Handbook of Watch and Clock Repairs (1972)

OVERHAULING AND CLEANING

shake. With a pair of tweezers hold the hour hand by its socket

and lift the hour wheel up and down. If there is no end-shake

remove the minute hand and try again. If end-shake is now

present it indicates that the hour hand or the hour wheel pipe is

fouling the minute hand and that it is necessary to lower the hour

hand on the hour wheel or reduce the length of the hour wheel

pipe.

If, however, removal of the minute hand makes no difference

look to see if the hour wheel pipe is fouling the dial hole or if the

hour wheel is binding on the cannon pinion.

The latter two faults will also eliminate side-shake which is the

next check to make. Additionally, if the depth of mesh between

the hour wheel and the minute wheel pinion is excessive the side-

shake will be reduced or eliminated altogether. It is essential that

the hour hand has complete freedom of movement in both

directions otherwise the resistance offered up will have a retarding

effect on the time-keeping of the watch if not stopping it com

pletely.

Remove the minute hand and the hour hand with the levers

illustrated in figure

10, and at the same time take precautions

against damaging the dial by placing beneath each lever a piece

of folded tissue paper. Hold the levers, one each side of the hand

to be removed, and by applying light equal pressure downwards

the hand will come away. The seconds hand is removed by the

action of lifting off the dial.

The movement may now be taken from its case. There are a

number of methods used to secure movements so let us consider

those that we are most likely to meet.

The movement of a keyless watch fitted to a two-piece case,

such as is illustrated in figure 69, is made to slide into the case and

is held in position by the bezel. To remove it pull out the winder

into the set-hand position and by holding the winder gently ease

the movement from the case. The use of a small screwdriver as a

lever will assist this operation if the movement sticks and fails

to lift out squarely.

The keyless watch with the three-piece case is rather different.

WATCH AND CLOCK REPAIRS

The movement, less the winding stem, is put into the case middle

from the front and is prevented from passing right through by the

aperture of the case middle being smaller at the back.

The movement is held in position by dog screws, usually two

in number. These screws have large diameter heads and are

inserted at the back of the movement. In screwing them into the

watch plate the heads tighten on to a lip of the case middle and

hold the movement secure.

Some dog screws have almost half of their heads cut away.

These screws only have to be turned slightly to bring the flats of

their heads in line with the case lip and the movement is freed

without the necessity of removing the dog screws.

With these watches the winding stem passes through the case

middle before entering the movement and is therefore inserted

after the movement is in position.

To take the movement out, slacken the pull-out piece setting

bolt, withdraw the winding stem, slacken or remove the dog screws

and carefully push the movement forward and out.

Some of the earlier key-wound watches have their movements

hinged to the case middle with a spring catch diametrically

opposite to hold it. To take the movement out necessitates the

removal of the hinge pin.

Whatever the method used, however, careful examination will

indicate the procedure for dismantling.

Having taken out the movement we now have to lift off the

dial. In the majority of watches the backs of the dials have two

copper feet soldered diametrically opposite each other. These

feet pass into holes in the bottom plate and are secured by

screws entering the bottom plate from the side. Slackening of

these screws frees the dial. Usually a little assistance is required

because the screw tension causes slight bending of the feet

preventing them from being lifted straight out. Insert a thin blade

of a pocket knife under the dial close to the feet and slightly twist

the blade so that the pressure on the dial takes place at the base

of the feet. This method will prevent the dial from bending, a

precaution which is essential with enamel dials in particular to

OVERHAULING AND CLEANING

prevent cracking of the enamel. When lifting the dial off take care

not to lose the seconds hand if there is one fitted.

Another method used to secure the dial is the fitting of dog

screws.

These screws have a conical flange half way down their length.

One side of the flange is cut away. The screw is inserted in the

plate parallel and adjacent to the dial feet and turned so that the

edge of the flange passes into a slot cut in each dial foot. By

rotating the screws half a turn inward the cut away portion faces

the dial feet and enables the dial to be withdrawn.

The dials of some of the cheaper watches are made with small

tongues on the edge that are bent over to grip the movement when

the dial is in position. When these tongues have been bent a few

times they snap off and means of securing the dial are lost.

In handling a dial of this kind it is essential that the tongues are

bent as little as possible.

Having removed the dial inspect the underside for signs of

fouling. The dial may have been pressing on the minute wheel

pinion. If this happens the timekeeping will be erratic. The

minute wheel pinion may bind only in certain positions. When the

watch is not being worn the pressure of the dial on the pinion

may just be sufficient to stop the movement, but the action of

disturbing the watch may cause the movement to function again.

During the time the watch is worn the effect may be a slowing

down at intermittent periods.

Should there be some doubt as to whether fouling is taking

place, a drop of oil on the pinion can be used as an indicator.

Replace the dial, operate the hand-set and rotate the motion

work. Remove the dial and inspect again. Any trace of oil on the

underside is an indication that there is insufficient clearance

between the dial and the minute wheel pinion.

There are two methods of increasing this clearance; by remov

ing metal from the underside of the dial or by reducing the height

of the minute wheel pinion.

In the case of a metal dial take a chamois leather and fold it

into four thicknesses and place it on a flat block of wood on the

WATCH AND CLOCK REPAIRS

bench. Over the chamois leather place two thicknesses of tissue

paper, then lay the dial face downward on it.

Scraping is done with the tip of a very sharp knife. The strokes

must be as light as possible to prevent bruising of the dial face.

Continue scraping until all the pinion marks have been removed

and then fit the dial to the movement and test again by the oil

method.

To reduce the thickness of an enamel dial a carborundum stick

is required. These are made specially for the job and can be

obtained from your supplier.

Support the dial as for a metal dial. Moisten the carborundum

stick in water and rub it fairly heavily over the affected area in a

circular motion. Continue this grinding action until all traces of

fouling have been removed or until the copper dial shows through.

