Boolean operation does not work with these objects - Why ? Or how would you do this ?

Hello,
I have been trying to figure out how to cut these out of my mesh. These Shapes were created from extruded curves. I hope to be able to cut holes in my mesh with them. The boolean operation does not cut them out of the mesh like as if they were a cylinder. They are not mesh cylinders though they are mesh objects from curves. Maybe Boolean is not the way to go. Altho the boolean does have an effect if I make my mesh more dense it does not cut them out of the mesh.
Any Ideas ?

<img src="/uploads/default/original/4X/9/e/4/9e43d4069802fffd6d08cf8c77a430c071bbc847.png" width="690" height="358"><br/><a class='attachment' href='/uploads/default/original/4X/6/1/7/617db2d1ee29b32c153b9f595060d2cacae62b37.blend'>BooleanOperationUsingOBJimportObject.blend</a> (698 KB)

Thank you !

Object scales are way off, there’s double geometry, flipped normals, and they’re non-manifold. Boolean works just fine after fixing those

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YOU press TAB at 41 seconds in and it does not go into edit mode ? Also when you are selecting the objects to cut away and they somehow have a box around them and you are pressing tab again and its not going into edit mode. I am confused by that. I am able to get the Manifolds to fill with F but when I press ctrl numpad minus it does nothing. And I dont show the box that is around objects_1.003 Hey thank you for the VIdeo I have learned a lot.
Im missing some little thing.
uptomanifold.blend (737 KB)

JA12 I got it ! I thought ctrl numpad Minus was a shortcut for boolean but?. But I did go in to the boolean modifier and now I am able to drill out with the modifier.

I found this when I searched for ctrl + numpad_minus I found the link below. but I have learned I need to stay away from these things tell I know what is going on better.

https://hardops-manual.readthedocs.io/en/latest/hotkeys/

Nothing weird going on.
“Object scales are way off, there’s double geometry, flipped normals, and they’re non-manifold. Boolean works just fine after fixing those”
so I’m applying the scales, removing doubles, recalculating normals, making them manifold by filling the gaps. After those I added boolean modifier with the help of Bool Tool that comes with Blender, it’s the one that adds the shown modifier with ctrl+np_-.

Thanks JA12 This takes some mystery Boolean operations. And I have a great link to put in my notes.

I-Am-Stupified.blend (872.0 KB)
I am still learning how to make an object like this so I can put faces on it. Not sure what happens here. I did try the things - I’m applying the scales, removing doubles, recalculating normals. maybe it has to do with no even or odd amount of verts and not having a way to do all quads. ? In the anvil tutorial by Andrew he talked about that we needed to have all quads and tris get us in trouble ? I thought about making it inverse and cutting the shapes out of a cylinder with booleen so it had faces.


There’s just one face around, and can’t have that. It’s a severely non-planar n-gon. Curved surfaces need to be described with more geometry, just like a cylinder has more faces around than a cube.


There’s inconsistent amount of geometry around, while still having angles (top). The perimeter is described with too many vertices (bottom).

I-Am-Stupified_ja12.blend (496.4 KB)

The file contains one example of making that with consistent round form and aligned structure for that form, by starting with a curve and then either

  • using the modifiers for the curve to get the round form, then converting to mesh and clean
  • or by converting to mesh, deforming it, and then applying modifiers and cleaning it

Simple deform modifier doesn’t merge the ends, so there’s at least that part that needs fixing. When converting curve to mesh, you want to adjust the resolution so it’s easier to deal with as a mesh. In this case remesh modifier will decide the resolution so it doesn’t matter as much.

There’s wrong terminology in the modeling subforum threads, and Andrew Price isn’t helping.

  • 3D objects have forms, we interpret and model forms, not shapes. A shape is 2D, and in a 3D object shape is its silhouette, which depends on its forms and the viewing angle
  • Just because AP says booleen and has a site called poliigon, there are neither in modeling. It’s boolean, and mesh surfaces are made out of polygons
  • Subdivision surface modifier name in Blender is “Subsurf” by default. That’s not a shorthand for subsurface like people seem to advice in other thread(s). The modifier affects the surface itself, not something below it like “subsurface” would indicate. Correct shorthand for subdivision surfaces is SubD surface, or SDS.

That’s not hate towards AP, although he definitely should know his terminology better, starting from the most basic mesh element that is a vertex, not vertice. More of a disappointment that comes from reading these threads and seeing booleen, poligon, indicating people are not critical enough towards the information they’re receiving. Yes, also question the information I’m giving.

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Finally I have a chance to study this file ( [I-Am-Stupified_ja12.blend ) completely ! This is so cool ! I am going to show pictures of what JA12 did here to fix this problem.

And then this is really cool that you can still edit the curve during the array

I used the UV project to get the image on the faces. I am going to experiment with Marking seams on the original object before the array and see if it carries through.

Very much appreciate this file as I am learning a great deal. So thank you JA12 !

It is still not clear to me why faces work on this and it does not on mine. Does there need to be even number of vertices ?

I can not figure out how

you made the mesh so it would bend with the simple deform right. How did you get the mesh to be like that in the orange ?
thank you !

Beautify faces tool

I am trying to figure out a method to Marc the seams on this curly mesh