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In clocks, the pivots (the ends of the gear shafts) rotate in holes in the brass front plate and back plate of the movement. After years of use, these “pivot holes” wear to an oblong shape. To bring the clock back to good condition, the movement should be disassembled and cleaned. Then, the pivots are polished, each pivot hole re-centered, and a brass bushing installed to restore the hole to the correct size. Some repair shops use bad bushing techniques (such as screw-in or Rathbun bushings) to avoid taking the clock apart. 

The clock movement shown here had 16 Rathbun bushings when I received it. I removed these bushings, polished the pivots, installed proper bushings, and did the other needed repair work.

A recent customer has a Seth Thomas shelf clock with a No. 89D 8-day time and strike movement. When it stopped working, he took it to someone who repairs clocks. That repairer couldn’t make it work, and the movement looked like this when I received it:

Part of the repair process is to install bushings to remove the wear that has occurred in the pivot holes (the holes in which the ends of the gear shafts, called “pivots”, rotate). Repair shops that don’t disassemble the movement for repair may use a “Rathbun” bushing, which is a small brass plate with a pivot hole and a screw hole. Each Rathbun bushing is attached with a screw or soldered on. Rathbun bushings have no place in quality clock repair, but were commonly used years ago on American antique clocks when they weren’t worth much. Another bushing system that is even worse uses “screw-in” bushings – these should NEVER be used.

The photo above shows the 8 Rathbun bushings on the front of the movement (the small brass plates secured by the large flat head screws), and the photo below shows the 8 in back.

Notice that 2 of the Rathbun bushings are soldered on, they were probably installed many years ago. The screwed on ones may be have been recently installed.

The photo below shows Rathbun bushings (called by the alternative name Rathburn) in the 1982  clock parts and tools catalog published by S. LaRose.

Here are the Rathbun bushings after I removed them:

A proper bushing is a small brass cylinder with a hole drilled in it. Here are some examples:

Here is the front plate after cleaning and installation of 7 correct bushings:

The completed movement, front view:

Rear view (I made no attempt to remove the solder):

Top view showing the “escapement” (the part that goes tick-tock):

Conclusion

I removed the Rathbun bushings and cleaned and repaired the movement. It now runs like new and will give many more years of service.

Technical Data

Repair job 5898. Pivots polished, new pins installed in 6 pinions, 16 Rathbun bushings removed, 15 bushings installed, strike gears #1 and #2 replaced with good old ones.

This clock has its original mainsprings that are labeled ST for Seth Thomas.

• Time mainspring: 3/4 wide by 0.0165 inch thick
• Strike mainspring: 3/4 wide by 0.0175 inch thick

See more photos.

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This is the Ansonia 5-pillar shelf clock movement. It strikes the hours, and is nominally an 8-day movement, although it will usually run close to 2 weeks on one winding. The plates of the movement are 5 3/4 inches tall and 3 5/16 inches wide. 5 steel pillars secure the front plate to the back plate.

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Many Ansonia shelf clocks from the 1880s have this movement. In the late 1880s or early 1890s, the smaller 4-pillar movement superseded this 5-pillar movement.

The 5-pillar movement has a between the plates recoil escapement using an American-style strip verge (also called the anchor). It has the “count wheel” strike system that requires manual correction if the striking gets out of sync with the hands.

Correcting the Strike

Some clocks have a wire hanging below the dial, near the 7. Push up on the wire from the bottom and release it. The clock will strike the next hour. Do this until the striking is correct.

If there is no wire, use the following procedure:

• Move the minute hand (long hand) forward (clockwise), stopping about 5 minutes before the hour, when the clock makes a striking preparation noise called “warning”.
• Move the minute hand backward (counterclockwise) to 25 minutes before the hour. This will cause the clock to strike the hour.
• Repeat above two steps until the clock strikes one hour less than the hour that the hour hand points to.
• Move the minute hand forward, pausing at each hour for the clock to strike, and set the clock to the correct time.

There is also a “cheater’s method” for correcting the strike:

• Move the minute hand to the next hour (the clock will strike),
• Grasp the hour hand (short hand) near the center and move it around to the hour that the clock just struck. (if the hour hand get loose, push it onto its shaft, using your thumbnails to push in at the center). Note: if the hour hand is too tight to move easily, don’t use this method).
• Use the minute hand to set the clock to the correct time, pausing each hour for the clock to strike.