If the copper does show before the pinion marks have been

removed then it is advisable to stop work on the dial and have

the height of the minute wheel pinion reduced in a lathe.

Earlier in the chapter it was mentioned that before removing

the hands, a little side pressure should be given to them to find

out if they were tight on the wheels. In the case of the minute

hand although the hand may have been tight on the cannon

pinion, nevertheless the cannon pinion may have been loose on

the centre arbor.

This is a very common fault with the snap-on type of cannon

pinion and is a constant source of trouble.

The centre arbor is machined with a groove all round it. The

cannon pinion is similarly machined and the base of the groove

is then burnished inward causing an internal bulge. It is this

bulge that locates the pinion on the arbor and provides the

friction drive.

The remedy against slipping is to reburnish the cannon pinion

groove until it grips the arbor once again.

Lift off the minute wheel and check the tightness of the minute

wheel post. Then hold the minute wheel between finger and thumb

and grip the minute wheel pinion by inserting the points of the

tweezers between the leaves. Rock the tweezers to find out if the

OVERHAULING AND CLEANING

minute wheel is loose on the pinion. Replace the minute wheel

on its post.

Depthing of the wheel teeth must now be tried. First remove

the hour wheel and try the depthing between the cannon pinion

and the minute wheel. Then replace the hour wheel and try the

depthing between the hour wheel and the minute wheel pinion.

After carrying out these checks the wheels must be rotated so that

depthing can be tried with a different set of teeth. Repeat this

until each wheel and pinion has been tried in four different

positions.

On the bench in front of you place a sheet of stiff white paper

on which the parts can be placed as they are removed from the

movement. The parts should be kept together in groups complete

with any screws. Sometimes the screws in one group are similar

but one is slightly longer than the others. It is important that a

screw is not used where a shorter one should be. There is the

possibility of the end of the thread fouling something which may

prevent the screw from being tightened or may cause the watch

not to function.

The screws should, therefore, be placed in or near to their

respective holes in the part to which they belong.

Now turn the movement over in readiness to remove the

balance.

With the mainspring partly wound carry out an inspection of

the escapement and make notes of any faults. Details of this

inspection are contained in Chapter

10.

If the watch is fitted with a cylinder escapement the mainspring

must be let down before the balance is removed, otherwise the

train of wheels will be driven by the mainspring at high speed

which will invariably lead to damage of the pivots.

To let the mainspring down hold the winding button, or the

key in the case of a key-wound watch, and make a slight turn in

the direction of winding. This will partly raise the click which can

then be fully released from the ratchet wheel by the point of a

pegwood stick.

The tension of the mainspring is now directly transmitted to

WATCH AND CLOCK REPAIRS

the winding button which, if allowed to rotate slowly between the

finger and thumb, will permit the mainspring to unwind.

Care must be taken not to let go of the button whilst the click

is held back because the mainspring will then unwind itself at

high speed and cause damage to its centre. If it is felt that finger

control of the button is being lost, release the click into the

ratchet wheel and try again.

When the movement is in this position it must not be laid on the

bench and worked on because the centre arbor that carries the

cannon pinion and the fourth wheel pivot that carries the seconds

hand will be projecting.

Either the movement rests at an angle on the bench and is

supported in the hand, or a watch movement stand must be used.

Adjustable stands can be purchased but a length of metal tube

about

1 1/2 in. long, squared at the ends and of suitable diameter

will do quite well.

Take out the screw holding the balance cock and very carefully

lever the balance cock up. A small notch will be seen on the edge

of the cock into which the blade of a small screwdriver can be

inserted. Because the leverage will be concentrated at one end

there will be a tendency for the cock to press down on the

balance pivot at the other end. This must be prevented and once

the balance cock has been moved it must be brought level again

by raising the other end in tweezers.

Once the balance cock pins have been withdrawn from the

bottom plate the cock can be lifted from the movement with the

balance wheel and spring hanging from it.

You may find there is a tendency for the balance wheel to

catch and not come away. This will be because the roller is

caught in the lever fork. If this happens any further attempt to

lift the balance will only result in the coils of the hairspring being

pulled out.

To free the roller, the cock is held stationary above the move

ment, and the movement is slowly turned until the roller is

freed.

Lower the balance to the bench and when the bottom pivot

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touches the paper roll the cock over on its back. In doing this the

spring will cause the balance wheel to do the same. The balance

wheel is now held in the tweezers and positioned so that the

balance pivot rests in the jewel hole in the regulator index.

The balance now has to be separated from the cock. First,

examine the index pins. Some watches are fitted with one fixed

pin and one movable pin. The movable pin has a lip on the top

that bridges the gap between the two pins and so prevents the

outer coil of the hairspring from coming out. This movable pin

has a screwdriver slot in the end enabling the pin to be turned

thus swinging the lip clear and making it possible for the hair

spring to be removed.

Now remove the stud from the balance cock. Studs are either

held in by a screw or they are a push fit. If the stud is the latter

type, grip it firmly with a pair of strong tweezers and gently ease

the stud out, taking care not to alter the bend or set of the hair

spring.

Lift the balance clear and place it on the white paper along with

the balance cock screw.

It is advisable at this stage to leave the index assembled to the

cock and remove it only when you are ready to clean it.

If the movement is not fitted with a cylinder escapement then

you will not have unwound the mainspring.

The pallets are next to be removed and so we must let the

mainspring down.

Having done this, remove the screws from the pallet cock, lift

the pallet cock away and remove the pallets.

If the wheel train starts to rotate, it is only because by releasing

the click from the ratchet wheel it is not possible to completely

let down the mainspring. However, what little energy remains in

the spring quickly spends itself with no damage to any part.

