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repacing a balance staff


gary17

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hey guys

I have removed the balance staff using the staking set. I measured it and its supposed to be 417mm total length and it was 408 mm so near enough it did have no pivot at one end and the other did not like being forced out. How the hell you measure each individual little part of it was beyond me so i ordered the 417 mm one.( It looked the same.) 

Now i am left with 1 problem. How do i re-assemble it when i get the staff with just a staking set. Oh and the trusty hammer. 

The videos on the subject on youtube, they all seem to use specialist tools which i do not have.

Please someone tell me it is possible.

cheers

gary

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39 minutes ago, gary17 said:

hey guys

I have removed the balance staff using the staking set. I measured it and its supposed to be 417mm total length and it was 408 mm so near enough it did have no pivot at one end and the other did not like being forced out. How the hell you measure each individual little part of it was beyond me so i ordered the 417 mm one.( It looked the same.) 

Now i am left with 1 problem. How do i re-assemble it when i get the staff with just a staking set. Oh and the trusty hammer. 

The videos on the subject on youtube, they all seem to use specialist tools which i do not have.

Please someone tell me it is possible.

cheers

gary

You take all measurement using a caliper or micrometer. See photo below and the diagram I posted earlier: several diameters and length. Your staking tool is what you need to install the staff. Then of course - watch balance truing and poising steps, which require special tools.

IMG_1142 - Copy.JPG

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15 hours ago, rodabod said:

I think Mark did an excellent video showing how to create the rivet on a balance staff. 

Mark use a Platex but the principle is the same . I use the same method. So far it has worked fine. I cracked a balance wheel some time ago. But not sure it was my fault. 

 

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I am "hammering" one right now! Elgin pocket watch.

Another tip: do notice roller's and hairspring stud's position in relation to balance wheel. Usually someone already made orientation marks to simplify life for you. Good people... kind, friendly ?

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1 hour ago, gary17 said:

Thanks for the tips guys i will let you know how i get on.

cheers

gary

Hi Gary, as promised, i will try to demonstrate how I do this operation:

- remove hairspring and roller (make some mental notes, or use marker, or observe existing marks showing orientation)

- punch out the old staff, preferably without cracking and warping the balance wheel

- note Staff diameters on both ends to select right stumps / punches. I have just riveted new staff for Elgin pocket watch using two punches, which were 0.01mm larger than staff dia: K&D round punch #89A and flat punch #59A, both 0.81mm hole dia.

- center / align your stump and punch (i used an old Staff to confirm concentrically when everything was centered with #1)

- place new Staff, mount the balance wheel on top

- get your round end punch and bring the hammer of your choice! ?

- repeat previous stem with flat (gently)

Staff-- - Copy.PNG

IMG_2012 - Copy.JPG

IMG_2006 - Copy.JPG

IMG_2014 - Copy.JPG

IMG_2019 - Copy.JPG

Edited by Poljot
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