Mainsprings

The 5-pillar movement has 3/4 inch wide mainsprings with loop outer end. They are ”open” springs (they are out in the open and not contained in barrels). The original mainsprings are rougher than modern springs, and the loop ends are “rolled” instead of riveted. Note to repairers: The keep the original springs in the movement if they have no obvious damage.

If a mainspring needs replacing, I recommend a spring 0.0165 inch thick or less. Don’t use the so-called standard American clock mainspring of 0.0175 – 0.018 inch thick, it is too strong and will result in wear to the mainwheel teeth. I have had excellent results with a loop end mainspring 3/4 wide by 0.0165 inch thick by 120 inches long, such as the 77.303 from R & M Imports or the Timesavers 15959.

Example Clock

The clock illustrated above is the “La Mascotte” , made around 1883 according to the book “Ansonia Clocks” by Tran Duy Ly. I first repaired this example in 2002. I polished the pivots, installed 18 bushings, re-pinned 4 pinions and polished the verge faces. At that time it  had a non-original time mainspring 3/4 by 0.0178 inch thick, and had the original strike mainspring, a rough spring with rolled loop end, 0.0167 inch thick.

In 2012, the clock came into my shop again, with a broken strike mainspring. After cleaning, I observed that the time spring was causing wear to the mainwheel teeth, thus I decided to replace both springs. I selected two springs no. 77.303 from R & M Imports. These are specified as 3/4 by 0.0165 by 120 inches long. Actual measured thicknesses are 0.0157 inch for the time spring and 0.0163 inch for the strike spring. The clock runs very well with these springs, and even thinner springs could be used.

The pivots I had polished in 2002 had caused no wear to their bushings in the 10 years of operation. I hadn’t polished the front strike 3rd wheel pivot in 2002, and its bushing had worn. Thus I polished that pivot this time, and installed a new bushing. No other repair work was needed.

Repair job 5871.

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I thought it would be fun to show all the parts of this movement. In the first photo it has been disassembled and is ready for cleaning. You can tell it needs cleaning by the black deposits on the pivots (the ends of the gear shafts that turn in the holes in the brass movement plates). Many of the parts are strung on wires for convenience in cleaning. Parts such as the hands, chains and hammer heads are not put in the cleaning fluid.

This movement plays Westminster chimes on each quarter hour, and strikes the number of each hour after the hour chime. The time gear train is in the center, chiming on the right, and hour striking on the left. A clock that chimes has about twice as many parts as one with just hour and half-hour striking.

Many of the pivots needed polishing to remove wear, and I installed 19 bushings to correct for wear in the pivot holes.

The movement is labeled at the bottom:

Gravely Furn. Co. Inc.
Martinsville, VA USA
Made in Germany
No ()) Jewels
Unadjusted
PL 85 CM

This movement goes to a Ridgeway grandfather clock.

Repair job 4968.

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I repaired this Junghans W202 clock movement. It has the numbers 33 3 on the back which may be a date code of March, 1933; does anyone know if this is correct?

The biggest weakness of this movement is that the mainsprings are attached to their barrels by tongues cut out of the barrel wall itself. When I received the movement for repair, the time barrel tongue was broken and had been unsuccessfully repaired. The tongue on the strike mainspring barrel broke as I was winding the spring in after cleaning

I made new steel mainspring hooks, drilled a hole in each barrel, and riveted them in. The slideshow below shows the previous repair on the time mainspring and barrel, one new hook I made and installed, and general views of the movement and dial.

The strike second gear had a gear tooth that about to break off. I inserted a new tooth. The pivots needed polishing, and I also installed several bushings in worn pivot holes.

Repair job 4961.

I want to thank Clockmakers Newsletter for their article on repairing barrel hooks.

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I just overhauled a 1950′s cuckoo clock with a Regula 8 day movement.This older movement is different from the modern one, so I am illustrating it here. This movement needed to have the pivots polished and bushings installed. The pivots were not too badly worn, but some appeared to not have been well polished when new.

The case is 18 1/4 inches tall including the top carving; and 15 1/4 inches tall without the top. The overall diameter of the dial is 4 1/4 inches.

The weights are labeled “1500″ and weigh 1545 and 1530 grams. It doesn’t matter which weight goes on which side.

A couple years ago I overhauled my own cuckoo clock with the same movement, that my uncle sent to my parents from Germany in the late 1950′s. It had been unreliable most of its life. The pinion of the time third wheel was very badly worn, so I installed a new pivot, and polished the remaining pivots. It now runs very well.

Job 4640

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