Making a Winding Wheel

The wheel on the left is a "repaired" winding wheel form a Jaeger LeCoultre A-10 aircraft clock.  These clocks do not have a clutch that prevent s damage if the winding is forced backwards and these clocks wind counter clockwise, the opposite of most timepeices.  So the windng wheels are often found with broken teeth or the winding stem is broken.  As you can see, a previous attempt was made to "repair" the wheel by letting in new teeth.  Since these it is nearly impossible to replace so many teeth with the correct proportions by hand, the winding action was rough and inconsistent.  Parts are not available and new one had to be made.  The prepared steel blank is on the left.

The blank is mounted on an arbor and put in the horizontal mill for cutting the teeth.

Spray lubricant to protect the cutter.

Unlike brass wheels, steel winding wheels have to be hardened and tempered.

Here is the finished wheel on the mainspring barrel next to the "repaired" wheel.  Operations not pictured were punching the square center hole and running the wheel through the surface grinder to bring it to the correct thickness.

This is what the setup looks like.  You can see the set of dividing plates to the left of the cutting set up.  The correct dividing plate is mounted on the rear of the headstock.  Dividing plates are discs with accurately located notches evenly spaced around their circumference.  Different numbered plates allow you to cut gears with different numbers of teeth.  Most sets go include plates between 50 and 100 divisions.