This particular model can be fixed by running seperate/Flip on these three objects...



First select the large face and choose seperate. Then hit the tab key and type Flip. Then run join on the 3 seperate surface structures to get a solid again... Then select the 2 little cutting solids on this side and run seperate/Flip/Join on them also.. The model will now bool as you expect..

If you look at the 2 solids off to the side here away from the model, these 2 have reversed normals, though "history" is on and the 2 solids opposite them seem to be a mirror result, and the normals on those are pointing in the correct direction..

Possibly this mirror creation method has created the normal bug where it wont get pointed in the correct direction with a proper join??? Because it seems to be in the large piece as well as the small cutting objects

Was this model created in MoI??

Thanks for all your tips!

Yes, this is 100% MoI. I think that Mirror actually *repaired* normals.. but on the second try only, when I mirrored both original and first copy.

Despite all these little snags, MoI is a joy to use. Perhaps even a little bit too easy to use - I can't seem to stop! :-)

Here is a little WIP scene that I created the tablet for; the chair, table, glass and that weird green thingy are from stock Modo content:




Cheers,

Jacob.