7 Jewel Watches
Melamine dials arose from war-time shortages during World War II. An early laminate made with formaldehyde, dials made from melamine have a flat, dull appearance and surface cracks that will only worsen as the material deteriorates.
Jewels were also used in the escapement. The roller jewel (Blue Arrow), which is mounted on the roller table of the balance wheel, gives the impulse to the pallet fork, alternately locking and releasing the two pallet jewels (Red and Green Arrows), letting the escape wheel rotate one tooth at a time.
Jewels were made from industrial-grade rubies, garnets, sapphires, and even diamonds. They were used as bearings for polished steel pivots that generated very little friction when properly oiled.
are the single most common indicator of possible damage.
Metal (embossed) dials were stamped, milled, or painted, and some were considered railroad grade as Hi-Visibility. Raised numerals, scenic settings, gorgeous patterns, and the fact that they can't crack are the benefits of metal dials.
5. Balance cock screws that are obviously incorrect.
Additional hole jewels can be found on the the mainspring barrel and each train wheel, and then start adding in the extra cap jewels.
Key-wind and key-set watches also didn't meet the railroad requirements. The watch was wound with a small square key through the back and the hands were set by removing the bezel, although a few were able to also set the hands from the back.
Different railroads allowed different watches and had different standards, but for decades accepted an 18-size watch with 15 jewels. In 1891 the terrible Kipton, Ohio train wreck killed several people because an engineer's watch had stopped, and the rules changed.
Open-face was the most common, with the winding stem at the 12:00 position, and was available in every size that American watch companies had to offer. The case had a glass crystal over the dial for easy viewing, which eventually became one of the primary railroad criteria.
Photography transfers also became possible.
All About Dials
Things to Avoid
Hunter (hunting) placed the stem at the 3:00 position, and was not railroad approved. The cases had a front lid that opened by depressing the crown, several hinges, a dust cover, and springs for the front cover and the latch.
3. Balance wheel weights that have been cut off or ground off,
or are mismatched. Meantime screws - the longer ones at the end of the arms - are supposed to look a little different.
Some companies simply milled 'Adjusted' on the plates with no definition of what that meant, while other firms included the total number of positions to which the watch was timed against, as well as isochronism and temperature adjustments.
Adjusted to Positions
Jewel Count Totals
Isochronism The word means "same time" in Greek, and is the accuracy of a watch whether the mainspring is fully wound or almost spent. Barrel stopworks, counter-balanced pallet forks, and longer hairsprings with overcoils all helped to equalize mainspring torque in pocket watches. Early cone fusees didn't have this problem.
All About Jewels
Porcelain-enamel dials were kiln-fired on a copper disc before the characters were added. Single and double-sunk dials were assembled from separate pieces, while one-piece faux dials had depressions milled into their backing plate.
Pendant-set (or stem-set) is the most common. The watch is wound by twisting the crown; most mainsprings can go roughly 40 hours on a wind. The hands are set by popping up the crown, which did not meet the railroad requirements of the day.
Accuracy was clearly the most important aspect of any watch, so high-grade movements were adjusted to keep better time. These adjustments offset the effects of friction and gravity by fine-tuning the balance assembly, and getting a watch to run accurately took many hours of work by a skilled watchmaker.
Conversion dials allowed hunter movements to be used in a standard open-face case by moving the seconds bit to the 3:00 position, returning the winding stem to 12:00. These began showing up after WWI, were generally made of metal or melamine, and could be railroad acceptable.
American watches used the Lancashire gauge, which is based on the dial plate of a O-size (zero size) watch measuring precisely a standard inch in diameter as a starting point, with each ascending size adding exactly 1/30th of an inch.
4. Hairsprings that are missing or obviously distorted.
Winding the watch cranks up the mainspring, which transmits power through the gear train to the escape wheel. The pallet fork meshes with the escape, driving the balance wheel through its arc, swinging back and forth on the hairspring. On every pass the roller jewel trips the pallet in the other direction, letting the coiled mainspring down through the gear train one click at a time.
Fancy dials were also made from kiln-fired porcelain. Each added color meant another trip through the kiln, which made them even more brittle and more delicate. Scarce to begin with, any undamaged example is worth collecting.
Aftermarket dials are legitimate items meant to replace damaged originals, made by Swiss firms like LaRose. The tip-offs are 5-minute markings that are too cherry-red, and dial sinks with incorrect diameters and indistinct edges.
How A Watch Works
2. Balance or plate jewels that don't match the other jewels.
New standards were adopted, and by the turn of the century a Railroad Grade watch was American-made, open-face, lever-set, either 16 or 18 size, a minimum of 17 jewels, and was adjusted for temperature and positions. It was equipped with a steel escape wheel, a micro-regulator, and a bold-font Arabic dial. The most important attribute was that it had to be accurate to within 30 seconds per week.
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If you're new to collecting here are some of the most obvious visual tip-offs for potential trouble before buying the watch.
Temperature Changes in temperature affected both the hairspring and the organic oils in a watch, slowing it when cold. Bi-metallic split (or cut) balance wheels, which expanded or contracted depending on temperature, new synthetic oils, and the invention of alloy metals (Elinvar) in hairsprings in the 1920s all helped to offset this.
That ticking you hear occurs at a rate of 5 times each second, or 432,000 times every single day.
Pin-set (or nail-set) watches were largely a Swiss innovation, and was not an option with American companies. They were difficult to set, because the pin must stay depressed while turning the crown.
Who had the highest count? Illinois, with 26.
Hole jewels by themselves were cupped to retain oil, and relied on the flat jewel face to control endshake (A). Balance jewels and escapements in higher-grade watches also used cap jewels, which trapped the staffs by their pivot tips (B). Capped pairs generate far less friction because a smaller part of the pivot is in contact with the jewel faces.
Most American watches have 7 jewels on the balance assembly - two pairs of hole and cap jewels, two pallet stones, and a roller jewel.
Feet were affixed before the porcelain was laid.
Lever-set watches did meet railroad standards. Setting the time meant removing the bezel and pulling out a small lever, which could be in several different locations around the dial rim. The watch still gets wound by twisting the crown.
6. Plate screws that are wrong or don't match each other.
Most collectors believe this configuration to be incorrect.
Over time the pivots can wear badly, especially with poor maintenance, and once the plate bushings become enlarged the watch is simply ruined.
1. Balance jewels or jeweling screws that have been changed
Positions A watch spends its days oriented pendant up or down, pendant left or right, or the dial up or down. There are a total of nine adjustments - the six positional ones, plus isochronism, plus one each for heat and cold.
Lesser-jeweled watches can be made to keep accurate time, but unjeweled pivots are still bare metal on metal.
The watch still gets wound with the usual method.
Sidewinders are hunter movements in open-face cases. Seldom purchased this way historically, this arrangement means the original hunting case has been melted down.
Winding and Setting