Boolean creates a hollow object

Question

I am trying to carve out some wear lines on a bullet, from where the barrel of a gun would cut into the metal. I am using a boolean modifier on the bullet, set to difference.

It cuts into the object ok, with the striations / wear lines in the right place, but the bullet is now hollow inside. Is there a better method to achieve something like this?

EDIT: Hollow effect appears when boolean object is close to flat end of bullet.

Have you tried the carve method? Have you tried making the subtraction geometry manifold? — Leander, May 16 '18 at 20:27
Edit above. I checked the bullet and it should be manifold. For the sake of simplicity, I removed the previous boolean object and replaced with a simple torus. It looks like the issue appears when I scale the torus along the Z axis. — BlueHelmet, May 16 '18 at 21:51
Actually, it appears when it gets close to the flat end of the bullet. Any idea why? — BlueHelmet, May 16 '18 at 22:00
I meant the subtraction geometry. It looks as if there could be some non manifold intersection due to the noisy displacement. Upload your file then someone can find a suiting solution. — Leander, May 16 '18 at 22:12
Related https://blender.stackexchange.com/questions/50252/can-i-fill-an-empty-object — Duarte Farrajota Ramos, May 16 '18 at 22:12

score 2 · Answer 1 · answered May 16 '18 at 22:15

Ok, it turned out to be an issue with the original object being non-manifold on the example I posted.

When I replaced it with a simple torus (which was manifold) the error occurred again because there was accidentally an edge split modifier as well. When I moved boolean above the edge split, in the modifier panel, the hollow look disappeared.

Boolean creates a hollow object

1 Answers1