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Causes Of Stoppage Of Watches

( Originally Published 1918 )



Small Faults.—A watch may be cleaned carefully and well repaired, yet may, when put together, have a bad action, or stop in the workman's hands or under his very eyes. Such watches often give more trouble and waste more time than has been previously spent on cleaning and repairing them.

Beginners, after they have vainly looked all round such a watch, are apt to give it up as a " mystery." There are no mysteries in watchwork. A stopping watch has a fault some-where, however small, and it must be found.

A workman who looks out for faults as he takes a watch apart is not troubled with these " stoppers " so often as the careless man. An escapement should always be examined and tried before taking apart; all wheels should be examined as to endshake and side play, marks of fouling each other or the plates looked for. As the watch is put together again, everything should be tested as it is put in.

Often the cause of stoppage is a dial pin fouling a train wheel, or a screw put in its wrong place, its point going too far through somewhere. Stoppages in the train are most easily found. Taking care not to start such a watch, with a needle try the scape wheel and see if it has "power" on it. If not, try the fourth, third, centre, and so on in succession, until the point is found at which the power disappears. This gives a clue, and a bent tooth, a bent pivot, a tight endshake, or some cause of fouling must be looked for in that wheel or pinion. A watch that stops once per minute probably has a fault in the fourth wheel or pinion. If once per hour, it may be the centre wheel or pinion or the motion work. If every fifteen beats, a damaged scape tooth or dirt in the scape pinion.

When power appears to go off at the barrel itself, it may be that the stopwork jams. A little roughness on the centre stop finger of Geneva stopwork is liable to catch the points of the star wheel. A shallow depth between stop finger and star wheel will also cause it to jam. The mainspring may bind in the barrel, or a cap screw point may be too long and bind it.

If a fault is suspected in the train and nothing can be seen to account for it, run each wheel separately in its frame to see that it has perfect freedom; then each two wheels together, and try all depths.

A watch that seems to have plenty of power but has no action has a fault in the escapement. After trying the scape depth, the banking shakes, run, and endshakes, see that the lever and roller do not touch, that there is no oil between the lever and the plate, that the hairspring lies flat and -true, free of the balance, the plate, and everything else. If no fault can be found there, run the balance in its pivot holes alone, with the roller and hairspring removed. Let it run slowly, and observe how it stops. A bristle from the brush may be found sticking in its rim, or in the plate, just touching it. The balance rim may touch the fusee chain in a 4 plate. Then put on the roller and let the watch go to half time, without the hairspring, and see if it acts freely and does not catch anywhere.

A pivot may not corne quite through a jewel hole, or the hairspring collet may touch the balance cock.

Much can be learned by listening carefully to the beat in various positions. If the balance is foul of anything, a striking will be heard. If a Geneva horizontal scrapes in one position, it is probable that the scape wheel touches either the bottom or top of its passage in the cylinder.

A watch that stops in one position only has generally a fault in the escapement. If the pivots and jewel holes are quite right, it is a fault caused by the movement of the balance, scape wheel, or pallets, owing to their endshake or side play. Some-thing that is quite free with the endshakes one way fouls when they are the other way. Excessive endshakes may be present.

Note if the action is equal dial up and dial down. Any falling off will indicate a fault. To observe the action dial up, a small piece of mirror laid upon the bench is extremely useful, as the watch can be held steadily over it and the action observed at leisure.

A lever watch that falls off in action when the balance leans towards the lever has probably a fault in the roller and lever depth. The ruby pin may be a round one and not enter the notch properly. A flatted pin will cure this. There may be not enough, or too much, banking shake, or a roughness on the roller edge.

Watches that go all right lying down and hanging up, but stop in the pocket, will often be found to be too shallow in the safety-pin action. The safety pin in the lever can jam against the roller edge. Also, in such a case, look to the pallet depth and see if it mis-locks on any teeth, as this causes the safety action to jam.

If a watch stops when just wound up, see to the maintaining work, also that it is perfectly in beat and that the safety action is correct.

In full-plate English watches the barrel may rise just a little above the plate and foul the under corner of the balance cock, or the balance rim, in certain positions. If the main-spring is of the American pattern and has a brace, the top pivot of the brace may project and foul the balance rim or scrape the barrel bar. The point of the guard pin in the lever may touch the under side of an undersprung index.

The chains of these watches may scrape the back of the potance, or the inside of the cap. The barrels of f plate going-barrel watches may just touch the case edge and cause binding. The cannon pinion may be too low, and its teeth may scrape the plate.

The dial may press upon and bind the minute wheel or some of the points of the lower pivots.

