Basic general information in watchmaking(Complete).pdf

8/11/2019 Basic general information in watchmaking(Complete).pdf

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What is time?

Time is all the macro does not stop with the sustainability and irreversibility of the materialstate of the various process of change and continuous nature of the event common weights andmeasures in general.

Time is the description to the process of physical movement, is the artificial division between.

Time is the mentality processes for physical movement into segmentation, division .

Definition: The time is divided by people based on physical movement, not already there, theuniverse of "time" would not have been divided.

Physical movement takes time, but if you do not put time divided into partitions, our thinkingcan not identify. The reason we can think, because thinking of the physical world can be namedas real things, thinking is true, thinking named things with names, as used in thinking.

Without split-off "time", can not be named, can not be distinguished, only divided into "time", thethinking in order to be used, because the partition can be named after.

For instance, we put the Earth orbits the Sun once a year into the campaign process, the

movement of the Earth's rotation around the process is divided into day,Thinking of this division easy to calculate using the number sign. If you do not live on earth,definitely would not split the movement of the earth to time.

Therefore, t ime is a human invention to facilitate thinking, thinking about the universe, and todivide physical movement into time, is man-made rules, rather than what the natural rules. Is theartificial division between, whenever how to divide can be.


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Content s

Mechanical MovementSelf winding and manual winding watchAppearance and descriptionsDecorations

Functioning of a mechanical movementThe power sourceThe power reserve

The transmissionThe distributionThe regulationReviewThe RubiesThe anti-shock systemThe Lubrication

Simple and complication watchesChronograph and ChronometerWatch with calendar and other complication movements

Exterior of a watch
http://upload.wikimedia.org/wikipedia/commons/7/70/Wooden_hourglass_3.jpg


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Mechanical MovementSelf winding and manual winding watch

A mechanical watch is a watch that uses amechanical mechanism to measure the passage oftime. There are mainly two kind of watches, handwound watch and automatic watch. The internalmechanism of a watch, excluding the face andhands, is called the movement.

A mainspring which stores mechanical energy topower the watch. The spring loses energy as thewatch runs, the mainspring must be daily "wound"by the owner turning the crown on the case toprovide energy to run the watch, that is calledmanual winding movement.

An automatic or self-winding movement is, onecan wound the mainspring by turning the crown,also the mainspring can be wound automaticallyby the oscillating weight(rotor) on the movement,with natural motion of the wearer's arm to windthe mainspring of the movement, providingenergy run the watch, to make it unnecessary tomanually wind the movement.

Automatic movement with oscillating weight(rotor)

Mechanical Watch

(Automatic)Mechanical Watch

(Hand wound)

Manual windingmovement


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Mechanical MovementAppearance and descriptions

A thin metallic coating protects the component of the cage., generally plated with nickel, rhodium, gold,etc. This coating is first to insure a protection against the oxidation, and secondly to enhance theappearance of the components.

One generally designates a movement by the bridge side and the dial side.

A movement is composed of a cage that contains a certain number of components.

Cage is constituted of a basic piece called the main plate, on which are fixed the bridges. It is between the mainplate and the bridges that the gear train and other moving part are fixed.

Main plate is generally piece of brass and has certain number of recesses and holes. Some parts, pins and rubiesare pressed into the main plate

Bridges are elements of particular shapes, generally realized in the same material as that of the main plate. Theyalso have recesses, holes, post and rubies. Positioned and fixed in a precise way onto the main plate, that allowthe different components to stay in place.

Movement bridge side Movement dial side

Gears and escapement bridgeMain plate Barrel bridge


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Calibre

( ) ( ) caliber

calibre line : 1(line) = 2.255

line

Caliber ( )


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Mechanical MovementAppearance and descriptions

Dimensions

The thickness and the diameter of the cage give the dimensions of the movement that one calls a calibre .

The dimensions of a calibre are determined by its casing diameter(in mm) and its total height(in mm).

