Hello Wibbs, any idea what this is?

saccades

A WW1 jump watch?

Wibbs

It's a jump hour watch alright, but I'd place it in the 1920's going by the case and lug design. Very cool. 🙂

saccades

Cheers, it belonged to a mates FIL, just going through his estate (the mate, not me).

Presume you need a horologist to make parts for it?

Mate has no interest but I'm tempted to make an offer.

Wibbs

https://www.boards.ie/discussion/comment/119194116#Comment_119194116

It likely needs no parts, beyond a service and a mainspring, both easily doable for a watchmaker. Unless water gets in, or some amateur goes at it with a screwdriver, or the balance staff breaks(no shock protection in them days) most old watches stop because of things like broken mainsprings or plain dirt and grime. Even a balance staff replacement is doable. Most brands used bought in movements which are common, even the jump hour complication is pretty simple and sits on top like a module of a basic movement.