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FAQ: Frequently asked questions

All watches are made by Aeromatic 1912 - Frankfurt/Germany
Limited Edition


How long is the usual delivery time?
Delivery time

The normal delivery time is 10 to 14 days, but it can rise up under certain circumstances not caused by us to 4 or 5 weeks.


Where are our watches manufactured?
Our watches

All our Aeromatic 1912, Tauchmeister 1937 and Haffstreuner watches are made by a small company here in Germany with which we work closely together. The movements we use are german, swiss or asian ones.
Most movements are made by Ronda or ETA in Switzerland or Miyota and Japan CBM Corporation, manufactured by CITIZEN WATCH CO. (LTD), in Japan.


Do you have instruction manuals?
Instruction manuals

Currently we have no printed manual. But we can assist you on all functions of our watches. Please feel free to ask any question you have.
Some manuals from Ronda, ETA, Miyota and Japan CBM Corporation are available for download. Here is a list of movements, where you can download a manual:


Do we also ship to your destination?
We ship worldwide

We sell our watches worldwide, within Europe plus 19% VAT!

Countries, where we don't deliver are

What are your shipping costs?
Payment within Europe
Payment outside Europe
Shipping

Do we have a complete list of all our watches?
All our watches

For a complete list of all our watches please visit our accompanying website at www.watches-for-sale.de.


What are complications?
Complications

All watches tell the time, of course. Some do more than that, like chime out the hours and minutes, show when the next leap year will be or time a series of runners as they cross the finish line of a race.
In mechanical watches, these extra functions are called complications. Traditionally, that word is seldom used if the watch is quartz. In that case, a function is usually referred to simply as, well, a function. Quartz watches with several different functions are often called multi-function watches.
 
© awci.com.


What is a tachymeter?
What a tachymeter does

The tachymetre scale can be used to compute many things, but it's primary purpose is to compute the speed after noting how long it takes to travel a fixed distance (e.g. one mile or kilometer). The dial is a logarithmic scale which computes the function:
Tachymetre Dial = 3600 / Elapsed Time in Seconds
The scale is valid for all elapsed times from 7.2 seconds to 60 seconds. If the duration of the event is outside this range, then the answer on the dial is invalid.

How to use a tachymeter

For example, suppose you wanted to measure the average speed a racecar was traveling. After starting the chronograph function when the car passes the starting line, and stopping it after the car travels exactly one mile, you note that the chronograph hand is pointing at the 4 o'clock position (i.e. 20 seconds have elapsed) Looking beyond the 4 to the Tachymetre dial reveals the chronograph hand pointing at 180. This means that the average speed of the car would be 180 MPH.
Let's say, instead of the race car speed, you are measuring something much slower, like sailboat speed. In this case, you need to use a shorter distance because the elapsed time must fall within the 7.2 - 60 seconds range. For this example, let's say it took 36 seconds for your sailboat to travel 1/10 of a nautical mile. Reading the tachymetre dial gives a speed of 100 knots. However, since we only traveled 1/10 of a nautical mile, the actual answer is 1/10 of that or 10 knots.
Now let's say you wanted to measure the speed of a VERY, VERY fast airplane: after traveling 10 kilometers, you noted that 10 seconds have elapsed. The tachymetre dial gives an answer of 360 but we traveled 10 Km. Therefore, the answer is 10X360, or 3600 km/hour.
There is really nothing magic about using the Tachymetre dial to measure speed. You can also use it to measure other things, like gas consumption. Suppose it took 50 seconds to burn up a gallon of gasoline. Reading the tachymetre scale shows that you are burning 72 gallons of gasoline per hour.
 
© www.righttime.com.


What are jewels?
Jewels

Most people think of jewels as being something that are valuable because they are so pretty, but their use in watches was, I believe, the first time that jewels were used for their functional value. (Well, possibly diamond dust on drill bits was first, I'm not 100% certain.)
The jewels used in watches are usually rubies, sapphires (which are chemically the same as rubies), garnets and diamonds. After around 1900, most of the rubies used were synthetic. Before 1900, the jewels were either from stones that were too small or had too many flaws to be used in jewelry. In either case, they really weren't that costly. There is often a correlation between the price of the watch and number of jewels, but the jewels themselves are not the cause of this higher price.
Reducing friction is an extremely important goal in watchmaking. Jewels have two important properties that help reduce friction. First, they can be made to be very smooth, and therefore they let the metal parts slide easily. Secondly, they are very hard and therefore don't wear down very quickly. The gears in a watch are carefully designed so that the teeth roll on each other, rather than sliding. If the axle of a gear wears away the hole that it sit in, the gear will shift. That means the teeth will no longer roll on each other and therefore friction will be increased.