The diameter of the calibre is given in line: 1(line) = 2.255mm

The line is the twelfth of the inch, this last being the twelfth part of the foot. 1 12 inch

The Numbering

Every caliber carries a reference number(supposed) so that it

can be identified easily when ordering spare parts. This referencenumber is generally accompanied with the mark of themanufacturer. In addition, the number of rubies is engraved onthe main plate or on the oscillating weight.

Tapestry Cotes de Genve

Pearled Guilloch

The DecorationsThe decoration is the operation that consists of creating a pleasantvisual surface to look at. It is created on the component surface withthe help of small disks of emery papers or with abrasive millstones.Certain decors can thus be created such as cotes de Genve ,rounded or Guilloch patterns and tapestry.The bevels of the bridges are polished with diamond cutters. In somecases of very fine watch making, the peripheries of the bridges arestretched, beveled and polished by hand.


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1. 2. 3.

4.

1. 2. 3.

4.


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Functioning of a mechanical movement

1. 2. 3.

4.

1. The Energy Source2. The Transmission3. The Distribution

4. The Regulation


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The Energy SourceThe Barrel

If the user of a watch turns the crown to wind the mainspring, the user isthe energy source. One will be able to deduct that mainspring functions likean accumulator of energy.

Barrel

Mainspring

Barrel Cover

Mainspring

Barrel

Arbor

Hook on themainspring

The mainspringReturned S

The mainspring is an elastic metallic blade of rectangular section. The progress ofthe blade, rolled up against the barrel arbor and trying to take its initial shape,produces the energy necessary for the watch to work.The shape of the spring evolved from the spiral shape to shape of the returned S.Fully wound within the barrel. The spring is manufactured in order to assure apower reserve of approximately 40 hours.


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The Energy SourceMainspring inside a barrel

In a self-winding watch, the hook of the mainspring is replaced by a sliding bridle, that functionslike a safety valve.

When the mainspring will be fully wound, it will slip inside the barrel, preventing the mainspringfrom being over winding

Hook

Fully wounded UnwoundSelf-winding watch barrel

(Fully wounded)


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The Energy SourcePower Reserve Indicator

The power reserve of a watch is the time that elapse between the moment that the mainspring is fully wound andthe moment that the watch stops.

The term power reserve is used to designate the length of time the watch will work without the mainspring beingrewound. This corresponds to the available energy at any given moment.

The power reserve is shown on the dial of certain models, similar to the fuel gauge of a car.


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The TransmissionThe gear train

The energy accumulated in the barrel by the winding of the mainspring is going to allow the transmission ofenergy by means of the gear train.

The mainspring, while releasing itself, drags the barrel in rotation, then the gear train. The display of the hour bythe hands is also dependent on the gear train of the movement.

Barrel

Center wheel

Intermediate wheel

Seconds wheel

Escape wheel

Pivot

Teeth

A Wheel:This is a circular organ turningaround an axis. Its function is totransmit the energy to themovement.

Leaves


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-

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The DistributionThe Escapement

Escapement is a distributing organ to distributes the energy. The purpose of the escapement is tomaintain and count the oscillations of the sprung-balance of a watch.The escapement receives the energy provided initially from the gear train by the barrel andperiodically release a small amount of this energy in order to:- Maintain the oscillations of the regulating organ(sprung balance) to oscillate.-Cause the train to move in tiny increments.

To the sprung balance

Roller jewel(Ruby)

Roller table

Pallets

Pallet jewels(Rubies)

Escape wheel

Functioning withseconds wheel

Balance staff


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1.

2.

3. 4. 5. 6. 7. 8.

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The RegulationThe sprung-balance

The movement of the balance-sprung:

The balance- sprung oscillates around its neutral position, and this, in any position, contrary to a pendulum.

The balance-spring oscillates because if it is displaced from its neutral position, the hairspring is wound or unwound.This movement creates an energy that will bring the balance wheel back to its neutral position. As it has acquired acertain speed, it swings passed its neutral position, until the opposing energy of the hairspring stops it, and thenforces it to swing in the opposite direction.

