Elgin Grade 93, Convertible

This is the train bridge from this 16 size Elgin convertible model. The watch had several problems. Here we can see that the upper 4th wheel jewel is missing. It was actually badly broken. In these photos, I have already thoroughly removed the old bits leaving the hole empty. In the closest image, it's the hole at the right that needs a new jewel.

Finding a replacement takes awhile, but it's not an unusual jewel so it's not too bad. The hole has to be the right size obviously, and the jewel has to be the right diameter. But the jewel also has to have the right profile on the outer edge for being bezeled into the plate, and it has to be the right thickness to get correct end-shake (up and down play) on the 4th wheel.

Also, yes, I do this repair the old fashioned way using the tool set shown.

 Done.

 ...And the wheel moves freely.

This watch seems to have been assembled incorrectly at some point in the past. The mainspring was backwards, and in distorted from being (likely) finger-installed. It will be replaced.

This shape is a classic result of improper installation of the spring.

Elgin convertible grades were designed to be assembled in two configurations; either open face, or hunter. This was supposed to save on costs as the factory would not have to create two separate versions of each model. But it didn't really wok out that way as this movements has quite a few extra, specialized, parts and can be tricky to service correctly. The convertibles were eventually discontinued for that reason. Still it's a clever design, there is much to be admired.

Here we see the two layers of the barrel bridge, and the two alternate cut outs, one to the right and one below, for the winding arbor and main wheel. This watch, I am assembling in hunting case mode, with the winding arbor to the right.

The lever setting mechanism used by Elgin convertible grades is significantly different from other Elgins.

This watch had a broken setting lever spring. The remaining bit, and the replacement part, is shown here along with the screw that hold the spring in place.

Most of the lever action is actually on the back side of the movement rather than under the dial. Pulling the lever pushes up a pin that lifts a setting wheel (in the middle of the upper part of the barrel bridge) so it engages a back side center wheel that extends through the center, rather than the winding wheel.

A pin that pushes up through the movement to lift the setting wheel on the other side. I found the pin was jammed inside the hole that is used to let down the mainspring for some reason, instead of where is was supposed to be. At least it wasn't missing. The pin was also bent, but it will still work.

This movement is an Elgin grade 93, 16 size, 11 jewels, made about 1884.  

Find more convertible examples here!