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Roskopf balance bushing


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This pocket watch has no hole jewels for the balance staff but simple holes in bridge and base plate material which are made of brass. The balance had a big wobbling especially on the bridge end.

See short video:

Made a domed punch to tighten the holes. The staff pinions are 0.2mm in diameter so i could drill the narrowed holes to the perfect size. Perfect side- and end-shake now, balance is spinning long and freely for a long time, but the shape of the hole is completely different. See picture, left is the original and on the right is the cross-section of the hole after the punching. Now it is a real pain to insert the balance in place since the holes are farther away, the pinions engaging the hole with their very ends. What do You think, can i leave it like that? Or?

Balance bridge cross-section.jpg

 

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Hi SZ,

I was wondering if you can actually fit a jewel in that spot? Otherwise, if it is now working well and you are happy with it you can probably leave it like that. A jewel could be an expensive alternative if bought from a supplier house and you will need 2, up and bottom...also consider the tools for that specific job...

Just my take on this.

Cheers,

Bob

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Thak You Bob! Yes, jeweling excluded, since these none of these watches had jewels here. And as You mentioned, i dont have the proper tools yet.

I have to make a new lifting lever and will try immediately.

This is the ... i think refurbished lever. Or just worn out. Snapshot73.jpg

Should be looking like this:

Lifting lever.jpg

 

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Yeah, that lever looks...how can I put it, not original? I think it should be more....maybe "finished" is the right word? Either way that would be quite an achievement I, at my level, would not dare to tackle.

Hope it all resolves successfully.

Cheers,

Bob

PS. It is possible to modify a movement adding jewels...it is simply an expensive proposition or as you say a detour from the original design.

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