I just tried it with no problem. I had one cube then added a small UV sphere in one corner of one face in Object mode. Then I Alt-D the rivet all around the cube face. Then I selected all the rivets and the cube and Ctrl-J to join them all. Nothing duplicated.
I’ve definately seen this. Even just a few days ago with my gate mesh. And, ofcourse, can’t reproduce it now.
edit:
Ok, it seems to have to do with duplicating an already duplicated object. This works for me: from a fresh file (ctrl-x) alt-d the cube and move it aside. Alt-d the allready duplicated cube again and move it aside. Now join the last duplicube with the original cube, you get four cubes in total. Don’t know if thats what the starter meant, or if its supposed to be like that.
Add a Cube and it’s OB: and ME: name will be the same (Cube).
Alt-D Cube and the duplicate now is OB:Cube.001 but the ME: is still ‘Cube’; the Mesh is an Instance used by Both Objects, there’s a 2 in the MeshData.
Shft-D and the duplicate gets it’s own Mesh, ME:Cube.001.
It is possible that i did Alt -D on instances of the original object
and this seems to add new object to the existing set when i try to Joint them.
What can i do against that ?
because i need to copy objects and their original position to the other side of my big cube !
unless i redo the other side one riret by one - But i do have a total of about 50 rivets on one side ( and my object is a little more complicated than a simple cube in terms of faces )