Since it doesn't seem like there is an existing topic on this, how are people approaching painting turrets on the battlefield support units (or the Goliath)?
The easy approach would be to glue them in place before priming if you don't care about them moving. I wouldn't recommend priming without glue as some of the turrets are loose enough to break any fix the primer may provide and result in potential chipping/flaking.
Approach two would be to remove the turrets and paint both parts separately. In general this should be straightforward enough, but does lead to a few questions:
-turret removal/replacement: with almost every unit I have the turret is easily removable by hand with little force. The exception to this has been the Sturmfeur, the Maxim, and the Galleon (the latter two being small enough I'm still not sure what type of connection is being used as I haven't gotten them off), and the pintle mounts on the Sturmfeur and the SM5 (same issue).
-Once off, there is the question of what to paint/not to paint: some units have contact points where there will be definite rubbing, while others the turret floats on the ball socket and can get moved in a way there will be unintentional rubbing between the turret and the chassis. Anything never-visible can be marked and left unpainted, but is a heavy clear coat enough for painted areas exposed/covered as the turret gets rotated? Are there painting techniques that would help blend any friction degradation of the paint?
-Reassembly:assuming the ball and socket are properly masked and left unpainted, a light coating of floor polish such as future (or whatever it is called these days) should probably be sufficient to hold things together while allowing free rotation. I know some people prefer to coat the ball with a layer of glue and attach after it has dried, but future has always been sufficient for small plastic joints where I've needed it. Has anyone attempted either or alternate methods so far?
Another method I've seen mentioned briefly is replacing the ball and socket with magnets, but I don't have any experience with small RE disk magnets to know if there are any potential issues with polar conflict while rotating, or proper sizing (since there are at least three different socket sizes in use).