Kingston Test Assembly: Part 3A
Finally the dial is on the movement!
The hands have been set and have been checked for alignment with the dial and clearance between the hands.
It’s more than just a nod to nostalgia. The hands here are curved toward the end because the hands have to clear the interior surface of the crystal. To get the thickness of the overall watch right I designed the crystal to be closer to the dial than normal, hence the “curved” hands.
Here is the process for hand cutting the stem. First is a rough cut with a pair of pliers. It leaves a rough end that won’t screw into the crown properly.
Here is the stem half-way through the filing. Normally all of the stems for the custom watches are cut and finished by hand to get the optimal length for each watch. In this case, as is the norm in watchmaking, several hundredths of a millimeter make a big difference in the action of the crown.
The finished stem…or actually not quite. This stem ended up a little on the long side. It required a little too much effort to screw down and onto the case tube. Over about an hour I trimmed it down little by little. Finally I got to the point that the stem as slightly too short. The way you can tell is that the crown begins to wind the movement again when it is close to bottoming out on the case tube.
One night, and part of a morning later, I was able to install the finished stem. It wasn’t too far off the original number I had from working the case samples but the adjustment was worth it and I learned some more valuable information about this style of case tube/crown assembly. I expect working with this assembly will get easier with time but it’s not as simple as the standard dual gasket assembly that is featured on the rest of our watches.
I only had time to post the first half of Part 3. I didn’t mean to jerk everyone around but I am trying to give current orders and getting the Kingstons ready to go to Switzerland for assembly priority over the updates. I will post the final part by Monday. I have to get some watches shipped on Saturday. I spent much of the first half of this week working on preparation for the Kington assemblies and have been neglecting custom watch orders.