Hands should always be looked at to see if they touch the dial or the glass and are free in the dial holes.

Some new machine-made English levers give a lot of trouble by stopping from the least dirt. It gets round the train-wheel pivots and jams them tight. This is caused by rough plates and rough pivots. Polish all the pivots and stone the plates round the pivot holes quite smooth. The gilding on the plates of these watches is like a honeycomb.

The plates seem to be pickled to frost them deeply before gilding, presumably to cover up a want of smooth finish. The result is that grit is held by the surfaces of the plates and jams under the square pivot shoulders of the train wheels, as in Fig. 181.

If dial pins are not pushed in quite tight and do not fit well, they often work loose and come out.. Being in the case, they rattle about until they get under one of the wheels and there stick. When a stopping watch is brought in minus one dial foot pin, look at once to see if it is not somewhere in the wheelwork. Similarly a small screw, if it works out, may jam the wheels.

A train wheel or pallet pivot that is short and does not come through its brass hole is apt, in an old watch, to wear a step in the hole. When much worn in this way, the step sometimes jams the pivot by stopping its endshake, as in Fig. 18e. The remedy is to broach out and bush the hole.

In the holiday season, when people go to the seaside, sand is a frequent cause of watches stopping. A little gets in the pocket and finds its way into the watch case. One grain is sufficient to stop it, though, as a rule, many grains find their way in. A single grain fixed between two wheel teeth as a rule causes the stoppage.

Duplex watches and pocket chronometers, even when set in beat as carefully as possible, will occasionally stop in the pocket. Being single-beat escapements, it only needs a movement that brings the balance to rest at the right moment to stop them.

Verge conversions that have no maintaining work will also stop during winding sometimes. These should always be very carefully set in beat, to avoid this trouble as far as possible.

Watches with heavy escapements are also liable to stop when the hands are put back, especially if they move stiffly. For this reason, pocket chronometers should always have the hand work left easy, just tight enough for them to carry with certainty, but no tighter.

In some old English 3/4 plates the lever lies much too close to the pallet cock—so close that the oil applied to the top pallet pivot is almost sure to be drawn between the lever and the cock. The best way to serve them is to file away the under side of the cock each side of the pivot hole, and, if possible, turn a cone hollow around the top pivot in the body of the pallets.

Magnetized Watches.—In these times, when there is so much electrical machinery about, watches are often found to be magnetized.

If all the steel parts should be very strongly magnetic, the watch will not go at all, the balance being attracted by the screws, etc., around it, and the hairspring adhering to the balance. When only slightly magnetized, the watch will go, but the timekeeping will be very erratic. A watch becomes magnetized through being brought into the field of a powerful electro-magnet, such as a running dynamo or motor. To detect it, place a small charm or pocket compass flat over the balance cock, with the centre of the compass corresponding with the centre of the balance. If magnetic, the compass needle will vibrate as the balance does, or perhaps fly round and round. If not magnetic, the needle will be quiet. A perfect protection to a watch is an iron box, or what is commonly known as a " tin" box. It follows from this that ordinary watches, if in "gun-metal" cases (oxidized or blacked iron), and full hunters are perfectly protected from magnetic influence.

To demagnetize a watch, it should be revolved rapidly and brought into the field of a powerful magnet—say a dynamo and gradually withdrawn. One way of effecting this is to first wedge the balance with tissue paper ; then fasten a string to the bow and twist. it up tight; suspend the watch by the twisted string close to a running dynamo, and let it untwist rapidly. As it does so, withdraw it out of reach. This is only a rough way. If a magnetized watch is sent to an electrician, he will demagnetize it more thoroughly for a fee of about as. 6d.

Careful tests show that once a watch is magnetized it is never quite free again. A fine watch with a close rate is for ever spoiled. The only perfect cure is to heat all the steel parts to redness, re-harden, and polish them again. This involves fitting a new balance, hairspring, mainspring, etc., and in most watches is not worth doing.

Karrusel Watches.—These watches have a few faults of their own that often stop them. The revolving carriage carrying the escapement must be dry, clean, and quite free. Where it bears and rubs on the plate, both top and bottom, must be channelled out by turning, letting it bear on circles only. These must also have no gilding on them, being stoned off smooth where the friction comes. Gilding wears off and works up into a black powder and causes choking.

The edge of the carriage is sometimes found to foul the end of the third wheel cock and the tops of the barrel teeth. The third cock is easily filed to free it. To free the barrel teeth, the barrel is best put in a step chuck and the teeth-tops bevelled down. The top third pivot hole is also rather liable to be left dry, and must be oiled before putting in the third wheel.

