It’s really important to keep your fine mantel clock in excellent working condition and appealing to the eye. Here is an article I found that you may find helpful: http://www.higglehaggle.com/tips-in-caring-for-antique-clocks/

Keep on ticking.

So, how do we stop the weight, string and axle from accelerating?

 

 

We attach a gear to the axle which has the string and weight attached to it. The gear has teeth, but the teeth are not symmetrical. One side of each gear tooth is tapered, looking like a “ramp”; the other side is cut somewhat straight and mostly aligned with the center of the gear. This is the “escapement gear” (you’ll see why it’s called that later). The escapement gear is attached to the rod, and it still wants to pick up speed as the earth’s gravity pulls down on the weight and string. We still need a method to slow the gear down, so that it turns at a measured rate. Or, we need something to consistently stop the escapement gear for a small amounts of time, then release it for small amounts of time. That cycle has to keep going. This is where the oscillations of the pendulum come into play.

 

 

We now take a rigid stick and attach a weight to one end (this weight is called a “bob”), and we”ll add a crossbar with two teeth to the other end (the crossbar is called a “pallet”). Imagine an elongated “T”, with the bob on the bottom and the pallet on the top. It’s like using a serif font: the two serifs on the cross of the “T” point downward, so do the teeth on the pallet. This “T” is our pendulum. As the bottom of the pendulum swings “right”, the left tooth of the pallet moves downward and meshes with the gears on the escapement, causing it and the weighted string to stop moving. Because of its oscillating characteristics, the pendulum will reach its full travel toward the right and will then begin moving back the other way. As it passes the bottom of its travel, the left pallet tooth now moves upward and releases the gear, allowing the escapement gear to “escape” (thus, the name “escapement gear”) and the weighted axle begins moving again. This time, as the pendulum passes center and continues its travel to the left, the right-side pallet tooth moves downward and it will now mesh with the escapement gear, causing the axle to stop movement, once again. The pendulum reaches its full travel to the left and once again begins moving toward the right. Thus, the axle with the weighted string is allowed to move, then stop, every time the pendulum makes full travel in each direction. They’ve done it! The weighted axle will not accelerate and use up all of its potential energy in a very short time, because it repeatedly stops moving. We have regulated the movement with the pendulum, and its movement is now predictable and can be transferred in a practical way.

 

The next post will explain what keeps the pendulum swinging, and not slowing to a stop.

 

Mantle clocks, wall clocks, grandfather clocks and cuckoo clocks often use a mechanical pendulum to regulate time. 

 

 

Ok, so Galileo discovered the pendulum. How does it work?

 

Most clocks were driven by weights and gravity. A string was tied to a rod, also called an axle, and a weight attached to the string. The string was wound around the axle. As gravity pulled on the weight, the attached string would be unraveled from the axle, causing the axle to turn, or spin. However, as gravity acts on objects, those objects begin to accelerate unless something interferes with, or acts upon that object. Until the pendulum, the weight on the clock mechanism just kept speeding up, and clocks would not keep accurate time.

 

Next post: how the pendulum and escapement are used to counteract gravity in weighted mantel clocks and table clocks.

 

“Some people don’t think much of clocks,” he said. “But there is a lot more to some clocks than one may realize. Really, they are pieces of art, history and mechanical marvel, what the people were able to do in those times, with no machinery.” Read the article at Clock collection marks history, craftsmanship

Take a look at the mantel clocks and wall clocks offered at MostlyMantelClocks.

Galileo was once bored as he sat through a church service. His mind wandered and noticed a chandelier’s repeated movement as it hung from the ceiling. He noticed that the chandelier swung from its center and stationary position, and no matter how far it swung, whether 5 inches or a foot, it still took the same amount of time (measured by his own pulse) to complete a full swing. That is, it took same number of heartbeats to complete its cycle from one extreme of the swing to the other. Thus, the pendulum was discovered to be an accurate tool in timekeeping, and paved the way for mantel clocks.

Before there were clocks, there was the Sun. Undeveloped cultures (both ancient and current) often allowed their lives to be regulated by the apparent movement of the sun. Life consisted of existing another day. The acts of survival included farming (though more like “gardening”), hunting, fishing, and maintaining shelter. Most of these actions required sunlight. Thus, when the sun rose, the people rose from sleep; when the sun set, the people soon set themselves down for sleep once again.

Sundials were used to mark off sections of the day, but many were designed to work in specific latitudes. Some were sophisticated enough to have a removable stylus so that the dial was portable and usable at other latitudes. One method of measuring time used candles. Graduations on candlesticks would slowly melt away as the burning flame continued its descent.

Of course, none of these methods measured time very accurately. One could only gather approximations of the passage time. Mechanical clocks began to be developed in the 1300s. These were “weighted” clocks, dependent upon gravity to pull weights connected to timing gears. However, accuracy was still a challenge because of the friction within the gear mechanisms. These clocks were difficult to regulate.

Spring-powered clocks were invented in the early 1500s. This enable smaller clocks to be built, even portable clocks, because the hanging weights were no longer necessary; however, regulation was still a problem because the as the springs unwound their force would dissipate. While clocks could now sit on a table, or the mantel of a fireplace, they still had only an hour hand.

It wasn’t until the pendulum clock appeared in the 1600s that clocks could accurately measure time to within one minute per 24-hours. In the 1700s, the errors were reduced to one second per 24-hours, and in the late 1800s to one-one hundredth of a second per 24-hours.

Mechanical clocks began taking many forms: Long-Case Clocks (also known as Grandfather Clocks), Mantel Clocks, Table Clocks, Wall Clocks, Bracket Clocks, et al. Many of these now fit the category of Antique Clocks, or Collectible Clocks. In future postings we will center on a particular style of clock.

MostlyMantelClocks.com offers a variety of mantel clocks, table clocks, and collectible clocks. Be sure to visit us and join our mailing list to receive periodic emails with special discount offers on selected items.