Imprint Solid?

 From:  DannyT (DANTAS)
3024.2 In reply to 3024.1 
Hi OSTexo,

Just quickly looking at this, these are the steps that I would take, someone else might have a different approach.

1. Draw your curves on a flat plane above your adapter.

2.Offset these surfaces at your required amount, in this case 0.5mm, use Flip check if offsetting in the wrong direction.

3.Extrude the green curves past the offset surface, the extrusion should be a solid (capped).

4. Boolean diff the solid ribs with the offset surface and delete the bottom parts from the result, you should have something like this.

5. Boolean diff these from your main body and you're done, if you like you can fillet the edges before the Boolean operation.