Subtracting Volume of Mesh from a Bigger Mesh

Hi! I’m fairly new to Grasshopper and I have been trying (unsuccessfully) to use a mesh difference to remove the volume of a mesh from a larger mesh that completely surrounds it. This is how my setup looks like with front, top and perspective view:

Screen Shot 2021-03-25 at 8.36.47 AM

This was my result after performing the mesh difference with these two meshes:

It seems to me that the problem is that the mesh I’m trying to subtract is fully enclosed by the larger mesh and does not intersect it. I’ve tried to make the smaller mesh “intersect” with the outside mesh by drawing a curve, converting it to a pipe, then to a mesh. I joined this mesh pipe to the original mesh like so:

However, when I performed the mesh difference with this joined mesh, I got this:

I’m not really sure what else to do now. I’ll be grateful for any suggestions you might have. Thank you!

please post your grasshopper file with internalized meshes

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My current Grasshopper file is very complicated, so I’ll make a replica with the part I need help with and will upload soon. Thanks so much for your reply! :slight_smile:

Sorry for the wait! Please find attached my grasshopper file and the obj file of the battery I loaded
1.obj (754.4 KB) (16.9 KB)

I think the problem arises from the subraction meshes being not closed

the pipe component has a Cap input where you can select what kind of caps the pipe has by an integer
you will also need to generate a closed mesh for the 1.obj file

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not really easy to do but possible in this case, have a look.
(using weaverbird) (187.5 KB)


Thank you so much! It’s working now.

Thank you very much for your assistance!

Hi again! The grouped components worked for my battery .obj file but did not work for my buzzer .obj file, which I’ve attached to this message. Is there perhaps a more general way to close this mesh? Thanks!

buzz.obj (361.6 KB) (190.1 KB)

for such simple geometries maybe it’s just faster to redraw them from scratch?

buzz_Re.stp (84.1 KB)

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