Grandfather Clock Moon Gear Installation
Grandfather Clock Moon Gear Installation
Grandfather Clock Moon Gear Installation is as follows. The moon phase function is only run by one gear. The gear is called a Moon Gear and sits behind the dial, on the same tube as the hour hand. It is easy to remove by loosening the one set screw and it will slide off.

It gets put on the new movement at close to the same place it was on the old one. Trick is to only have it align with the gear behind the dial that is to engage with it. As long as the two are engaged that one moon gear will spin the gears on the back of the dial and turn the phase of the moon slightly over time.
If the clock were to stop after a short time with the dial on, it is possible that moon disk is not turning freely. This is of course not the fault of the movement, but in the dial alone. The lunar disk is like a saw with the teeth, there is a flat bar that keeps it from spinning more than one tooth at a time. This friction press flat piece a brass or bronze material should not put alot of force against the moon disk. It does not need to take monster truck force to spin that disk, the bar is only supposed to stop it from spinning more than one tooth at a time as stated.
The adjustment for this if it were to happen is to just bend it back some so there is not as much tension.

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