I was going to write about Quartz Retrofits but than I came across this. The evil retrofit can wait for tomorrow. I knew this watch would be trouble when I saw the underside of the balance wheel.
I call this Swiss Cheese. The indentations at 2 o’clock are normal. Nearly every other hole has been enlarged to remove weight. I suspect that somebody replaced the balance staff at some point and didn’t have a clue what they were doing when it came time to poise the balance wheel.
Poising the balance wheel: The weight of the balance wheel needs to be evenly distributed so that the center of gravity exists along the axis of the balance staff. Imperfections in manufacturing, the shape of the rivet holding the staff, and the roller are all reasons why it may not be perfect. Upon changing the staff (and moving the roller and reforming the rivet) it is necessary to poise the balance wheel. Corrections are made by removing a small amount of material until the center of gravity is in the center. (More on this when I write about my poising tools). The key word here is a little. One little hole on the underside of the balance wheel will usually do it.
In this case I don’t know what happened. My guess: the balance wheel was not properly riveted and so the wheel was constantly shifting and the individual working on the watch kept drilling holes to try and compensate. Exhibit 1:
The balance wheel is wobbling so bad it is disgusting. I removed the wheel and put it in my truing calipers to fix the problem:
You can see how much difference there is between the gap on the left and the one on the right after rotating the wheel 180 degrees. Turns out the wheel wasn’t bent it is just really loose on the staff and tilted. I guess I’ll have to re-staff it and try poising it. Wish me luck it’s already pretty nasty.
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7 Comments
Dont tell me, The customer swears he never had it serviced and dosent know how that could possibly have happened.
Good find. Really poor previous work that you encountered.
Question is: would it be better to replace the balance wheel with a clean wheel then re-staff. After all, the wheel you show is essentially shot compared to what it should be?
Question regarding another pocket watch;
I am attempting my first watch repair. I currently restore vintage cameras but wish to work on mechanical watches, bought a few books etc.
I am woundering where or if some general repository of diagrams and parts list exists. In particular I have an E. Gluck pocket watch which seems to have a wrist-watch movement. The present company representing E.Gluck stated they do not have information on the older watches.
So where might I look for such information?
By the way, your Blog is refreshing with clear information.
Thank you.
Jay
Jay, of course given the condition of the balance wheel it would be ideal to replace it. Unfortunately this is a vintage Rolex movement and I can’t just call up and order a new balance wheel. If I was fortunate enough to locate one it would probably cost the customer at least $300. In this case I was able to seat the balance better and tighten the rivet. The wheel is now turning perfectly true. I was even able to poise it. It was actually pretty close to being in poise it didn’t require removing much material.
With so much total material removed, will this present a problem with the hairspring adjustment?
Jay,
With so much material removed weight actually did have to be added back to the balance wheel to match the effective length of the hairspring. The fine “watchmaker” who made the holes took care of that already. There were several timing washers on the balance wheel.
Jordan,Hi,
It would really helpful to get a little more detail from you on how you seated the balance and tightened the rivet in this case? Also, have you had any experience of using a balance wrench when truing a balance? Thanks & Regards, Steve.
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[...] be sure that there are no other problems with the watch or you may end up with a balance wheel like the one I wrote about on Friday. There is a good article about this in the latest issue of the Watch & Jewelry [...]
[...] see the lyre calipers in action you can visit my post entitled How does this happen? Truing calipers are one of those tools (like poising tools) that you can pick up inexpensively on [...]
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