Bad Mainsprings.—A watch that has a poor action, the balance vibrating less than one complete turn, is always liable to stop from the least cause. Often such a watch will be found to have a poor, cramped up mainspring, and can be greatly improved by changing it for a good quality lively spring of the same thickness. Nothing pays better in watch materials than to keep a good quality of mainspring. A spring costing 4s. 6d. or 6s. per dozen, instead of 2S. 6d., will pay for itself many times over in making poor watches go well.

Unequal Rates.—Some watches after cleaning are found to go much slower hanging up than when lying. Generally this indicates a balance out of poise, or a hairspring not true in the centre. In very small ladies' horizontal watches this fault is often troublesome, and may be sometimes cured by deepening the cylinder depth, i.e. setting the cylinder closer to the 'scape wheel. In these very small and cheap watches side play of pivots causes great inequality of action.



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Watches - Conversions And Alterations In Movements
Amazing articles on just about every subject...


Watches - Conversions And Alterations In Movements

( Originally Published 1918 )



A VERGE with a good frame, good train wheels, and a sound case often pays to convert to a lever. An English cylinder or duplex, when the escapement has become worn, may be so altered. A pocket chronometer that has become badly damaged in the escapement will often cost many pounds to restore, and still be no better and not so strong as if converted to a lever at a quarter of the cost.

Making the New Escapement.—These are all cases in which conversion is advisable. The task is not a formidable one, and can be undertaken by any fairly good workman. An English full-plate cylinder, duplex or chronometer, is the most easy to alter. In these cases the pallet staff may be fitted to the old scape-wheel holes and the jewelling may remain as before. A new fourth wheel of a smaller diameter may be fitted, and the new scape wheel and pinion pitched as near to a right angle as possible, like Fig. 183, in which the dotted circles show the position of the old fourth wheel and scape wheel.

Scape wheels and pallets are bought in pairs matched to each other. Levers and rollers similarly matched can also be bought, but in this case, as the pallet-holes are fixed, a lever and roller must be specially made to the depth. The distance from the pallet holes to the balance holes must be measured and divided into four parts. One-fourth should be the distance from the balance staff to the ruby pin hole in the roller; the other three parts should equal from the pallet hole in the lever to the notch. This gives a ratio of lever to roller of 3 to 1.

First, procure a rough roller, or make one from steel rod. Measure and mark the ruby pin hole. Drill it and broach it true. Ordinary flatted pins are fitted in round holes. A D-shaped, half-round pin, an oval, or a triangular pin, require holes in the roller to fit them. A round hole is first drilled; then a hard steel punch of the right shape is driven in the hole. The roller edge in front of the hole can be hammered in a little to ease the punch and flatten the front of the hole. The roller can then be hardened and tempered, and turned true and flat. It should be reduced in diameter until there is a little more steel outside the pin hole than is necessary for the passing hollow. The surplus is to be trimmed off at a later stage. The hollow can be filed.

To make the lever, take a strip of lever steel and cut off a short length. Drill the centre hole, and measure and mark the position of the notch. Drill a hole there and file into it, slanting on each side to form the "horns," as in Fig 184. With a slitting file cut the notch, and open its sides true and square with a notch " side file."

Fit a brass pin in the roller and put roller and lever in the depth tool on turning arbors. Set the tool to the depth from the pivot holes in the plate. Open out the notch to depth and width. Mark and drill the guard pin hole as small as possible, and close to the bottom of the notch.

The pallet staff can be turned and fitted to the pallets and pivoted, the balance staff made, the balance mounted, the scape pinion turned and pivoted, and the wheel mounted, colleting it with gold, as this metal will enable a good rivet to be burnished on it. Broach out the centre hole of the lever to go tightly on the pallet staff up to the pallets. It is important that it should be quite tight. Put the pallets and scape wheel in the depth tool and adjust to depth accurately, leaving it just the least shade too deep. Strike this circle from the pallet hole as a centre. Put the scape pinion and fourth wheel in the depth tool, and strike another circle from the fourth wheel hole as a centre. The intersection of these circles marks the point for the top scape pivot. Drill the pivot hole, upright it in the mandrel, and mark and drill the bottom hole. Run in the scape wheel. Then put in the lever and pallets, scape wheel, and balance. Turn the lever round upon the pallet staff until it is " in angle." That is, the teeth must " drop " on the pallets at equal distances on each side of the line of centres. If the roller edge is trimmed down by trial, until when a tooth drops the guard pin just touches its edge, there will be no difficulty in getting the escapement in angle. When correct, drill the lever and pallets and pin them together. This done, the lever may be shaped up, hardened and tempered, its flats and edges polished, and the notch opened out to fit the ruby pin and polished inside. The roller can be polished on flats and edges. The flat can be done overhand on a brass polishing block. The edges may be polished in the lathe or turns. An escapement maker would use swing tools for this polishing, but the average repairer does not possess these, and would not have sufficient practice to use them properly.