Before removing the wheels, turn the watch over so that the

cannon pinion can be removed. Because the cannon pinion is a

friction tight fit on the centre arbor all that is required to remove

it is a straight pull. Care must be taken, however, in avoiding

damage to the pinion when it is being held. One of the safest and

WATCH AND CLOCK REPAIRS

most simple methods is to grip the cannon pinion in a pair of

brass-faced pliers.

With the cannon pinion removed turn the movement over

again.

Before proceeding with the dismantling of the wheel train we

must test the depthing. Take a pegwood stick and shave it to a

blunt point. Press the end of the stick on to the fourth wheel pivot

and hold the wheel. With another pointed pegwood stick touch

the third wheel and try the shake of the third wheel teeth in the

fourth wheel pinion. Repeat this process for the other wheels.

In Plate IV it will be seen that the escape wheel, fourth wheel,

third wheel and the centre wheel are all held in position by a train

wheel bridge. This arrangement does not apply to all watches.

In some movements the centre wheel is held in by a top plate and

the remaining wheels are supported in the same cock or bar. Then

there is the bar movement in which each wheel has its own bar.

This method is preferred by many watch repairers but the other

methods have obvious advantages.

Remove the screws from the wheel train bridge and carefully

lift the bridge off. Some bridges will have small notches similar

to that previously mentioned in the balance cock for the insertion

of a lever. The bridge or cock has locating pins underneath and

as soon as they are free of the bottom plate the bridge will come

away. Lift out the wheels and place them with the bridge and the

screws.

Now remove the click, click spring, transmission wheel and

ratchet wheel from the barrel bridge. Some watches are fitted

with transmission wheel screws with a left-hand thread and this

must be borne in mind when attempting to loosen the screw. It

is as well to get into the habit of trying to turn the screw first one

way and then the other slowly increasing the pressure until the

screw eventually turns.

Remove the barrel bridge and lift out the mainspring barrel.

This leaves the bottom plate with the balance endpiece and the

keyless work.

Lift the crown wheel and the castle wheel from the plate.

OVERHAULING AND CLEANING

Remove the pull-out piece check-spring, the pull-out piece screw

and the pull-out piece itself. Lastly remove the winding stem.

Remove the balance endpiece screw and allow the endpiece to

drop out. If the oil keeps the endpiece in position take a pointed

pegwood stick and turn the endpiece. Now with the same stick

the endpiece can be pushed out from the other side of the bottom

plate by inserting the stick in the endpiece screw hole.

The dismantling of the watch is now complete with the excep

tion of the balance cock index and the mainspring barrel.

It is the intention t h a t these t wo assemblies r e ma i n as they ar e

until we are ready to clean them.

O n the b e n c h i n front of us we n o w have all t h e p a r t s on t h e

sheet of white paper. The parts have been placed together in their

groups and we have made quite sure that the screws have been

placed in or alongside their screw 'holes.

This grouping of the parts will considerably ease the task of

assembly as you will see when you first tackle the job.

We are n o w ready to start the cleaning and so we will c o m m e n c e

b y getting together o u r e q u i p m e n t a n d materials.

The parts are washed in a cleaning fluid (see Chapter 2). A small

clean pan will be required for use as a washing bath. A pan

measuring 3 in. x 2 in. χ 3/4 in. will be sufficient.

Two watchmaker's brushes will be required, one with medium

bristles and the other with soft bristles, and a block of billiard

chalk to charge the brushes with.

We will wa n t the pegwood sticks, s o me p i t h , tissue p a p e r , a n d

a clean soft linen cloth.

Lastly we require some means of keeping the parts perfectly

clean after we have finished with them. Small glass dome-shaped

covers can be purchased for this purpose but alternatively a good

method is to obtain a clean shallow pan, large enough to contain

all the parts in their groups, and cut a piece of white paper to fit

in t h e b o t t o m . T h e n we will wa n t a piece of clear glass to place

over the pan as a dust cover.

Now that our tools and materials are laid out on the bench we

can commence the process of cleaning.

WATCH AND CLOCK REPAIRS

Pour some cleaning fluid into the washing tray and replace the

lid of the container. Take both cleaning brushes and charge them

with chalk by stroking the billiard chalk a few times with the

bristles. Make sure the full length of the brushes is treated.

With the exception of the dial, the hands, the pallets of a lever

escapement and the mainspring barrel assembly, all the parts are

immersed in the cleaning fluid. By holding the parts with tweezers

and moving them about dirt and old oil will be washed off.

The parts are then lifted out and placed on tissue paper to

drain. In a warm room the cleaning fluid will soon evaporate

leaving the parts clean and dry.

Each part is then polished by brushing to ensure absolute

cleanliness. Bearing holes are cleaned with a pegwood stick shaved

to a fine point, and pivots are cleaned by rotating them in a pith

stick.

Once the parts have been removed from the cleaning fluid they

must not be touched by hand. If it is necessary to hold them in

the hand do so with tissue paper, otherwise hold them to the

bench with tweezers when working on them. This is important

because finger-marks can cause unsightly stains.

After each part has been cleaned and polished it must be

examined carefully through an eye-glass for signs of dirt, corrosion

and damage and if all is well it can be placed under cover in the

tray for cleaned parts.

Note the position of the index and then dismantle the balance

cock. Place it on its back on the bench and hold it down by the

tip of a finger whilst removing the two small screws. In some

movements these screws are very small and great care must be

exercised in their handling to prevent loss.

If the balance is fitted with shock-absorbers then reference

must be made to Chapter

12 for instructions on dismantling.

When the balance cock has been taken to pieces the parts are

transferred by tweezers into the washing bath. The parts are left

to soak and in the meantime the balance is dismantled.

