in real life, it’s outside dimensions will grow and its overall outlined profile will appear slightly different due to the change in perspective of being flat VS curved.

Thanks for any input and help!

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**Author:** ![mjmnz](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/mjmnz/32/12753_2.png) [@mjmnz](https://discourse.shapr3d.com/u/mjmnz)\
**Post date:** [April 25, 2022, 9:03am UTC](https://discourse.shapr3d.com/t/flattening-curved-body-for-cnc-cutting/14370/2 "2022-04-25T09:03:14Z")

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Did you find a solution inside Shapr3D? I’m working on a plywood boat design and have the same requirement. I think it can be done in Fusion360 but not on my iPad 😞

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**Author:** ![Andrew1](https://avatars.discourse-cdn.com/v4/letter/a/9de053/32.png) [@Andrew1](https://discourse.shapr3d.com/u/Andrew1)\
**Post date:** [May 11, 2022, 1:56am UTC](https://discourse.shapr3d.com/t/flattening-curved-body-for-cnc-cutting/14370/3 "2022-05-11T01:56:08Z")

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Trying to do the same with some sheet metal.

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**Author:** ![ctc1111](https://avatars.discourse-cdn.com/v4/letter/c/a698b9/32.png) [@ctc1111](https://discourse.shapr3d.com/u/ctc1111)\
**Post date:** [June 1, 2022, 1:07pm UTC](https://discourse.shapr3d.com/t/flattening-curved-body-for-cnc-cutting/14370/4 "2022-06-01T13:07:45Z")

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I was compelled to come back to this post to see if there had been any relevant solutions from Shapr3d as I’m running into this issue again.

I am having to CNC cut a plywood flange that matches the sheer line of the boat hull. Obviously the sheer line has various up/down curves that the plywood will easily bend to, but this makes modeling it difficult since following those curves will shrink the length of the part.

Any input on this general issue Shapr3d? @Istvan

Thanks!

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**Author:** ![Wookiee](https://avatars.discourse-cdn.com/v4/letter/w/57b2e6/32.png) [@Wookiee](https://discourse.shapr3d.com/u/Wookiee)\
**Post date:** [August 27, 2025, 1:47pm UTC](https://discourse.shapr3d.com/t/flattening-curved-body-for-cnc-cutting/14370/5 "2025-08-27T13:47:54Z")

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I was able to find that you can export from shaper 3-D into FreeCAD which does have a function that allows you to flatten curved surfaces. But it has been several months since I have visited that issue so I can’t give you more specifics.

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**Author:** ![karesz2561](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/karesz2561/32/33910_2.png) [@karesz2561](https://discourse.shapr3d.com/u/karesz2561)\
**Post date:** [September 8, 2025, 7:12pm UTC](https://discourse.shapr3d.com/t/flattening-curved-body-for-cnc-cutting/14370/6 "2025-09-08T19:12:57Z")

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I was looking for a solution for this today and I came to the same conclusion. I export the part from S3D, import it into FreeCAD and perform this operation there.

https://www.youtube.com/embed/-iKxfOAl9rQ?feature=oembed&wmode=opaque&list=PLufqdowk4Tw9U41f0aeyIGKCR90inXN2L&start=291