1. Balance wheel

2. Hairspring3. Balance bridge4. Collet5. Stud6. Stud holder 7. Pins8. Regulator

The sprung balance system:The regulation organ of the mechanical watches is composed of a fly wheelcalled the balance wheel and a hairspring. The inner end of the hairspring isfixed onto the balance staff. The opposite end of the hairspring is fixed to theStud, which is fixed onto the balance bridge.


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1. 16 18

2.

Plain balance

Gyromaxbalance wheel

Balance wheel with screws

Cut bimetallic

balance wheel

Gyromax


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The regulationTypes of balance wheel

The Plain balance : The present balance wheels are build with two or three arms, theyare made of beryllium copper for the superior quality, in nickel for the standard quality.They have an excellent capacity of inertia in relation to their mass.

The balance wheel with c\screws:

In the past, the balance wheels were more complicated for two reasons.

1.To adjusting or easily modify the moment of inertia of the balance wheel 16 to 18 screwswhich are fixed on the balance rim. One could add or remove small washers between thehead of the screw and the rim, in order to increase or reduce the moment of inertia.

2. The former hairsprings were made of steel and dilated or contracted strongly accordingto the variation of the temperature. It changed the length and the strength of the hairspring.

For watches of high precision, it was necessary to find a system that counterbalanced thiseffect. One constructed the cut bimetallic balance wheel.

The rim is made of two metals(brass and steel). When the temperature changes, the twometals expand or contract at different rates, which distort the rim and modifies themoment of inertia.

The balance wheel is a fly wheel composed with a circular rim, held by arms.

Plain balance

Gyromaxbalance wheel

Balance wheel with screws

Cut bimetallic

balance wheel

The Gyromax balance wheel possesses a certain number of adjustable bolts thatallows to vary the moment of inertia by turning the slots of the bolts towards the insideor outside of the balance wheel .


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50 36 14 +10...

:18

Flat hairspring

Breguet hairspring


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The RegulationThe hairspring

The flat hairspring:

It is essential that a hairspring develops itself as concentrically as possible. It is becauseof the interior and outside attachments that this condition is difficult to satisfy.

For a flat hairspring whose outer end is fixed to the stud, the concentric developmentis not possible.

The hairspring is a metallic blade rolled up on itself in the shape of Archimede spiral. One requires a lot ofperformance from the hairspring. The couple must be as constant as possible whatever its elongation, thetemperature and the variation of the magnetic field.

The present hairspring is made with complex alloy: Iron 50%, nickel 36%, chromium 14% + 10% of tungsten,molybdenum, niobium, vanadium, manganese, silicon, titanium, aluminum, beryllium, carbon

The Breguet hairspring:At the end of 18 th century, the watchmaker Arnold and Breguet solved the problem.By giving a special shape to the last curve of the hairspring.

Flat hairspring

Breguet hairspring


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Review

So how the functions works together?Lets take a music box as an example. It posses a similar mechanism to a mechanical watch movement,their difference is, music box plays music, watch plays time.

Crown

Power source

Transmission

Distribution

Regulation

When a music box playing a song, the speed is steady controlled by the swinging of the governor (regulation).The governor controlling the speed of the pins roll (distribution) runs evenly to limit the turns of the gear train(transmission), in order to reduce the speed of the barrel spring (power source) runs out the energy whichstored. We then turn the crown (winding) to restore energy. Same as in a watch, the balance wheel swings tocontrol the escapement to distribute energy evenly from the mainspring inside the barrel through the geartrain, making time runs accurately on the watch. If the balance wheel and escapement removed, nothing tocontrol the barrel spring release, then mainspring will runs out within a second. And some people maymisunderstand that the balance wheel providing energy to the watch, but in fact, it takes the role to regulating.


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1704 Nicolas Fatio De Duillier

1902 August Verneuil

=

=

+ =


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The rubies

In 1704, this is the Swiss astronomer and optician Nicolas Fatio De Duillier, who discovered the way to drill the naturalrubies to use them as bearings in watches.In 1902, August Verneuil discovered a process in which to manufacture artificial fine stones.