Make a note of the relative position of the hairspring collet

to the balance wheel so that it can be replaced on the staff in the

OVERHAULING AND CLEANING

same position. Hold the balance wheel between the tips of

the first and second fingers and the ball of the thumb. Insert the

blade of an oiler or a very small screwdriver into the slot of

the collet. Slight pressure should widen the slot and permit the col

let to be withdrawn from the balance staff. Place the balance

wheel and the hairspring into the washing bath.

The parts of the balance cock can now be lifted out of the bath.

Place each part on a piece of tissue paper and allow the cleaning

fluid to drain off and be soaked up by the tissue. The cock can be

dried in the linen cloth.

Hold the balance cock in tissue paper and brush gently with

the medium brush. Apply the brush in straight strokes and keep

the grain flowing with the length of the cock.

The remaining parts are laid on the sheet of white paper and

are held by the tweezers whilst being brushed. Use the soft brush

for these parts.

The jewel bearing in the balance cock must be cleaned and to

do this a piece of pegwood is shaved to a fine point, inserted into

the bearing and is given a turn or two applying very little pressure.

Remove the pegwood stick, shave off the dirt and insert it again,

this time from the other side.

Assemble the balance cock and replace the index in its original

position.

Now lift out the balance wheel and allow it to drain off on the

tissue paper. Brush the wheel carefully with the medium brush

taking great care to avoid knocking the pivots. In some move

ments the pivots are so fine the slightest knock will result in

breakage.

Finish off by polishing the pivots with a pith stick.

Place the hairspring on tissue paper and lay another piece of

tissue paper on top. Continue to renew the paper until all cleaning

fluid has been absorbed. Then lightly dab between the coils with

the tip of the soft brush.

Examine the balance wheel, roller or cylinder, and hairspring

very carefully and then replace the hairspring collet on the

balance staff in its original position.

WATCH AND CLOCK REPAIRS

Lift out the pallet cock and screws and clean them in the same

way. The pallets

(if from a lever escapement) have not been

immersed in the cleaning fluid. This is because some shellacs are

not impervious to gasoline and it is therefore considered better

not to soak them but to immerse them in the fluid, agitate them

to remove the dirt and lift them straight out again.

Place them on the tissue paper to dry. Hold them with the

tweezers and thoroughly brush them with the soft brush. Finish

off by polishing the pallet stones with a pith stick.

Clean the leaves of the escape wheel pinion with a pointed

pegwood stick. Rub the stick up and down until the leaves are

bright. Well brush the wheel with the soft brush and then clean

each tooth and both pivots with the pith stick.

The teeth of an escape wheel fitted to a pin-pallet escapement

call for special attention. The constant action of the pallet pins

working in the escape wheel teeth causes a build-up of dirt at the

base of the teeth. This dirt is forced into the corners by the pins

and becomes quite hard.

Normal soaking and brushing is insufficient to remove the dirt

and unless it is removed the shake of the roller will be affected.

If a sharp knife blade is placed at the root of each tooth and

lightly drawn across, the dirt will come away. Handle the blade

with care because careless handling can result in the removal of

metal which would have a serious effect on the escapement.

Finish off with a stiff brush.

Proceed with the rest of the movement in the same way making

sure each part is examined under the eye-glass when it is finished.

Remember that the large pieces such as cocks, bridges and plates

can be dried in the linen cloth.

The barrel is next to receive attention. Before removing the

barrel cover make a note of its position in relation to the barrel.

It is essential that the cover be replaced in the same position.

Insert the blade of a screwdriver in the slot of the barrel cover

and gently ease the cover off.

Before proceeding any further a close inspection of the main

spring and barrel is necessary. If the cover of the barrel is a good

OVERHAULING AND CLEANING

fit and the condition of the mainspring is clean and well oiled,

and no dirt is present, it is unnecessary to remove the spring.

To take a mainspring from its barrel and allow it to fully

expand does more harm than all the good that cleaning can do.

If the spring looks clean and healthy, leave well alone.

If, however, it is decided that the spring must be removed, then

proceed as follows.

Grip the arbor in the pin-vice and with a slight clockwise turn

to free the hook, lift the arbor out.

The removal of the spring must be done with care otherwise it

may be rendered unfit for further use.

Hold the barrel in the left hand and a pair of strong tweezers

in the right hand. Grip the centre coil of the spring and gently

ease it out.

When the spring shows signs of moving without assistance

hold it back with the ball of the left thumb and slowly release the

pressure.

By this means the spring will unwind itself from the barrel but

at a controlled rate.

If the centre was to be pulled right out and the spring allowed

to fly open it would adopt a conical shape which would render it

unsuitable for further use.

In any case, a spring that is let down rapidly after being under

tension for a considerable period invariably breaks.

Wash the parts in the cleaning fluid, brush the barrel and

polish the arbor with the pith stick. The spring is wiped with tissue

paper.

Take a piece of tissue paper and fold it over. Place it around

the outer coil and with a pair of tweezers slide the paper along the

coils to the centre. Do not open the spring but allow it to retain

its natural curvature.

There now only remains the dial to be cleaned. There is very

little that can be done however.

If the dial is enamel and has smeary marks on its face it may be

wiped with a soft cloth moistened with the cleaning fluid and

then lightly polished with a dry piece of the same cloth. Nothing

WATCH AND CLOCK REPAIRS

can be done with a crack but if dirt has found its way into a crack

showing it up as a thin black line the dirt can be removed by

brushing along the crack under running water.

Any attempt to clean a silver or gilt dial almost always results

in the dial looking worse. It is safer to leave these alone. A gold

dial can be wiped with a moist chamois leather.

This completes the cleaning of the movement and the next step

is to assemble the parts. The oiling will be done progressively

during the work of assembling the movement.

We will start with the mainspring and barrel. The correct

method of fitting the spring into its barrel is by using a mainspring

winder. There are a number of ways in which a winder can be

used.

