Boolean Difference completely deleting target surface

Rhino
1

Hi!
I’m just trying to boolean difference the text in this file to get an engraving on the interior of the ring. For some reason whenever I try it’s deleting the whole inside surface and I’m not sure why.
Any help is appreciated :slight_smile:

File: Example.3dm (16.4 MB)

2

I think the reason is because the letters go through the ring. I reduced the height of the letters and it worked.

2021-10-04_102738
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2021-10-04_102652
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2021-10-04_102632
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