Mainspring arbor removal : repair hints

Arbor Removal:
Some clocks have removable arbors in the mainspring barrels , and some
don’t . Of the removable arbors , there are a number of different kinds with different
methods of removal. Some have a square top that fist in a square hole in the arbor
sleeve. These have a weak point right below the key end and above the sleeve end.
They will break there.
A less common type has a small pin that fits in a slot inside the arbor sleeve
and works against a flat spot in the arbor sleeve. They must be re-installed with this
pin setting on the flat spot. If the pin needs to be replaced be sure to use hard steel.
The type used in the popular European mechanism mechanism is the most common in the modern type of mechanism. It has a slot in the arbor sleeve that must fit in a small
protrusion on the inside of the arbor sleeve. On these types if the mainspring has ever
let go there may be a bulge in the slot that will make it difficult to remove the arbor.
By all means check this and file it down before you re-install the arbor in the sleeve.
On all removable arbors keep in mind that the oil ghat gets inside them can
make it seem as though they are not removable if it gums up over the years. Use a
brass ended punch on the back side of the arbor to remove stubborn pieces or th
check to determine if they are indeed of the removable type. BE EXTREMELY  CAREFUL SO AS NOT TO MUSHROOM THE END OF THE ARBOR.