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Posted (edited)

Hi

I'm thinking of ordering a standard hand set for a valjoux 7734, as original ones are not easy to find. How much can I deviate in tolerance from the original diameters? An original Hour hole is 1.4 mm and minute hole is 0.95 mm - can I go with 1.5 mm/0.95 mm respectively from Cousins? Or should I always find a smaller one in diameter and somehow "file" it larger?

Kind regards

Khan

Edited by Khan
Posted

My advise would be go smaller. Better to open the hole then try closing it, You don't have much thickness when it comes to closing. Just be very careful when opening the hole, the most difficult I found was holding the hand, even with proper hand holding tweezers it is hard, a little lube on the broach will help. 

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Posted

For me, it depends on whether the hands have an actual collet to grip the wheel/pinion as sometimes they will split if you try to broach them open. I usually close them down with a jewelling set. If you don’t have a jewelling set then I’d just try broaching smaller ones open though. 

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