The scape depth must be carefully tried to see how deep it locks, and the wheel topped in the turns until it locks as lightly as possible.

This depth is a very important one, and a minute error in drilling the pivot holes or in the registering of the depth tool is fatal to it. This is why it is advisable to pitch it just a shade deep, as the wheel can be topped to shallow it as required. Most depth tools have an error ; that is, the outside points do not accurately register the same as the inside centres. A good plan with a faulty depth tool is to reverse the runners with the points inside, and score the plate with the points in that position.

To mark the points for the banking pins, put the balance-staff and roller in, lay the lever on the top plate with the pallet-staff pivot in the top hole, and with the guard pin on either side of the roller mark just at the lever edge. Drill them a little closer than marked, and trim down the lever edges until the bankings are correct. Do not forget to poise the lever.

Three-quarter-plate Watches.—A 3/4 plate duplex or chronometer generally requires a new scape cock, as the old one is seldom the right size and shape to take the wheel and pallets. In these the new scape pinion can be run in the same holes as before, or the old pinion can sometimes be used again. If a very small wheel and pallets are used, a right-angled escapement can be made, though sometimes this is not possible. In such a case the lever has to be " dog leg," like Fig. 185, to accommodate the pins. For 4 plates a lever and roller to match may be bought, and the position of the pallet holes arranged to suit them ; or they may be made as before described. The arrangement of such a conversion is like Fig. 186, the dotted circle showing the old scape wheel.

In converting chronometers, duplex and cylinder watches, new fourth wheels, where required, and new scape pinions may be of the same numbers as before. Then the hairsprings will be used again, together with the balances, just as they are. But if such a watch has a plain balance, it will be much the best to put on a new compensation balance, if there is room for it. In this case it will need re-springing as well.

Converting Verges.—Verge conversions are rather more trouble. Some verge trains are so arranged that the third pinion can be left alone and the escapement planted quite free of it. But the ]majority require a platform made to go over the third wheel, like a bridge, and carry the escapement. The third pinion then must be cut down very short and its top pivot run in the bridge. The fourth pinion comes through a hole in it. The arrangement is shown in Fig. 187. The old potance can be generally filed and turned out to take the roller and allow the lever to reach it. If not, and a new potance has to be made, the entire escapement may as well be included in it, and the top third pivot run in its under side, as in Fig. 188 ; or the bridge shown in Fig. 187 may be extended to take the lower balance pivot as well. In converting a verge, a new fourth wheel and scape pinion will have to be supplied, and the numbers must be such as to make the train as near to 16,200 as possible. They can be calculated according to the directions given on p. 133.

An old "club roller" or "rack lever" is easily converted by supplying a new wheel and pallets, and lever and roller, and re pitching the depth.

Keyless Conversions.—A really good f plate key-wind fusee English lever is sometimes worth converting into a key-less. The best job is made by dispensing with the fusee and fitting a going barrel, with a new top plate, fitting ordinary rocking-bar keyless work and new motion work. The movement, if sent to a movement maker, will be fitted with top plate, new barrel, and keyless work all in the rough. It will then all require finishing as in a new watch. It will want " boxing in " to the case and a new case pendant. The case-maker will do this, part. He will fill in the keyholes also.

Improving Watches.—A good watch with compensation balance and a flat spring may often with advantage be altered to a breguet. Occasionally the same balance cock will do again, but generally it will be best to make a new one and stud it on the left, fitting a proper index. The old spring, if a good one, may be turned up into a breguet, or a new best hardened and tempered one put on.

Many a good 3/4 plate English lever may be much improved and made to look many years newer by a small outlay. Top plates of the shape shown in Fig. 189 may be filed up to a nice curve, as shown by the dotted line, and a balance cock like Fig. 190, A, may be turned like B. Plates may be stoned smooth and free from scratches, and the frame re-gilt. The squares, index, etc., can be re-polished and the screws re-blued. Scratchy blue screws may be re-blued without polishing, as may hands and other blue steel parts that have partially worn bright. Brush them clean and free from finger marks, and place on the blueing slip until the blue reappears all over.

The tops of brass jewel settings get shabby, or after stoning and gilding a plate, stand up too high. In such cases stone them smooth and level as they lie in the plate, then remove and polish them upon a pewter polishing block that has been filed flat. Apply red-stuff and oil and insert a peg point in the jewel hole to rub them over the block with circular strokes.



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