Fusee showing damaged hook attachment point.
FERDINAND GEITNER - A beautiful triple fusee English Bracket Clock, chiming on 8 bells came by my shop recently with what the customer thought was a broken spring. Fusee springs are powerful and more often than not it’s the chain (or line) that breaks but in this case I was surprised to find the pin that holds the hook of the chain in the fusee had ripped out of the brass. The broken section was too far gone to be repaired so the only satisfactory and safe solution was to move the pin to another position along the groove into more “solid” material. It’s very important that the hook be able to freely rotate on the pin. To achieve this I had to increase the depth of the groove in the new position to accommodate the hook.
A diamond-impregnated wheel being used to modify the fusee to provide a new anchor point for the hook
Modification complete showing newly installed anchor pin
Fortunately we have tools at our disposal which were not available when this movement was built. To extend the cutout in the fusee one could use a small diameter circular saw blade which would have less tendency to travel sideways but I used one of my round diamond-impregnated disks on a dental drill. This drill sits very comfortably in my hand. I really like the feel of it as it allows one to apply just the right amount of pressure in the right direction.
The last operation involves the correct and secure placement of the pin. First, I measured the position of the original pin from the edge of the fusee then drilled a hole in the new location ensuring enough material was present to prevent the same failure from occurring. The hole was drilled slightly smaller than the new pin’s diameter. Then using a broach, I tapered the hole from the bottom (the gear side) so if it were to work loose over the years it would not fall out easily. After inserting the slightly tapered pin I gently tapped the ends to widen them for a tight fit. The movement is now in its case keeping perfect time for its owner.
Edge-wise view of the repair
The beautifully crafted movement back in its case ready for many more years of service
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