Ahoy. Having a little bit of a frustrating time with this.
I have a number of vehicle models set out on a turn-table which i want to rotate around the centre axis of said turn-table.
The axis of the turn-table is dead-centre, but when i select the table and the models, the centre-point is offset.
I’ve attached some screen-shots to illustrate my above text.
I think its because the offset is the centre of the selected not just the turntable.
to rotate everything around a specific point i would do either
select the turntable only, <SHIFT-S>, Cursor to selected. Then change the rotation to rotate around the cursor, with <.> this will give everything the same point of rotation
Or you could parent every object to the turntable with CTRL-P (make sure the turntable is the last one selected to make it the parent) then when you rotate just the turntable everything will rotate as well.
Or you could use constraints i think such as the copy rotation constraint. not sure bout this one
Anyway this should help, let me know if i havent been clear or if you need something different
Josh
That one worked just fine for my needs 
Thanks!
