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a problem with boolean operation Difference

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Hello!
I'm trying to create a cylindrical hole in a cube. So I built a cube by extrusion from a plane and a cylinder inside this cube by extrusion from a plane. Length of the cylinder is equal to the side of the cube. So when I apply boolean operation Difference, I expect that the cylinder will be subtracted from the cube and I will see a cylindrical opening in the cube. Instead I see that a thin wall (surface) is left on one side of the cube. How do i get rid of this spurious surface?

4 Replies Last Post 11 nov. 2013, 10:42 UTC−5
Alberto Garcia-Cristobal

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Posted: 1 decade ago 11 nov. 2013, 03:17 UTC−5
HI

I have done similar thing to what you did but with out using 'extrusion'. I dont know why you choose to start from plane (2D) then to construct the 3D (cube and cylinder) while you can 'directly', with out 'extrusion', draw both the 3D cylinder and cube. Then apply the subtraction of cylinder from the cube. I am sure this will work.



Thanks,
HI I have done similar thing to what you did but with out using 'extrusion'. I dont know why you choose to start from plane (2D) then to construct the 3D (cube and cylinder) while you can 'directly', with out 'extrusion', draw both the 3D cylinder and cube. Then apply the subtraction of cylinder from the cube. I am sure this will work. Thanks,

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Posted: 1 decade ago 11 nov. 2013, 09:01 UTC−5
Here I described a simplified situation. My actual geometry is more complex - have a number of prisms which go through the cube in 3 orthogonal directions. So it is easier for me to draw first all these prisms in 2d and then extrude them.
Here I described a simplified situation. My actual geometry is more complex - have a number of prisms which go through the cube in 3 orthogonal directions. So it is easier for me to draw first all these prisms in 2d and then extrude them.

Alberto Garcia-Cristobal

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Posted: 1 decade ago 11 nov. 2013, 10:34 UTC−5
OK


Make sure the 2D plane you started with for extrusion is added in the Boolean operation. May be you added only the extruded geometry !
OK Make sure the 2D plane you started with for extrusion is added in the Boolean operation. May be you added only the extruded geometry !

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Posted: 1 decade ago 11 nov. 2013, 10:42 UTC−5
Alberto thank you!

Unchecking "Keep cross-sectional faces" for each extrusion solved my problem!
Alberto thank you! Unchecking "Keep cross-sectional faces" for each extrusion solved my problem!

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