I recently had a client inquire as to why the minute hand on his watch always seemed to trail the second hand by half a minute or so whenever he set the time. This can be a common problem, particularly on mechanical watches because they need to be set more often. Most people either don’t notice or don’t care, but some do. For who do, this post is for you.
The cause of this problem is due to a necessary amount of play between the teeth of the gears that drive the hands. The horizontal play allows the gear teeth both freedom to move and prevents them from binding. You can sense this play when you turn the crown gently back and forth. When you do so, you should be able to note a fraction of a turn when the minute hand does not move after a change in direction (clockwise to counter-clockwise and vice-versa). This play of the minute hand can equal as much as a 30 second sweep of the second hand – as my client noted. The key to eliminating the delay of the minute hand starting to move after the time has been set, is to ensure that there is no clockwise play in the gears when the crown is pressed back into the watch.
The means I use to ensure that the gears are fully engaged when I set a watch before returning it to a client, is to move the minute hand roughly 5 minutes before the desired time and then moving it clockwise to precisely the position that I wish it to be in when the watch starts
Be certain not to move the crown counterclockwise when pushing it back into the watch as this will disengage the gear for the minutes slightly again and cause the same error.
Watchmaking Books on Lulu
4 Comments
That’s exactly what I do.
I think you mean to move it clockwise ahead of the minute that you want and then move the minute hand back counterclockwise to the minute marker that you want. That is what I do and it works very well. I also neutralize the crown so that is not engaging the gears when I push it in; otherwise it may move the minute hand when it is pushed in.
Hi Jud,
I have a feeling that you may have missed the intent of my post. The reason for ensuring that the gears are fully engaged and not “neutral” when then watch is started is to make certain that the minute hand begins to move in synchronization with the second hand. This would not be the case if the crown were neutralized.
I have to agree with J. Edwards here. You want the gear train engaged in the direction the hands will be moving so that any slack from the gears will be eliminated. As for when you push the crown in you just have to do it carefully so it doesn’t rotate as you push it in.
If you do it the opposite way the second hand continues ticking but the minute hand doesn’t advance until the slack in the gear train is taken up which can lead to a dragging minute hand.
Of course, the higher grade the watch the less slack there is in the gear train.
Post a Comment