Types of Jewels

There are several different types of jewels used in a watch, the most common are:

The jewels are carefully shaped so that the capillary action of the oil causes the oil to be drawn toward the gear arbors instead of spreading out where it doesn't do any good.


Hole Jewel

Hole and Cap Jewel


Pallet Stone Jewels

Roller Jewel

Locations of the Jewels

The jewels are located throughout the watch at key spots. The following are typical locations for the jewels, as shown on the following diagram:

  1. The basic 7 jewels are part of the escapement and balance. They include cap and hole jewels for both the top and the bottom of the balance wheel (total of 4), the two pallet jewels and the roller jewel
  2. The next 8, making 15 jewels, are hole jewels for the fast moving part of the gear train
  3. The next 2, making 17 jewels, are jewels on the center wheel
  4. The next 2-4, making 19-21 jewels, are cap jewels on the escape wheel and the pallet fork

Some watches, mostly pocket watches, the mainspring barrel will be jeweled. In order to safely jewel the mainspring barrel, the watch needs to have a "motor barrel" instead of the more common "going barrel". This can bring the jewel count up to 23 jewels, which is the maximum you will normally see on a pocket watch.
Additional jewels are often needed to make automatically wound watches efficiently transfer the small amount of power generated by moving your wrist into the power needed to wind your watch. More jewels are often used for chronograph functions, time repeater chimes, and date/date displays. Very complicated watches can have over 40 functional jewels.

Shock Protection Jewels

In a shock resistant watch the jewels that carry the heavy balance staff are mounted in springs. The springs take up shock and help prevent breakage of the either the jewels or the tiny balance staff tips. If the shock is large enough, the thicker parts of the balance staff will knock up against the plate that the jewels are mounted on. While this will cause the watch to stop ticking for a split second, it also prevent any damage, even in extreme cases.
The kind of shock protection pictured here is called "Incabloc" and was invented in the mid 1930's. The first form of shock protection was invented by Breguet in the late 1700s.


Jewel mounted on spring

Jewel on Balance


Normal position of balance staff

Shock, down and sideways taken up by spring

The Relationship between Jewels and Quality

As mentioned above, the jewels themselves are not that expensive, but watches with more jewels tend to be the higher grade and more expensive. The general public, over the years, have associated lots of jewels with high quality and some manufactures have taken advantage of this false connection to fool people by adding non-functional jewels.
On a 7 jewel watch, the only jewel that can easily be seen is the cap jewel on the top of the balance staff. When additional jewels are added, you normally can only see half of them as the other half of the jewels are hidden under the watch dial. Some watch companies would jewel only the end of the wheel arbors that was visible, thus making the watch appear to be higher grade than it really was.
Most of the additional labor needed to create a high grade watch is from making sure that the watch has the consistency needed to adjust the watch to high tolerances. Additional jewels can make it easier to get this consistency.
One of the downsides of jewels is that they break much easier than metal bushings. Most watches made before the mid 1890s had a maximum of 15 jewels, even the highest grade railroad watches. "Over Jeweling" a watch was thought to make the watch less rugged so it was considered, especially by the Swiss, that jeweling the center wheel to bring the watch up from 15 jewels to 17 jewels was not necessary. The center wheel does not need to be jeweled to reduce friction because it moves so slowly. Since the center wheel arbor sticks through to the dial side of the watch and drives the gears that moves the hands, the bottom jewel is especially easily broken.
A highly jeweled watch will usually not wear out as quickly as a watch that doesn't use jewels but, again, jewels are not required to make a very accurate and high grade watch.
Jewels are added to make it easier to create a high grade watch, but adding jewels alone will not make a watch high grade and many high grade watches do not have lots of jewels.
 
© Elgin Watches (modified by Aeromatic 1912).


 
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