Although made by man, the rubies represent exactly the same chemical, physical and crystallographic properties, so thatof the natural composition. In practice, the synthetic ruby presents decisive advantages to the natural one. It is indeedpurer and more homogenous. The synthetic surpasses the original, notably concerning its industrial applications.

The ruby and the sapphire are part of the same family.

CORUNDUM

The basis of the synthetic ruby is

ALUMINUM OXIDE

Without addition= white sapphire

Chromium oxide= red ruby Titanium + iron oxide= blue sapphire


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The rubies

The scale of hardness of the stones according to Mohs is found on the possibilitythat a stone has to scratch another one by rubbing.

Fluorite

Diamond

Quartz

Feldspar

Talc

Corundum


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( 0.055to0.10mm)

(C) (E)

a,b,c,d,e,


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The anti-shock system

To avoid that the pivots of the wheel(0.055to0.10mm of diameter) do not break at he time of a shock undergone

by the watch, some anti-shock systems have been created.Their principle consists in absorbing the shocks, by a part of the balance staff that is stronger than the pivots. Thisstronger part comes to stumble against the body of the device.

For that to happen, the jewels are fixed elastically into their place. In the absence of shock, the pivots of the balancewheel work normally. In case of shock, the jewel move, while allowing one part of the balance staff to absorb theshock. At the end the shock, all jewels take their original position.

a, Ruby bearingb, Springc, balance staff d, settinge, pivot


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1,

2,

3,

4,

5,

6,

7,

8,

:


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The lubrication

The lubrication is the fact to insert, between two pieces that rub one against the other, a product: the lubricant that

permits the decrease of the coefficient of rubbing and wear. It can be used under three forms: solid, liquid and gaseous.The lubricants used in watch making

What qualities should a lubricant have?

1, chemical stability

2, non corrosive properties for the components

3, non-creep stability

4, low temperature stability

5, low volatility

6, a stable and low coefficient of friction

7, prevention of wear

8, the insurance of a steady and high amplitude, whatever is humidity

What lubricants are available to the watchmaker?

The classic oils:

They are either vegetable (olive oil for example) or of animal origin (neat s foot oil). These oils have very goodlubricant properties and seemed to be the ideal lubricant for watch making.

Unfortunately, on contact with air and by the catalytic effect of the cuprous metals, they tend to oxidize and thereforeto have a short time efficiency. One tired to improve them by taking care of the refinement and mixing them withmineral oils. In spite of all the research, one will never get, even roughly, the stability that synthetic oils offer.


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1950 6 7 8

MOS2


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The lubrication

The synthetic oils:

They have been created, seen 1950, by the complex combination of chemical products. One distinguishes severalgroups of it. The first synthetic oils produced satisfied the first five requirements listed. On the other hand, no one hadbeen interested in the actual lubricant properties that are the subject of the requirements 6, 7 and 8. Studies to thistopic have been undertaken at the end of the seventies. These oils are constantly improved, the goal being to find thelubrication that rill have the longest life span.

The greases:

They are mixture of oils and fibrous soap that acts as sponge to keep oil. There is also a grease for watch makingconstituted of oil and powder of molybdenum disulfide(MoS2) used like binder.

The greases are of a delicate use. They must be perfectly homogeneous before it can be used and should acts like alubricant. For the escapement, the grease must not produce any micro-droplets under the effect of the shocks whenmechanical contact is initiated.

Self- lubricating material and coatings:

Numerous studies are still being led, without any revolutionary solution discovered so far.

The choice of lubricant:

Considering the complexity of the problems to solve, the watchmaker is obliged to have a full confidence in the

recommendations of the watch making lubrications, and the technical brochures provided by the watch makingmanufactures, indicating with precision the products of cleanings to use, the advisable lubricants, the quantities and theplace where to put them.

It is essential to deposit a lubricant onto a perfectly clean surface.

