Other PW Gruen "music" pocket watch with Reuge music box

[ANDY YALE]

I was recently given a relatives Gruen pocket watch. It has a built in Reuge music box which I believe is mounted on the watch back.
I would like to know how to remove this particular case back. It will screw about a third of a turn and stop . I am reluctant to put too much force to it lest I break it.
I also am wondering if it is a snap off back.
Any advice appreciated.

 

[RJSoftware]

my GUESS is that it has to be snap off because the winding and on/off is not center. Typical of a music box turn the key backwards and it should unscrew. On some alarm clocks the switch either passes through plate hole or pulls off like a knob and is friction fit. Yours looks to be the kind that passes through. So if it where mine first id try remove the winding key and then pop the lid.

 

[ANDY YALE]

Thanks. I already unscrewed the winding key and removed the switch knob. I'll try a case knife on it and see what occurs.

 

[RJSoftware]

Understand Im not saying 100 certain its not screwback. Also to consider it may even be a tip out style, which the front bezel unscrew and the movement tips out on hinge giving access to 2 case screws to remove movement.

If so, it is IMPORTANT to pull crown out into time setting position or if you see tiny screw below crown unscrew and pull stem all the way out. So, either pull stem outward in time setting position OR pull stem all way out.

If its tip out and you fail to do that you can break stem. Not all tip outs have tiny stem release screw below crown. If you have difficulty tipping out movement its hanging on portion of stem still in move ment. Unscrew the brass sleeve retaining cap and pull out stem. The brass sleeve cap has ribs and is just below edge of crown bottom.

Understand not all may apply to yours, what may appear as crack for a case knife to pop open may not be but artwork. it may be solid. Conversley, what may appear solid can hide a razor thin seam that could unscrew or pop.

The safe move is to check for unscrew back first, then tip out, then pop off.

 

[ANDY YALE]

RJ- I'm familiar with all the variations you note above. Won't have a chance to get at the watch for a couple of weeks.
In the meantime, has anyone else actually opened one of these?

 

[RJSoftware]

Crossing fingers you will post pics of the movement.