This Seth Thomas electric mantel clock plays Westminster chimes each quarter-hour, and strikes the hour. It has 4 chime rods mounted to a case iron base. This clock uses the General Time M4 motor, which was made from 1948 through the early 1960s.
The date code 11 49 is on the motor and 4913 is on the label (13th lunar month of 1949?).
The case is 24 inches wide and 8 5/8 inches tall. The minute hand is 2 3/8 inches long.
Repair job 5690. This clock had run so long without service that almost half of the first chime gear arbor was worn away by the rear pivot hole. Otherwise, it needed lots of pivot polishing, and 10 bushings. In this movement, the motor winds the mainsprings that drive the chime and strike.
This small round-top Seth Thomas mantel clock uses the no. 48-R round movement, 8-day time and strike with rack and snail striking (so it won’t get out of synchronization). The mahogany case is 10 3/8 inches tall and 7 3/16 inches wide. The white enamel dial has a 4 1/2 inch minute track, and the minute hand is 2 3/16 inches long.
This Waterbury tambour mantel clock was made around 1920. The movement plates are steel that have been given a thin brass plating. Brass bushings were inserted in the plates so that the pivots (steel gear shafts) can turn in brass holes as usual (steel on steel would cause severe wear).
This clock strikes the hours and half-hours on a heavy coil gong. The case is 17 1/8 inches wide and 9 3/4 inches tall. The dial’s minute track is 4 3/8 inch diameter, and the minute hand is 2 1/4 inches from center to tip. The video below shows the clock striking:
When the clock arrived in my shop, the finish had been stripped from the case. I stained it with brown mahogany gel stain, and finished it with spray semi-gloss Deft lacquer.
This movement is a good example of an American clock movement with weak mainsprings. The springs are open (no barrel), 3/4 inch wide, 0.014 inch thick, and about 8 feet long. Many American movements have stronger springs (0.0165 – 0.018 inch thick). A 0.018 inch thick mainspring provides over twice the force of a 0.014 inch thick spring (because the force is proportional to the thickness cubed).
This movement has a strip deadbeat escapement with a very small escape arc (the minimum swing needed for the clock to tick). The running arc is over 3 times the escape arc, showing that the thin springs provide plenty of power for this movement. Unfortunately, it is difficult to find weak enough springs if replacements are necessary. Springs that are too strong will cause wear. The video below shows a closeup of the escapement, and shows the amount of pendulum swing, starting from the minimum:
This Seth Thomas mantel clock from about 1910 – 1920 has an Adamantine (celluloid) wood-grain finish. The movement is marked “89″ and has bim-bam striking on the hour and a single tone strike (the high note only) on the half-hour. The case is 19 7/8 inches wide and 9 1/2 inches tall. The dial is silvered brass with printed numerals and a 4 7/16 inch diameter minute track. The minute hand is 2 3/8 inches long.
I cleaned the movement, polished the pivots, and installed 13 bushings. The pendulum rod and pendulum bob were previous replacements. The clock was losing time, so I shortened the pendulum rod by 3/8 inch.
I replaced the time mainspring because it was causing wear to the mainwheel teeth. I intended to keep the original strike mainspring, but it broke after cleaning and lubrication, as I was winding it into the clamp for re-assembly. The original mainsprings have the following measurements:
Time: 3/4 wide by 0.0185 inch thick (thicker than usual for a Seth Thomas No. 89 movement)
Strike: 3/4 inch by 0.017 to 0.0172 inch thick).
The replacement mainsprings are no. 280-19-003 from Colonial Clock Co., and have the following measurements:
Time: 3/4 inch wide by 0.0158 – 0.016 inch thick by 120 inches long
Strike: 3/4 inch wide by 0.0162 inch thick by 120 inches long.
The movement is a variation on the basic No. 89 having bim-bam strike. It was made before Seth Thomas started giving different model number to variations on the basic movement.
Here is a video showing the pendulum motion and the striking:
This Seth Thomas tambour mantel clock has a heavy brass dial that is engraved and silver plated. It was made around 1910 – 1920. The hands are the modern “ST” style, with the minute hand having an “S” at the base and the hour hand having a “T”. A different style of ST hands were used back in the 1860s.
The case is 19 1/2 inches wide and 9 1/4 inches tall. The minute hand is 2 5/16 inches long. The movement is the no. 89J. It is similar to the standard no. 89, with the addition of a two-piece back plate.
I did limited repair on the movement, cleaning it, polishing a few pivots and installing 3 bushings. Three screw-in bushings had been installed in the past, these are not good to use, but some repairers use them because they could be installed without dismantling the movement. The screw-in bushings are large and ugly.
The original mansprings are the following sizes:
Time: 3/4 x 0.0165 inch
Strike: 3/4 by 0.0161 inch
The pendulum bob is gold painted lead, 1 3/4 inch diameter, weight 5.4 ounces.
This Seth Thomas Adamantine mantel clock is dated June 1918 on the bottom of the case (date code 81F, where F represents the month, and 81 are the last two digits of the year reversed). I’ve seen many examples on earlier clocks where the date code has all 4 digits of the year, but this is the first time I’ve seen just 2 digits.
This later example of the Adamantine case has a simplified design with no pillars or Lion’s heads, and the dial is painted metal. See Seth Thomas Adele Adamantine Mantel Clock for an example of the earlier case design.
Case height 10 inches, width 12.5 inches, minute hand length 2 9/32 inches. The pendulum bob is lead with a brass cover on one side, weighs 5.4 ounces and is 45 mm in diameter.
The original mainsprings have the following measurements:
Job 5577. I did limited repair on the movement: cleaning, polished the worst pivots, installed 8 bushings (correcting 3 that were previously installed off-center), and tightened the strike click rivet.
The model name of this Adamantine mantel clock is “Adele”. When it was new the case was deep red, but it has faded to red-orange. The clock is 11 1/2 inches tall and 12 1/2 inches wide at the feet. The minute hand is 2 1/8 inches long.
The movement is labeled “4 1/2″ on the back, but it is the same as the No. 89 movement. The name “Adele” is stamped in ink on the bottom of the case. There may be a date code as well, but it is very faint.
This Ansonia mantel clock has a black enamled iron case, and was made around 1890 – 1910. It has Ansonia’s 4 pillar rectangular movement that uses thinner (weaker) mainsprings than most other American clocks. This reliable movement was used in many Ansonia mantel clocks.
The case is 10 7/8 inches tall, 11 1/2 inches wide, and the dial’s minute track is 4 1/4 inch outside diameter. The length of the minute hand is just under 2 1/8 inches.
This clock has its original, thin mainsprings: both are 3/4 inch wide and 0.0155 inch thick.
Manufactured by the: Ansonia Clock Co., New York, United States of America