The eye of the spring is attached to the hook of the winder and

the spring is wound in the hand, a firm hold being maintained by

finger pressure to prevent it unwinding. The winder is unhooked

from the spring and by careful manipulation the spring is trans

ferred to the barrel.

Another method is to attach the spring to the winder as before.

Hold the barrel in the left hand against the spring and in a

position ready to receive the spring when wound. Commence to

wind holding the spring with the fingers and when the diameter

of the spring is less than that of the barrel, the barrel will move

forward over the spring.

The type of winder commonly used in the United States em

ploys a set of dummy barrels with plungers. A dummy barrel,

smaller in diameter than the barrel of the watch, is selected. The

spring is wound into the dummy and then transferred to the

watch barrel by pushing it out with the plunger.

It does not follow that without a mainspring winder it is not

possible to fit the mainspring. By placing the arbor in the barrel

and gripping it behind the barrel with a pin-vice, the eye of the

mainspring can be hooked to the arbor and can then be wound in.

This method, although practised, is not recommended because the

angle at which the spring is fed into the barrel tends to create

distortion. Due to the very small clearances between a main-

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spring and the barrel cover it will be appreciated that an almost

imperceptible amount of distortion towards being conically

shaped can result in the edge of the mainspring fouling the

cover. This would cause the spring to stick and have a jerky

action.

There is yet another method of fitting a mainspring, and it is

by hand. Again, the method is bad practice for the same reason

given above. The centre of the spring is positioned in the barrel.

The barrel is held between the first finger and thumb of each hand

and rotated and at the same time the spring is fed in by the ball

of the thumb.

It has been established that one of the main causes of main

spring breakage is rust. A very tiny speck will weaken the spring

and under tension the spring is liable to break at that point.

Rust can result from handling and therefore it is important

that the mainspring be touched by hand as little as possible.

Place the arbor in position and make sure the eye of the spring

is over the hook of the arbor. The centre coil should now be

wrapped round the arbor. If it is not, remove the arbor and close

the centre of the spring slightly. When the centre coil is correctly

set it is necessary to push it to one side to get the arbor in.

Charge the watch oiler with oil and touch it three times around

the edges of the spring.

Let us pause a moment here because this is the first time any

reference has been made to the application of oil, and we must

therefore have an understanding of the subject before we can

proceed any further.

There are four things to consider; where to oil, choice of oil,

quantity to apply, and lastly how to apply it.

Taking them in that order then we can say that oil is required

wherever two or more surfaces are rubbing together. Ideal

lubrication can be better understood if we imagine two perfectly

flat surfaces, one on top of the other, completely separated by a

thin film of oil. If a means of retaining that film of oil can be

provided, then the top plate can be moved over the bottom plate

with almost no resistance.

WATCH AND CLOCK REPAIRS

Below is a table listing the points that require lubrication in a

wristlet watch such as the one illustrated. This will serve as a guide

for other watches.

Top Grade Watch Oil

Top Grade Clock Oil

Escape wheel pivot holes

Crown wheel sleeve

Fourth wheel pivot holes

Cannon pinion

friction

Third wheel pivot holes

groove on centre wheel

Centre wheel pivot holes

Pull-out piece pin

Three teeth of the escape

Winding stem pivot

wheel

Pull-out piece

Balance pivot holes

Return bar stud

Return arm

Barrel arbor pivot holes in

plate, bridge, barrel and

cover

Mainspring

The second consideration is also dealt with in the table in that

the choice of oil is given.

As to the quantity, this, of course, cannot be stated in degrees

of measurement. One drop of watch oil and one drop of clock oil

from a large watch screwdriver is sufficient to lubricate two or

more watches as illustrated.

Too much emphasis cannot be placed on the need to guard

against over-oiling. When one bears in mind it is only the areas

of frictional resistance that need oiling and then consider how

very small some of these areas are, it will be appreciated that the

correct amount of oil to apply in these cases would be difficult to

see without the aid of an eye-glass.

Excess oil creeps on to watch parts causing minute particles

of dust and fluff to adhere. This accelerates the rate of drying up

the oil. Parts of the watch that it is essential should be free of oil

OVERHAULING AND CLEANING

become contaminated, such as the escapement banking pins, the

ruby pin, the hairspring and so on.

The aim in cleaning and oiling a movement is to finish with a

meticulously clean and perfectly dry watch with just sufficient

oil applied in exactly the right spots.

If two lubricated surfaces, one flat and the other curved, are

placed together the oil will concentrate around the apex of the

curve. This attraction is the capillary action of a fluid and is the

reason for an oiler being shaped as it is. When the oiler is charged

with oil, the oil remains on the end and does not run up the blade.

Then when the tip of the oiler is brought into contact with the

part to be lubricated, the capillary action will cause the oil to be

transferred.

To oil a watch movement two oil cups are needed, one for

watch oil and the other for clock oil. Dip the large watch screw

driver into the bottle of watch oil and transfer one drop to the cup

for watch oil. Charge the clock oil cup in the same way. Wash

the screwdriver in the cleaning bath before using it again.

Make sure that the oiler is free from oil before touching it to

the oil in the cups. This will enable you to control the amount of

oil picked up. If the oiler blade is moist with oil with perhaps a

smear along the blade, then the effect of touching the oiler to the

oil is to pick up an excess amount.

If this should happen, no control can be exercised over the

amount of oil deposited by the oiler when applying it to the

movement because the capillary action will attract almost all of

the oil and deposit it on the watch.

Now that we have a better knowledge of the technique of

oiling we can continue assembling the movement.

Now that the mainspring has been oiled the barrel cover may

be snapped on. Covers are made to fit in one particular position

and it is important that the cover is always replaced in this

position.

Many are marked with dots so that when the dot on the cover

is opposite the dot on the barrel the two are in the correct position

in relation to each other.

