This series shows the
making of an arbor for the mainspring of a chronometer. The
process is the same whether for a chronometer, clock or watch.
This particular project shows the virtues of the Habegger lathe and the
vertical mill. While it could have been turned in the 10mm Levin,
the Habegger's increased rigidity made it the better choice. I
remember using the Levin ad the small 3 jaw chuck to make similar items
and it was headache. The Habegger 102 turns a 3 hour chore into a
one hour joy. This is why I sold the bench mounted Levin very
shortly after I acqured the the Habegger. This project also makes
use of the vertical mill for two operations. again, I could have
filed the square on the WW lathe using the file rest and I could have
drilled the hook hole in some other way.
this arbor break? While out of its case, it is easy to mistake the
mainspring arbor and setup pawl as the place to apply wind over the
fusee arbor. Given the hardness of the arbor, it does not take
much to snap off the square. Many owners mistakenly wind the wrong
arbor when the have the movement uncased for examination or for removing
the wedge that immobilized the balance during storage or shipping.
the various diameters on the 8 inch Habegger.
turned blank compared to the original.
next few shots show milling the square for the setup ratchet..
the hole for the mainspring hook.
the blank is mounted in the 10mm Levin for polishing prior to heat
treating. the pinion is cut.
to tempering and final polish.