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Inside the Best Replica Rolex Daytona |
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Articles -
Watchmasters Corner
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Written by Ziggy Zumba
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Page 3 of 4
Question: What sub-dial is running all the time and has the most potential for
wear and should be jeweled to reduce wear???
If you answered the “Running seconds at 6
sub dial” then your right!
So then why in the world would you choose this one to NOT
put a jewel into??? Any of the other ones, not a problem, no jewel = not a big deal. But the
one that is running all the time, and you have brass on metal for a pivot point?? The only
other location where there is metal on metal is the mainspring barrel, and it moves a complete
rotation every 8 hours or so, not once every minute.
This is the pivot for the running
seconds gear:
It’s not a question of will it fail, I
think it’s a question of when will it fail And when it does, or the drag gets too high
for the movement to be able to swing out really well, then the watch will stop working.
Biggest design flaw in an otherwise well made modification (the large gear on the center post
is not a design flaw, simply a point of extra drag).
6 position, the biggest mystery
of them all solved!
If you remember my comments on first seeing this movement,
I asked how the 12 hour counter could be moved from the 6 position to the 9 position. My
biggest issue was the overlapping of the gears (moving motion from the 9 to the 6 dial
position, and from the 6 to the 9 position), which as we saw was solved by taking the running
seconds and sending it across the dial face, through the middle of the movement, and to the 6
O’clock position. With those gears out of the way, the space is now cleared to get the 12-hour
sub-dial into the new location.
The original 12 hour counter works as
follows: the gear is actually two pieces, the bottom half is connected directly to the bottom
of the mainspring barrel and it turns ALL the time, even with the chrono stopped. The top half
of the gear is driven through a clutch. In the chrono stopped position, there is a small brake
lever that rests on the side of the top half of the gear and holds it locked. The gear also
has a heart piece cam on it, which serves to center the gear when it’s reset.
It’s
simple to take the top half of the 12-hour gear, add two more gears, and reposition the 12-hour
counter to the 9 position on the dial.
The problem of having the brake and reset to
zero levers moved across the dial face is solved by retaining the original ones, since the top
gear is connected to the new gears, then resetting the chrono will in turn reset the new gear
as well (pretty clever).
Some have reported problems with the 12-hour sub dial; from not
resetting to 12, to running all the time. Not resetting to 12 is probably due to a loose hand
(not uncommon on chrono’s), or the gear slippage from the original gear to the new ones.
Because I did not have a chance to disassemble the movement, I can only assume that a new gear
was installed over the old one, not sure if that is the case, but if you look at the “teeth” on
the gear here,
they are not really gear teeth, but notches
for the brake to rub against and stop the gear from moving. They may have substituted a new
gear for this one with the clutch built in etc, no way to know until it’s opened further (which
was not done with this one).
As for the people with this model and it has the 12-hour
running all the time, that is simply the brake lever being out of place on the arm from the
bottom pusher. See the picture here to see how it sits in the notch, easy to assemble the
watch with it out of place.
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Last Updated ( Tuesday, 14 August 2007 )
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