WATCH AND CLOCK REPAIRS

Make sure the cover fits square and flush. Hold the arbor in the

brass-faced pliers and turn it in the direction of winding until you

feel the hook on the outer end of the spring find its anchorage on

the barrel wall. Apply a touch of oil to each end of the arbor

where it operates in the barrel.

Place the bottom plate on the movement stand. Insert the

escape wheel followed by the fourth and third wheels. Oil the

lower centre pivot and insert the centre wheel. Fit the train wheel

bridge taking care the recess does not catch the third wheel as

the bridge is lowered.

When fitting the train wheel bridge place a piece of tissue paper

on it and press down very lightly with the finger. The top pivots

of the wheels can be guided into their bearings with a pair of fine

tweezers and the bridge will then lower into position without any

forcing.

Oil the pull-out piece screw and fit it in position. Insert the

barrel and refit the barrel bridge. Oil the barrel arbor in the

bottom plate and in the barrel bridge.

Lubricate the seating of the transmission wheel and replace

the transmission wheel and the barrel ratchet. Don't forget that

the transmission wheel screw will probably have a left-hand

thread.

Now turn the movement over. Oil the centre arbor and fit the

cannon pinion. Insert the crown wheel and the castle wheel. Oil

the winding stem and fit it in position. Fit the pull-out piece.

Oil the ratchet teeth and the castle wheel groove. Oil the return

bar stud and replace the return bar and the spring. Lightly oil the

keyless work.

Check the end-shake and the side-shake of the wheel train,

and oil the top and bottom pivots. Wind up the mainspring one

click of the ratchet and make sure that the wheel train has

complete freedom of movement.

Fit the pallet and the pallet cock and oil the pivots. Wind up

the mainspring about four clicks and press the lever lightly on one

side with the tweezers. Make sure that the lever runs to the

opposite banking pin with a lively action.

OVERHAULING AND CLEANING

The balance now has to be fitted to the balance cock. During

the dismantling it was considered inadvisable to unpin the hair

spring from the stud and therefore all that is now required is for

the stud to be replaced in the balance cock.

Some studs are secured to the cock by a screw whilst others are

a push fit. Among those that are held by a screw will be found

some that are machined with a straight groove into which the end

of the screw is located. This ensures that each time the stud is

replaced it always takes up the same position.

With the others it may be necessary to turn them slightly one

way or the other to line up the outer coil with the index pins.

Hold the balance cock in the tweezers and allow the balance

to hang from it. Lower the balance into the movement and

with careful manipulation the balance will find its own position

as the cock is lowered.

Place a piece of tissue paper on the cock and very gently press

down with the finger making sure that the balance has freedom

of movement at all times.

Before the cock is fully down the balance will probably com

mence to vibrate. Screw the cock down and check the beat of

the movement. If the beat is irregular the balance must be

removed and separated from the cock and the hairspring collet

moved round the balance staff into a new position. This is dealt

with in greater detail in Chapter

12.

When the beat is correct remove the balance for the last time.

Oil both pivot holes and replace the balance.

Replace the motion work and refit the dial. The movement is

now ready for fitting into its case after which the hands can be

replaced.

Wind up the mainspring, set the hands to indicate the correct

time and put the watch to one side for a check on time-keeping.

Any small adjustments that are needed can be made by altering

the position of the index.

When the watch is to your satisfaction there is only one more

thing to consider and that is whether or not it is necessary to seal

the case.

WATCH AND CLOCK REPAIRS

If the watch is to operate in tropical conditions where the

humidity is high, or if the wearer is employed in conditions that

subject the watch to steam such as a laundry, or if dry dusty

conditions exist in a concentrated form, then to seal the case

would be a distinct advantage.

Make up a small quantity of a mixture of four parts of beeswax

to one part of Vaseline. Smear a thin film of the wax between the

joins before closing the case. A small application around the

winding stem at the top will complete the treatment.

CHAPTER SIX

Wheel trains

ONE vibration of a balance wheel is the completion of movement

in one direction. The total number of vibrations in one hour can

be calculated by counting the number of teeth in the wheels and

number of leaves in the pinions.

Because the teeth of the main wheel in mesh with the centre

wheel pinion are only a means of transmitting power to the train

of wheels, timing is calculated from the centre wheel.

Let us assume the train is as shown in figure 24. Because the

centre wheel has eight times as many teeth as the pinion of the

third wheel it follows that one revolution of the centre wheel

causes the third wheel to rotate eight times.

Following on from this, if the third wheel has 75 teeth and the

fourth wheel pinion

10 leaves, then one revolution of the third

wheel is equal to 7 1/2 revolutions of the fourth wheel.

So far then, we can say that the fourth wheel revolves 8 x 7 1/2 =

60 times to one revolution of the centre wheel.

Finally we come to the escape wheel. The escape wheel pinion

has 8 leaves and is driven by the fourth wheel that has

80 teeth.

One revolution of the fourth wheel will therefore cause the escape

wheel to revolve

10 times.

Fig. 24. Wheel train: (a) centre wheel 80 teeth (b) 3rd wheel 75 teeth,

pinion 10 leaves (c) 4th wheel 80 teeth, pinion 10 leaves (d) escape wheel

80 teeth, pinion 8 leaves.

WATCH AND CLOCK REPAIRS

Progressive calculations now show that one revolution of the

centre wheel is equal to 8 χ 7 1/2 χ 10 = 600 revolutions of the

escape wheel.

If there are 15 teeth on the escape wheel, and each tooth is

equal to two vibrations of the balance wheel, then the total

Fig.

25. Fitting new tooth.

number of vibrations to one revolution of the centre wheel is

8 χ 7 1/2 χ 10 x 15 χ 2 = 18,000.

This is more simply expressed as

80 χ 75 χ 80 χ (15 χ 2)

= 18,000

10 χ 10 χ 8

If the number of teeth and leaves on the wheels and pinions

are recorded when a watch is dismantled, and the number of

vibrations each hour calculated, adjustments for correct timing

can be made when the movement has been assembled.

