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Setting 7750 chrono exactly to 12 position

AP1875

By AP1875
in Watch Repairs Help & Advice

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AP1875 WRT Addict

AP1875

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Everytime I work on a 7750 I have an absolute nightmare fitting the chrono hand back to the 12 position. When the dial has markers all the way around it is very obvious when it is not central. 

I'm using a hand press to set the hands, the red type you see all over ebay. Even with this device pressing straight down for some reason the hand always moves slightly when pressed down. 

I've tried using my tweezers to nudge it slightly but it just springs back to where it was pressed on, I don't t want to nudge it too hard just in case the hand bends. 

 

Can anyone share any wisdom, how I can do this task better? 

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CaptCalvin WRT Addict

CaptCalvin

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I just press the tip of the hand down at the center of the 12 marker with a finger as I push on the plunger. With the hour and minute counters I just adjust the alignment by rotating the plunger as I'm pressing down. Also you might hear some people tell you to hold the reset button in as you install the hands. Does nothing here so save yourself the effort. It does press the hammer into the hour recorder but only the hour recorder, and when you let go of the reset and the brake comes to mesh with the teeth on the hour recorder wheel chances are the hand will be shifted out of alignment.

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AP1875 WRT Addict

AP1875

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1 hour ago, clockboy said:

You need the correct movement holder which allows you to depress the the chrono button whilst fitting. 

1547671549_Screenshot2019-05-1908_16_19.png.ac3d88385fbd0b2d813b11cee6915450.png

I have it but see post above, it's been a debate previously as well, whether that actually achieves anything 

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