Adjusting an Illinois “Santa Fe Special” 12s Pocket Watch, Part 1: Repairs & Service

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I rarely buy working watches—repairing and adjusting them is the fun part—but sometimes they are broken in quirky and comical ways. When you bottom-feed on eBay, you never know what you’ll get.

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Our current patient on the bench is a rough character: an Illinois “Santa Fe Special” pocket watch. This watch has 21 jewels and dates to 1922. It caught my eye not only because of its eye-catching decoration and high jewel count, but because it is 12-size (grade 274), unlike the more common 16-size Sante Fe Specials.

The seller accurately noted that it didn’t run and had a broken balance staff. I got a good price on it, but I had to brace myself when I saw it.

A few readers have suggested describing repairs and servicing, not just adjusting, in more detail, and this is a good watch to do so with. It’s got problems, people.

Assessing the Carnage

The balance staff sure was broken. Both pivots, in fact, were snapped off. Ouch. But that’s okay—I enjoy staffing, and I happen to have a spare 12s staff.

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But much worse is the hairspring. If you’re reading this blog with small children, you might want to avert their eyes.

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Now that hurts for two reasons. First, I’ll need to replace the hairspring, and that always causes problems in adjusting (see Part 2 for an explanation). And second, a hairspring only gets deformed like that through mishandling. This is evidence that the watch went through some bad hands, which is usually an omen of yet more problems.

Where there are broken balance staff pivots, there are usually cracked and chipped balance jewels. The carnage continued: 3 of the 4 balance jewels (both balance hole jewels and 1 cap jewel) were cracked.

Both lower jewels were hideously cracked.

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The upper cap jewel was okay, but you can see the cracked hole jewel beneath it. The pivot is snapped off in the hole, in fact.

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And as a minor peeve, one of the plate screws is wrong. This model has gold-plated screws, but someone replaced one with a normal steel screw (see the screw next to the serial number on the top picture).

Repairing

wp-1463926641138.jpgThe biggest repair, certainly, was replacing the balance staff. Otherwise, the balance wheel and screws looked to be in great shape.

I’ll do a post soon on how to replace a balance staff. As in woodworking, staffing is mostly a matter of measuring: measuring the pivots, the roller, the endshakes, the tools… But that is for another post. Here’s a picture of the staff I used.

For the jewels and hairspring, I turned to my plentiful stash of 12-size parts watches. Focusing on a particular grade has many virtues—you build expertise quickly, and you end up with a glut of parts.

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Centering the hairspring is crucial whenever you adjust or exchange a hairspring. To do this, you place the hairspring into the balance bridge without the wheel and staff. The hairspring stud should be secure, just as if the balance were installed, and the overcoil should be inside the regulator pins.

Next, lay the balance bridge down and view the balance hole jewel through the collet. The collet hole should be exactly centered over the balance hole jewel. If it is, then the hairspring will be centered when it is installed on the balance wheel. If not, then it will of course be off-center, and that’s bad for positional timing.

The fates smiled upon us, and the spring was nicely centered as it was—no tweaking necessary.

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Servicing & Cleaning Up

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Once the balance staff and jewels were replaced, it was business as usual. Take the watch apart, and then clean, oil, and demagnetize.

The mainspring was replaced with a new white alloy spring—here’s the part number, for the curious. The old blue springs have their charm, but they are either “set” in shape or at risk of snapping, potentially damaging the gear train. We shouldn’t be cheap with mainsprings.

While waiting for the parts to clean and dry, I turned to the dial and case. The dial was grimy and spotted, and it had some dark hairline cracks (look at 7 and 57). I like Dave Coatsworth’s method, described in a PDF download at the bottom of his webpage, for cleaning enamel dials. I soaked this for half a day in Polident denture cleaner. A fizzy denture bath won’t seal a crack, of course, but it will remove the dirt that makes the crack stand out.

Without the contrast between the dark grime and the white enamel, the dial will look sharp.

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Next, the case needed some attention. The case, made of nickel, came with a cracked plastic crystal. Nickel cases are cheap and humble, but I love them because they are easy to polish to a sleek shine.

I took the case apart, spent some quality time with my buffing machine, and got good results. The crystal was replaced with a new glass one. It fit the bezel well, but I used UV-curing glue nevertheless, just in case.

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It’s Alive!

Fortunately, the watch came together nicely—no surprises during assembly. Once reassembled, the movement started running nicely, with a huge amplitude and that loud Illinois tick.

Letting a watch sit is an important part of adjusting. The lubricants and mainspring need to bed in, so I let a watch run at least a day before adjusting it. So, stay tuned for Part 2!