Solid difference used to work in the same file, it doesn't now

I used the solid difference in the same file and it worked perfectly fine. Now I made a small change to the inner geometry and it doesn’t subtract them anymore. Why is this the case?

Test.3dm (7.5 MB) (4.6 KB)

Hi @kiana.mousavi,

The four ornate pieces are completely enclosed by the rectangular block and rhino needs a surface intersection in order to do a difference (Rhino being a surface modeller, not a solid modeller).

To make the difference work you can split the block into two blocks:

(not forgetting to cap them if you use split).

Or you can add a sprue to the bottom of each ornate piece, extending outside the box:
If you make these from a cylinder with a microscopic radius they shouldn’t show up in a 3d print.

Or you can adjust the ornate pieces’ positions to get intersections with the box surface(s).