Profile cover photo
Profile photo
Jeff Sexton
33,399 followers -
Neque porro quisquam est qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit...
Neque porro quisquam est qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit...

33,399 followers
About
Posts

Post is pinned.Post has attachment
Welcome!
Add me to your Circles and learn about mechanical timepieces and how they work, the history of the American watch industry and especially all about the Elgin National Watch Company! Check back for new content daily!

https://plus.google.com/+JeffSexton/posts

And for more, check out these:
http://www.elgintime.com/
http://elgintime.blogspot.com/
http://instagram.com/elgintime

Do you have a vintage watch to be serviced?
Maybe I can help. Take a look here, http://www.elgintime.com, for information - specializing in Elgin, Hamilton, Waltham and other antique American makes. Contact me at jsexton@elgintime.com with any questions.
Animated Photo
Add a comment...

Post has attachment
Add a comment...

Post has attachment
Job Number 180062
Testing...

#Waltham   #pocketwatch  
Job Number 180062
Job Number 180062
elgintime.blogspot.com
Add a comment...

Post has attachment

Post has attachment
Outbound today, job number 180040...
Photo
Add a comment...

Post has attachment
Job Number 180055 - Answer!
Here's the explanation for this watches problem:
https://plus.google.com/+JeffSexton/posts/edrqqh5VMMW

Watches are machines, they behave in completely deterministic ways. The key elements of a watch are a power source (mainspring), the gear train, an governor mechanism (escapement and balance), and an output (the hands). The gears are not arbitrary, they have to have specific ratios to each other in motion. For example, there are 60 seconds in a minute. So the 4th wheel, that carries the seconds hand, has to go around 60 times exactly for each single revolution of the center wheel, which carries the minute hand.

The exact speed of these wheels, what we think of as the watch's accuracy, is a function of the escapement. But the wheels must turn at the appropriate rate relative to each other for minutes and seconds to be even meaningful. Gear ratios dictate this relationship.

Sometimes, when a watch is running fine, but reading incorrectly, the degree of error can tell you exactly where the problem is. You don't even have to see the watch.

This watch gained 22 minutes per 24 hours. There are 64 teeth on the center wheel (typical of American pocketwatches). The passing of each center wheel tooth against the pinion of its neighbor, Mr. 3rd wheel, represents 1/64th of a minute. 1/64th of a minute error per hour (each turn of the center wheel) adds up to 22.5 minutes error in 24 hours.

Inspection of the center wheel reveals that I missed a slightly bent tooth. Each time this part of the wheel came around, it was not enough to stop the watch, but it did pop over to the next tooth, skipping exactly one, per hour. The problem is visible in this image.

Fortunately, the damage to the wheel was not severe. I was able to nudge the tooth careful back to its correct position, so the center wheel would turn smoothly.

The lesson is not to get lazy about checking each wheel, especially on a watch like this that did have damage to the train to begin with.

#Elgin #pocketwatch
www.elgintime.com
Photo
Add a comment...

Post has attachment
Job Number 180062
This one has been straightforward, so far.

#Waltham   #pocketwatch  
Job Number 180062
Job Number 180062
elgintime.blogspot.com
Add a comment...

Post has attachment
Job Number 180055 - Quiz!

Since the last one was so popular, here's another one...

This watch went together really well. On the machine, it rates near flat line and almost no beat error. I had high hopes. But in practical tests, it reads really fast. The watch gains, reliably, 22 minutes per 24 hours.

What is the problem?

I'll post the answer later, here:
https://plus.google.com/collection/QZOEnB

#Elgin #pocketwatch
www.elgintime.com
Photo
Add a comment...

Post has attachment
Job Numbers 180057 and 180055
In progress still...
Add a comment...

Post has attachment
Job Number 180057 - Answer
Here's the rundown on this post:
https://plus.google.com/+JeffSexton/posts/FyYQZbJ6abk

It's missing a sliding part that would fit between the index and the screw. This part would have teeth on one side so that turning the screw would cause it to move from side the side, taking the arm of the regulator with it.

The thing is though, that I think they sometimes shipped them like this, with the part missing. I have seen others missing this part, having no marks or other signs that it was ever there. If you do an image search and look as close as possible at other movements, a lot of them look like this. This is personal conjecture of course, but when you work on these early American products they really feel like the products of factories that operated in a pretty frantic, ad-hoc manner.

Aurora used, I don't know, 5 or 6 regulator designs, and held valuable patents on them.

#Aurora #pocketwatch
Photo
Add a comment...
Wait while more posts are being loaded