In the example given, 18,000 vibrations were made in one hour

= 300 in one minute or 100 in twenty seconds.

Providing a watch that maintains accurate time is available and

fitted with a seconds hand, the beats of the watch undergoing

overhaul can be counted during a period of twenty seconds and

adjustments made as necessary.

WHEEL TRAINS

Sometimes inspection of the movement reveals a broken wheel

tooth.

Broken teeth are not common failures but when they do occur

it means a repair or a new wheel. Because of this an attempt at a

repair will be good practice and if the completed job is not good

enough nothing has been lost; a replacement wheel can still be

obtained.

The repair sequence is illustrated in figure

25. The broken

tooth is shown at

(a). With a thin file cut a slot as at

(b). The

teeth on one edge of the file can be ground off to assist in filing

the corners of the slot square.

A piece of brass pin-wire is selected and two flats are filed

opposite each other until the wire fits tightly into the slot as at

(c). Cut off the surplus wire and make sure the remainder is

parallel to the face of the wheel.

Carefully raise the temperature of the wheel in the repair area

by touching it against a soldering iron and then apply some

soldering flux. When the wheel is hot enough place a small piece

of solder on the base of the new tooth and allow the solder to

penetrate through the join to the under-face of the wheel.

Allow to cool off and then file the tooth to shape as at id).

After the repair make sure that all traces of soldering flux and

filings have been washed and brushed away.

CHAPTER SEVEN

Hands, dial and motion work

THE motion work consists of a steel cannon pinion, a brass hour

wheel and a brass minute wheel and pinion

(Fig.

26).

The cannon pinion has a groove machined round it and the

base of the groove is burnished inward causing a bulge. The

centre wheel arbor has a corresponding groove cut round it and

when the pinion is pushed on to the arbor the internal bulge snaps

into the arbor groove and provides a friction tight fit.

The minute wheel and pinion revolve on the minute wheel post

which is fixed to the bottom plate.

The cannon pinion drives the minute wheel and the minute

wheel pinion drives the hour wheel which revolves freely around

the cannon pinion.

The hour hand is pushed on to the end of the hour wheel pipe

and the minute hand is fitted over the end of the cannon pinion.

The gear ratios are such that the hour wheel revolves once to

every twelve revolutions of the cannon pinion.

By applying the formula in Chapter

6 for calculating gear

ratios we find :

Fig. 26. Motion work.

HANDS, DIAL AND MOTION WORK

6 1

Minute wheel teeth x Hour wheel teeth

= 12

Minute wheel pinion leaves χ Cannon pinion leaves

The most usual wheel trains employed in motion work are

shown in the following table.

Keyless Genevas and

Modern Keyless

Key-wind watches

English Levers

Cannon Pinion

Minute Wheel

Minute Pinion

Hour Wheel

Fig. 27. Hands.

MOTION WORK TRAINS

Hands

(Fig.

27). All too often the fitting of hands receives

insufficient attention. Badly fitted hands are a common cause of

watch failure. They can cause a watch to function intermittently

or to s t o p completely. If a wat ch with a loose-fitting h a n d is

subjected to slight shock, the hand can swing into a new position

and register incorrectly.

A careful functional e x a m i n a t i o n of the h a n d s before dis

mantling will frequently reveal the cause of the trouble. Once the

hands have been removed the evidence is destroyed. This inspec

tion is dealt with fully in Chapter

5 a n d so we will c o nc e r n our

selves here with the correct fitting of replacement hands.

Seconds hand. To fit a new seconds hand to its pivot the pipe

must be broached. This is done by holding the pipe in a pair of

WATCH AND CLOCK REPAIRS

hand-tongs (Fig. 28), and enlarging the hole with a pivot broach.

Only the lightest pressure is needed whilst rotating the broach

between finger and thumb.

To reduce the length of a pipe, drill a hole in a strip of brass

just large enough to allow the pipe to pass through. Place the

hand on the filing block, pipe uppermost, and lower the brass

strip over it. The exposed end of the pipe can now be filed.

The internal burr is removed by using the broach as before.

Fig. 28. Hand-tongs.

The external burr can be taken off by leaving the hand on the

broach and using a pivot file as for pin-filing.

(Chapter

1.)

The outside diameter of the pipe is reduced by using the same

pin-filing technique.

Hour hand. The socket of the hour hand should be a push fit

over the pipe of the hour wheel. To enlarge the socket hole do

not use a broach because this method produces burrs. The socket

is held in the hand-tongs and the hole enlarged by a rat-tail file.

Alternatively, the diameter of the hour wheel pipe can be reduced

in the turns. If when this is done the hour wheel pipe is found to

be gripping the cannon pinion, the hour wheel pipe must be

lightly broached with the hour hand in position.

It may be found that the outside diameter of the hour hand

socket is too great to clear the hole in the dial. In this event the

socket should be reduced in the turns.

Minute hand. Cannon pinions are either square-ended or

round-ended, and the hole in the minute hand centre boss must

be the same. To fit a minute hand to a square ended cannon

HANDS, DIAL AND MOTION WORK

pinion a square file is used to enlarge the hole of the centre boss.

The file is used in the corners of the square hole and not on the

sides, making one stroke in each corner at a time. This will assist

in maintaining the square shape.

To enlarge a round hole, use a rat-tail file rather than a broach.

If the thickness of the centre boss needs to be reduced this can

be done by careful filing, but a more satisfactory way is in the

turns.

When opening out the holes of the hour hand and minute hand,

care must be taken to keep the hole square with the hand, and not

to remove too much metal. The finished result should be a push

fit. In the case of the seconds hand the very lightest nip of the

pipe on the pivot is sufficient.

