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Classic watches, watchmaking, antique tools, history, vintage ephemera and more!

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.

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Elgin Grade 303

This watch had a broken staff. Here we have the hairspring and the double roller removed from the broken staff. While doing this, I found that the roller jewel, the red (ruby) pin on the roller table (at the right) in this image, was loose. It was still in place, but the shellac that holds it was broken away. Lucky it didn't get lost so it can just be reseated.

This is the roller jewel from this 12 size Elgin pocketwatch. It gets cleaned up so that no old shellac or other grime remains and then reseated in the roller table. The roller is a 'D' shaped length of synthetic ruby. This material is hard and smooth enough to take the stresses of its roll in the watch escapement without wearing down.

The roller table is held in a special warmer. The roller jewel is placed in a 'D' shaped hole in the roller table and a tiny amount of shellac is melted to hold it, using an alcohol flame.

The warmer has a long square end opposite its jaws. The long end goes into the flame and heat is transmitted slowly to the roller table, and to the shellac, at the other end.

When it is just right the shellac flows. The roller jewel is moved up and down in the hole, with tweezers, to coat it, made perfectly straight and true, then allowed to cool. It is a bit tricky keeping the temperature right. Too hot and the shellac will scorch and be ruined. Also it is critical that the jewel be situated exactly right. It is usually necessary to soften the shellac and adjust the jewel 2 or 3 times.

Only a tiny speck of shellac is needed. I have been using chips off these pieces for ten years.
Here is the roller jewel secured in the double roller table. This then gets friction fit to the lower side of the balance.

But this watch also need a new balance staff.

Using the lathe, the hub of the old staff is cut down to almost, but not quite nothing.
The remaining little ring of steel is popped off with this setup, in the staking tool. This is the only safe way to remove a broken staff without risking damage to the arms of the balance wheel.

 The new staff is riveted to the balance wheel.

Another step is using the truing calipers to make sure the balance wheel is perfectly flat and round. The hairspring is then installed and it's all set.
After assembling the hairspring and roller table with the balance...


 
This dial is called a "peacock dial". It is a painted metal design that for whatever reason has not held up well over the decades. This one is pretty typical. The paint is fragile so surface cleaning has to be very gentle. In fact, at the time, both Elgin and Waltham recommended not cleaning this type of dial, at all.

When the hands are re-installed it is important to make sure they are flat and level, and get their height correct, otherwise they can interfere with each other and stop the watch. So of course the clearance has to be checked all the way around. In spite of this, sometimes, things move a little over actual run time. The hands touch and stop the watch during testing. This rarely happens, but it does, and when it does it has to go back, get readjusted, and the test cycle starts again from the top. 

Once in a very long while, I have a watch that inexplicably does this multiple times. This one is on its forth!

These old watches are not perfect, far from it. The leading cause for an issue like this is probably that the old plates leave the center shaft, the cannon pinion, or the hour wheel not exactly vertical. Then in certain combinations of the positions of those parts during their rotation, you have a problem. Gravity is also a factor, which is one reason watches get tested in multiple orientations.


This watch is Elgin's grade 303, 12 size, 7 jewels, made about 1926

It is actually a repeat visitor. It was serviced a couple of years ago too.


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