It serves no purpose to apply a drop of oil on a dirty component or to one that has already been oiled, as the oil willnot remain in place.


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C.O.S.C(Contrle Officiel Suisse des Chronometres )

9 -4 +69 -5 +8


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Simple and complication watchesChronometer and Chronograph

A chronometer means watch of high precision, whichindicates the second, whose movement has beentested during 15 days in different positions anddifferent temperatures, by a neutral official organism"the C.O.S.C" (Official Swiss Center ofChronometers). The movement that are in the criteriaof precision.

Movement bigger than9''' -4 to +6 seconds per dayMovement smaller than 9''' -5 to +8 seconds a day

receive an OFFICIAL CERTIFICATE of CHRONOMETER


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A chronograph is an instrument(watch) with which one can read the time and measure a lapse of time, on

demand, with the help of a chronograph mechanism.

Watch with chronograph


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( Zegna 20th anniversary watch ).


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The chronograph is a separate mechanism added to the movement of a watch. It is used to measure laps of

time in sport events, industrial operations, laboratory experiments or all other application that requiresknowing a precise lapse of time.

(Refer to our Zegna 20th anniversary watch ).

Watch with split-seconds chronograph


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(28, 29, 30 31)

312 28 4 30


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Simple and complication watchesWatch with simple calendar

The simple calendar watch indicates the day, the date, the month and the phase of the moon, but it does not make intoaccount the variation of the days in the month (month of 28, 29, 30 or 31 days).

In other words, the user of a watch with a simple calendar mechanism should do a manual intervention at the end of eachmonth that count less than 31 days. For example, February 28 or April 30, it will be necessary to do a manual intervention.

Day

Phase of the moon

Month

Date


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29 12 44 2.8 29.53 59 29.544 2.8 9

3 1


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Simple and complication watchesIndication of the phase of the moon

A disc on which the moon is represented two times indicates the phase of the moon. A suitable shape apertureinto the dial permits to see a part of the disc, revealing a waxing moon, a full moon or a new moon.

The length of a lunar cycle is 29 days, 12 hours, 44 minutes and 2.8 seconds (29.53 days). The length if a lunarcycle with a star wheel of 59 teeth is 29.5 days. This mistake that results from this difference is 44 minutes and2.8 seconds per month, either close to 9 hours per year.It means that after 3 years, there will be a error of 1 day in the given indication. Then a manual correction shouldbe undertaken.


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28 29 30

(7 ) (48 )

(31 )(59 )


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Simple and complication watchesThe perpetual Calendar

A perpetual calendar permits like a simple calendar mechanism, to indicate the day, the month and the phase of themoon, and ALSO takes automatically into account the length of the months (28, 29 and 30 days), even the leap years,and these without manual intervention.

Leap year counter Day star

(7 teeth)

Month star (48 teeth)

Date star (31 teeth)

Moon phase star (59 teeth)


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Simple and complication watchesThe perpetual calendar with complete year

Year system


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,08:11

= GMT+8 = 16:11=GMT-5= 03:10

10:11 = GMT+2


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Simple and complication watchesGMT Indication

Greenwich Mean time at the meridian of the Royal Observatory in Greenwich, England, which is the prime meridian of the world.GMT is a civil time beginning at midnight .

With the help of the GMT indicator, one can notice every country s actual time accordingly with their time zones from the tim ezone map.

.

GMT time zone map

According to this watch, if the GMT now is 08:11ThenChina= GMT+8 = 16:11East coast of USA=GMT-5= 03:10The time now 10:11 = GMT+2Which means showing the time of East Europe, and Egypt, etc.

GMT hand


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Simple and complication watchesThe two time zones watch

The second time zone


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Simple and complication watchesThe three time zones watch

Secondtime zone

Thirdtime zone


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In an alarm watch, which may be used as a memory aid, the mechanism which releases the alarm is identical to that in analarm clock.One part of the movement is conventional, with its own stem (time setting and winding), and the other part of themovement is the alarm with its own stem as well (alarm time setting and winding).