Enamel dials. Due to the fragile nature of the layer of enamel,

these dials must be treated with care. If the enamel is cracked, it

is best left alone. Small pieces can be put back in position by

using glue. If a small piece is missing the space can be filled in

with dial enamel. The cement is warmed and run on to the dial

base and allowed to set. The cement is then filed down to the level

of the surrounding enamel. Hold the dial by one of the feet in a

pair of pliers and pass the dial through a spirit flame. This will

momentarily melt the cement which will set with a glossy

surface.

To enlarge a dial hole a cone-shaped emery stick is used first

to produce a chamfer. These emery sticks are made specially for

this purpose and can be obtained from your supplier. The hole

is then made larger by filing with a rat-tail file moistened with

turpentine.

A broken foot can be replaced. The enamel at the back of the

dial is removed from the affected area by scraping with a sharp

pointed tool. A new foot is made from a length of copper wire and

is silver-soldered to a small disc of copper a little larger in

diameter than the wire. The new foot is now soft-soldered into

position. Marks or discolouration are best removed with warm

soapy water.

Gold and silver dials. These dials are very delicate and should

Components

Screws

100

Plate

5105

Barrel bridge (cheesehead,

105

Barrel bridge

polished)

110

Train wheel bridge

5110

Train wheel bridge (cheese-

121

Balance cock

head, polished)

125

Pallet cock

5121

Balance cock (cheesehead,

180

Barrel complete with arbor

polished)

182

Barrel and cover

5125

Pallet cock,

(cheesehead,

185

Barrel

polished)

190

Barrel cover

5311

Top balance endpiece

195

Barrel arbor

(countersunk, polished

201

Centre wheel complete

ends)

210

Third wheel complete

5330

Bottom balance endpiece

220

Fourth wheel complete

(countersunk, polished

240

Cannon pinion

ends)

250

Hour wheel

5415

Barrel ratchet

260

Minute wheel

5420

Top crown wheel

(trans

301

Regulator index

mission wheel)(lefthand)

311

Top balance endpiece

5425

Click

330

Bottom balance endpiece

5443

Setting bolt (pull-out piece)

401

Winding stem

5445

Setting bolt spring

(pull-

407

Castle wheel

out piece spring)

410

Winding pinion (crown

5721

Balance

wheel)

5738

Hairspring stud

415

Barrel ratchet

5750

Dial edge

420

Top crown wheel

(trans

mission wheel)

422

Crown wheel collar

425

Click

Jewels

430

Click spring

630

Top balance

435

Return bar

631

Bottom balance

440

Return bar spring

615

Escape top

443

Setting bolt (pull-out piece)

616

Escape bottom

445

Setting bolt spring (pull-out

620

Top pallet

piece spring)

621

Bottom pallet

450

Intermediate wheel

646

Entry pallet

705

Escape wheel complete

647

Exit pallet

710

Pallets complete

610

Top fourth

721

Balance complete

611

Bottom fourth

723

Balance staff

605

Top third

730

Roller

606

Bottom third

734

Hairspring complete

601

Top centre

738

Hairspring stud

602

Bottom centre

770

Mainspring

648

Roller (impulse pin)

KEY TO PLATE 1

HANDS, DIAL AND MOTION WORK

be handled in soft tissue paper. Finger marks can be removed

from gold dials by light rubbing with tissue paper. Silver dials

discolour badly with age. Both types of dials may be washed in

warm soapy water and dried in boxwood dust. They should never

be brushed or rubbed with a cloth.

Broken feet can be replaced by soft-soldering a length of copper

wire into position.

Filing is the only method of enlarging holes. A rat-tail file is

used inserted from the face side.

CHAPTER EIGHT

Keyless work

KEYLESS work as the name implies is a method of winding the

mainspring without the use of a key.

There are a few ways in which this is done but we will consider

the method most used in wristwatches.

Figure

29 shows a typical arrangement of keyless work. The

winding stem is threaded at one end for the winding button. At

the base of the threaded portion is a shoulder that works in the

movement plate. Beneath this shoulder a groove is cut to receive

the pin of the pull-out piece, and beneath the groove is another

shoulder that locates the crown wheel. The remaining length is

squared to take the castle wheel with the exception of the end

which is turned down to form a pivot.

The pull-out piece is retained in position by a shouldered

screw. The crown wheel rotates on the lower shoulder of the

winding stem. The castle wheel has a square hole and although free

to slide up and down the squared portion of the winding stem

must nevertheless rotate with it. The check-spring is held in

position at one end by a screw, and the other end is positioned in

the groove of the castle wheel. The upper face of the castle wheel

and the lower face of the crown wheel are cut with identically

shaped ratchet teeth and are in mesh with each other. The upper

edge of the crown wheel is cut with gear teeth which mesh with

the transmission wheel. The bottom face of the castle wheel is

cut with gear teeth and can be meshed with the intermediate

wheel.

The normal position for this mechanism is as shown in figure

29. Turning the winding button and stem will cause the castle

wheel to rotate. Because the check-spring is holding the castle

wheel in mesh with the crown wheel the crown wheel must

rotate as well.

In turning the crown wheel, the transmission wheel on the top

KEYLESS WORK

plate is rotated which, through the ratchet wheel, causes the

mainspring to be wound.

If a sharp pull is given to the winding stem, the pull-out piece

will turn with its screw causing the check-spring to be pressed

downward. This position is maintained by the end of the pull-out

piece dropping into a step cut in the edge of the check-spring.

Fig. 29. Keyless work. 1. Winding button. 2. Winding stem. 3. Crown

wheel. 4. Castle wheel. 5. Intermediate wheel. 6. Hour wheel. 7. Minute

wheel. 8. Return bar. 9. Check spring. 10. Pull-out piece. 11. Pull-out

piece screw.

Handbook of Watch and Clock Repairs (1972) - page 2