I am trying to subtract the big ring (highlighted in light orange) from the smaller ring (highlighted in dark orange) so that there is a slot down the middle of the smaller ring.


I have tried every combination of Boolean modifiers, and they do not work. In the past, Difference sometimes worked to subtract geometry, but not always.

This is what happens when I apply a Difference modifier to the smaller ring and target the larger ring:

failed difference

As you can see, almost all of the ring is removed, except for a few tiny bits on the sides. I have no idea why this happens.

This is not the first time Difference has failed me, for seemingly-indecipherable reasons. Is there a way to force Difference to work logically, or, failing that, to subtract geometry another way?

  • $\begingroup$ it looks like you have quite a lot of self-intersection geometry on the upper and lower parts of the pitchring. if you view it using Z to see through the mesh you'll see some parts much darker than the rest. $\endgroup$ – zeffii Jan 6 '16 at 21:00
  • $\begingroup$ probably difficult to see, but also there's a small shell / thickness going on in the pitchring, which seems also to cause self intersection.. -- zoom in real close $\endgroup$ – zeffii Jan 6 '16 at 21:04

enter image description here Please consider

  • Adding loop rings to the circular form.

  • Select the middle faces. Extrude - No Movement Accept. Shrink Fatten. You may Shrink Fatten to create a cut out slot.

enter image description here

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.