Simple and complication watchesThe alarm watch

Alarm indication

Crown of the alarmmechanism(alarm

time setting & Winding)


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(15 ) 02:17


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Simple and complication watchesThe minute repeater

A minute repeater watch

Slide

The minute repeater mechanism indicates on demand, the time to the nearest minute bythe sound of two hammers hitting two gongs of different pitches. The low pitch dong standfor hours, high and low pitches ding dong stand for quarters, high pitch ding stand for minutes.For example, if the time now is 02:17, then when we slide, you will here the sound dong, dong,

ding dong, ding, ding .

Minutehammer

Hour hammer


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2, ( )

3,


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The grande sonnerie' strikes the hours and the quarters automatically, like a grand father clock. And ithas the same characteristics as the minute repeater. It strikes the hours, quarters and minutes ondemand.

By moving a push piece the grande sonnerie has 3 functions:

1, Grande sonnerie

2, Petite sonnerie (minute repeater only)

3, Silent

Simple and complication watchesThe grande sonnerie


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A. L. Breguet, 1801 .


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The tourbillon

A. L. Breguet, created the tourbillon system in1801. The purpose of this device is made to improve theaccuracy of the watch. The carriage is fixed on the second's wheel axis, makes one complete turn everyminute, to average the errors of rate in the vertical positions.

Simple and complication watchesThe rotating regulation system

A tourbillonmovement

Tourbillon escapementcarriage


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The carrouselOne can see that the sprung-balance is not on the center of the carriage. This is the main difference betweena tourbillon and a carrousel. The carriage is usually placed on the arbor of the intermediate wheel so that thecarrousel carriage makes some of them a complete turn every one minute or 4 to 6 minutes.

Simple and complication watchesThe carrousel


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24


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Simple and complication watchesThe retrograde systems

The retrograde systems

A retrograde system is a system provided with a hand (of hours, minutes, seconds, calendar etc.) whichmoves on an arc of circle, drawn on an dial, and not on a complete circle.

Which means that when the hand reaches the end of the arc of circle, it comes back instantaneously to itsstarting point.

Retrograde 24hour

counter Retrograde daycounter

Retrograde datecounter

Retrograde secondscounter


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60


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Simple and complication watches Jumping system

Watch with the hour indication appearing in an aperture made into the dial. When the minute hand arrives on 60,

the hour jumps instantaneously to the next numeral.

So this is a watch with minute repeater, small seconds and jumping hours

Hour indication


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Exterior of a watch

The exterior of a watch comprises all the components added to the movement which contribute to:

Its final appearanceThe protection of the movement

The way it is fixed in place and how it is used

These components are the glass, the dial, the hands, the case, the gaskets, the crown and its tube, the push-piece and thebracelet.

Glass

Mid-case

Crown

Dial Hands

Movement

GasketCase back cover

Crown tube

Movement ringCase back glass


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:

:

PVD

keramos


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Material used to make watch case

The materials used to make watch cases must fulfill the following conditions:

It must be rust proof.It must not be affected by contact with sweat and normal environmental conditions.

It must be hard-wearing.

In the luxury watch industry the cases of the watches are generally made out of stainless steel, titanium, silver, goldof various color and platinum.

But nowadays, the creators use a lot of different materials like synthetic matters, ceramics, wood, etc

The stainless steel :

The stainless steel is the ideal material to make watch cases. Its toughness and its resistance permit to achieve aresistant and everlasting product. In the other hand it is difficult and expensive to manufacture.

The brass:

Brass is easy to manufacture, and it is suitable to be covered by galvanic treatment. The watch cases made out ofbrass are inexpensive, but their life span is limited. As soon as the protective layer wears off, by rubbing or abrasion,the brass will corroded very quickly.

The titanium:

It is a blackish metal. Its oxide is a coloring agent for the sapphire. The nitrate of titanium is used in the P.V.D coatingof the watch cases.

