I have a thin box (all I did was create cube that I scaled in one direction, then subdivided the mesh) that I would like to break into pieces using the Cell Fracture tool:
When I run Cell Fracture - for example, splitting the box into just 3 pieces, but same thing happens with more pieces as well - the resulting fractured pieces seem to form a hollow box with empty space inside:
Ensure you have no modifiers applies to the mesh
Ensure you have no duplicate faces in your mesh
Ensure you have no internal faces in your mesh
Basically all you need is a extruded plane. Looking at the edges of your model this does not seem to be the case.
You have failed to supply a link to your blend file (why ???) so you will have to check this yourself. Or just delete what you have and add a cube to your scene and scale / subdivide.
all I did was create cube that I scaled in one direction, then subdivided the mesh
Doing a simple subdivide operation would not give the result you show so what did you do exactly ?
I apologize for not including a blend file before. In this post I have attached a blend file that demonstrates the issue (let me know if there are any issues with the file).
In this file (created just a few minutes ago from scratch), I made three Cubes and rescaled each in the x direction. From there:
– For the leftmost cube (Cube.002), I added a triangulation modifier, then added Subdivide, then ran Cell Fracture with number of source points = 3 and noise = 0.1 (all other parameters default)
– For the center cube (Cube), I added Subdivide (no triangulation), then ran Cell Fracture with same params as above
– For the right cube (Cube.001), I did nothing after rescaling, and then ran Cell Fracture with same params as above
The second layer in the blend file shows the results (I’ve cut away one of the pieces in each fractured cube). The fractured versions of Cube.002 and Cube look correct, while the fractured version of Cube.001 looks incorrect. Do you have any ideas for explaining the differences in these results?
In any case, it looks like I can get the results I want (e.g., with the left two cubes), so I suppose there may have been something wrong with the original blend file I was working with - I can just use one of these good cubes I’ve made in the new, attached blend file - but I’d still like to understand a little better why this “bad” behavior can happen with Cell Fracture. Thanks again!
After fiddling around with my scene for a while longer, I think I realised the issue I was having. In the cube where this problem was occurring, one of the scales (in x direction) was negative, so the normals were inverted (and doing recompute normals didn’t fix it). By either flipping the normals or flipping the sign of the x scale, the cube fractured with the desired behavior (no holes/hollow region). (For the record, it worked after scaling, triangulating, and subdividing, then fracturing, just as I was hoping to do.) Thanks again!
