Boolean diff anomaly ?

 From:  svenster
11064.1 
Hi Forum. I'm trying one of Tom Meeks' cool project ideas for a first 3D print (I've linked his project video below). Instead of using text on the globe like example I've imported vector lettering with closed curves. When I perform the boolean difference I'm getting very inconsistent behavior. Sometimes the result looks nothing like it should and other times there are small inconsistencies like the center of vector letters . In my latest attempt ( attached ) the boolean only seems to perform correctly for the first line of the first hashtag lettering instance where the relief in globe is visible either in 3D view or with faces made invisible. As far as I can tell the "200 Working Text" object is consistent and should result in the consistent boolean diff on "000 Working Globe". What am I missing ? Thanks, Sven

https://youtu.be/uJqxvO45gbY