The ceramics:

In Greek, the word "keramos" means clay (potter's earth). Since this very old origin, the ceramics have undergone,and still undergo, a considerable evolution. They are a complex composition of inorganic, minerals, metallic andcrystalline substance.


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1, ;

2,

3, 1995 8 1


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E t i f t h


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Exterior of a watchTypes of hallmarks

St. Bernard hallmark


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Exterior of a watch


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Exterior of a watchThe standard (purity)marks

Gold

18 carats yellow: pure yellow gold 750%, silver 125%, copper 125%

18 carats pink gold: pure yellow gold 750%, silver 45%, copper205%

18 carats white gold: pure yellow gold 750%, palladium125%, copper 95%, silver 30%

Silver

Sterling silver: pure silver 925%, copper 75%

Platinum

Platinum: pure platinum 950%, palladium, cobalt, copper 5%


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Exterior of a watch


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Exterior of a watchMaker s marks


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f


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Exterior of a watchThe casing ring

The casing ring

The casing ring is a ring, which is fitted around the movement when it is placed into the case. It can bemade of steel, brass or synthetic material.

It is used to fill the space that is between the watch case and the movement. It allows to fit a movement ofa different shape of the case.


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Exterior of a watch


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Exterior of a watchThe crowns

The crown

The winding crown is screwed onto the winding stem. The winding stem fits into a hole in the side of thecase. If this hole were not sealed, humidity, dust and fine fibers from clothes will get into the movement.

Watch case

Joint

Crown tube

Crown with Winding stem


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,

Exterior of a watch


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Exterior of a watchThe gaskets

The gaskets

Gaskets ensure a water-resistant seal between two parts, the winding crown and the crown tube, for example, orbetween two fixed parts, such as the back and the case.

In principle, a gasket must always be elastic and should never be compressed if it is to fulfill its function.

In this case it should be lubricated to allow it to slide. Back cover gaskets are often designed to be compressed to amaximum. In this case, it is preferable to change them each time the watch is opened, since they may have beendistorted.

A gasket


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1.

2.

(). (loctite ).


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Exterior of a watchThe cements

Cement is used for two purposes in watch making:1. To fix a part: e.g. the winding crown to the winding stem

2. To create a seal: e.g. between the glass and the bezel

Cement is in fact often used for both purposes at the same time. The type of cement used is frequently anaerobic(it solidifies in the absence of air). This explains why jars of such cement are always only half full (loctite).


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.

100


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Exterior of a watch


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The dials

Dials are generally flat brass discs, beveled or domed, which are fixed onto the dial side of the movement

by dial feet.


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18

1875 Nemitz

Exterior of a watch


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Exterior of a watchThe hands

The hands

The hands of a watch are not simply indicators. Like the other exterior parts, the shape and appearance of thehands help to give a watch certain style.

Hands are made of brass, steel, gold, aluminum or special alloys and may be galvanized or painted, oxidized. 18carats hands are left untreated.

In 1875 Nemitz invents phosphorescent sulfur-calcium as the first luminous material for hands.


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60

Exterior of a watch


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The leather straps

A single strap must go through more than 60 different stages, from preparing the skin to the final finishing touches.

The manufacturing process is therefore organized as a series of specialized workshops, such like choose the skin,cutting the straps, splitting and paring, padding, stitching, finishing and several final stages. Which means it takes aconsiderable amount of time to produce just one strap.

Cow leather Ostrich skinSupple yet solid, ostrich skin is

irregularly patterned with quillmarks which mark the positionof the biggest feathers. Shark skin

Unique for its pattern. Generallyspeaking, the ridges are died oneshade lighter than the color of the skin, or blackened.


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Exterior of a watch


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The leather straps

Caiman skinCaiman skin has more or lessround scales, which are lessrectangular than those of thealligator

Alligator skinThe alligator can be distinguishedfrom other crocodilians by theSquare or rectangular scales onIts belly and the round scale onIts flanks.

Lizard skinIts akin is resistant, and can berecognized by the very small, roundScale at the center, which become

Basic general information in watchmaking(Complete).pdf

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