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A Sicura Automatic Jump Hour Walkthrough


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Boring days passed......

When the Sicura watch and the donor watch arrived, they look like junk.

Yes, I bought a watch with only a mainplate and a rotor and jump hour parts!

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So I can use my Whitney watch that have been in the drawer for few weeks...... It costs me few dollars.

The Sicura shows a BFG 158 31/7 caliber and the Whitney is 158...... They shares the same base movement. Therefore it is possible to combine two calibers into a single jump hour, though it seems strange.

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After servicing, it works like a charm until.......

the jump hour is installed.

Watch stopped?

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It is pretty hard to set the time.

It must be something wrong with the module.

And I noticed that teeth of the date ring is almost missing!

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And the date corrector and yoke......

I browsed the intercharge list on JulesBorel. These also can be found from BFG 582.

But both are rare calibers in Chinese market......

I am searching Internet......

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A day-date BFG 628!

From the technical document on Cousins, parts I need (2566, 2566/1, 2557/1) look like the same.

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So I bought this immediately and I am waiting for 4 days delivery......

Continued

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  • 3 weeks later...


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