Boolean and combining objects for 3D printing I'm testing some tolerances between Blender 2.83 and a 3D printer I'm trying to combine a nut created with the bolt factory add-on with a cube and have the center be hollow.  How can I do this see image of problem of the center of nut not being hollowed out.  (I tried using the Boolean modifier)
Bolt and cube

After the Boolean operator I can't delete the face in the center of the nut see red arrow (I'm trying to hollow the nut out to test the 3D printed nut threads with a 3D printed screw)
I used the Bolt Factory tutorial and the Bool tool tutorial ad-dons

Pick the object you want to use as a &quot;drill bit&quot; (bolt with threads)
Pick the item you want to drill/place the hole in (box or object) and choose Difference
Note: You could also use Ctrl+Shift+-
(this keyboard combination does bool difference)



Make tolerances for bolt to screw into object

Note: you may want to 3D print the bolt horizontal for strength
3D print the bolt horizontal for strength