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Good advice from Stephen. The pivots are actually very soft steel so it’s quite possible one or more has been bent by past mishandling. If that’s the case it should be possible to tap it back to 90 degrees (from all directions) without extracting from the backplate or chassis.
On 9 Sep 2020, at 20:30, Stephen Hibbs <oldtimemachines@...> wrote:
The armature and gravity arm are stout parts, so are unlikely to be bent.
But both are supported by pivots that turn in bushings that screw into the frame from the back and holes drilled into fittings that attach to the front.
First, I’d check for bent pivots and arbors supporting both of these two parts as the likeliest cause of the misalignment you’re seeing. It would only take a little, considering their lengths.
If pivots are perfectly true and not unduly worn, then check the holes they turn in. Decades of running in a dirty environment without lubrication just might cause enough wear to lead to this much misalignment, though I’ve never seen it; there’s very little motion. The gravity arm, particularly, is fairly heavy. Worn-out holes in the front fittings could be re-bushed. Worn-out holes in a back bushing would call for new bushing to be made from scratch. The thread where it screws into the frame might be non-standard. You’d have to dismount the frame from the case and remove the bushings to adequately inspect them. That’s not a frightening task at all. You don’t even have to take the case off the wall. Just be prepared to support its weight when the supporting wood screws come out. A small adjustable wrench will remove the bushings. I do recommend disassembling the movement, leaving the coils and their delicate wiring in place, before removing the frame from the case.
Markleeville, CA 96120
Moving on, the Contacts between armature and gravity arms don't line up with contact being made just on the edge of the gravity arm point. I can't see any adjustment to bring the point of contact to the flat centre of the point where the gap can be set accurately. My thought was to elongate the holes in the copper contact strip but other suggestions welcome..
Also the threaded brass terminal is unscrewing from the frame rather than the knurled nut turning, is the threaded terminal tapped into the frame or secured with a nut behind the frame? I don't want to risk a nut falling off and having to take frame from case to get it back on!