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Repeating Watches, Etc.

( Originally Published 1918 )

REPEATING watches strike the hour, quarter, 'etc., last indicated by the hands, upon pressing the pendant or pulling a slide. Small steel hammers strike circular wire gongs arranged round the movement just inside the case. There are generally two gongs fixed on one base, or it may be on separate bases. Fig. 194 shows a Swiss repeater movement in which the hammers and gongs can be seen in position.

Quarter repeaters strike the hour on one gong and the quarters on two gongs, known as ting-tang quarters. Half-quarter repeaters, in addition, strike one on the second gong after the 'quarters, if the half quarter has passed. Minute repeaters strike the hour on the first gong, ting-tang quarters on both, and the minutes on the second gong. Five-minute repeaters strike the hour on the first gong, and the number of five minutes past the hour, up to eleven, on the second gong.

Clock watches strike the hours and quarters like a quarter-chiming clock as they come round, constantly reminding the wearer of the time. In addition, they will repeat like a minute repeater when required.

Repeating Mechanism.—Repeating watches contain a second small mainspring to do the striking. The act of pushing in the pendant or pulling the slide winds the spring up a little. In running down it operates the hammers, through racks with saw-shaped teeth, and is regulated by a small train of running wheels and a fly pinion, or an anchor escapement like an alarm clock, to prevent it running too fast.

Hour-striking Work.—Fig. 195 shows a repeater hammer. A, A are its pivots upon which it turns ; B is a steel stud that passes through a slot in the plate and by which the hammer is operated.

Fig. 196 shows the under side of the watch plate. The pivot A comes through a pivot hole and stands up; B comes through a slot; C is the hour rack mounted on the squared arbor of the main wheel of the repeating train; D is the hour hammer pallet; C is wound up by the toothed rack E. In old repeaters E is pushed down by a slide in the pendant, as in Fig. 200. In modern ones E is operated by a slide at the case edge. In some old watches C is wound by a chain passing around it and pulled by a lever operated by a pendant push.

When C is wound up by any of these methods, the teeth pass the point of the pallet D, which trips backwards as the teeth run past it, being returned to its proper position by the light spring F. As soon as it is released, C commences to run forward and the teeth operate on the point of the pallet D, each tooth causing one blow of the hammer upon the gong. The number of blows is thus regulated by the number of teeth of C that pass the pallet. This is determined by the distance to which the rack E can be pushed down. It is pushed down until its lower point G rests upon a step of the hour snail H, and it can be pushed no further. The hour snail is of the same pattern as in clocks, and is mounted upon a " star wheel," J, of twelve teeth, held in position by the jumper K and spring L. It is turned one division each hour by a projecting finger upon the cannon pinion.

Thus, as far as repeating the hours goes, the action is simple. A slide is pushed outside the case ; it drives the rack E (Fig. 196) down until its lower point rests upon the snail H. This turns C (Fig. 196) round, a certain number of its teeth passing the pallet D. When released, C returns under the influence of the repeating mainspring, and each tooth causes one blow of the hammer. In Fig. 19G the rack E rests on the ten o'clock step of the snail H, and ten teeth of C have passed the pallet D.

Quarter-striking Work: The striking of the quarters is done by a quarter rack, P, Fig. 197. This has a double set of three teeth, which act alternately on two pallets, R and S, one on each hammer axis.

The pallets R, S, are provided with returning springs, which hold them in position and allow the rack teeth to trip by them as the rack falls. A finger, Q, is mounted upon the squared arbor of the repeating main wheel, and, as soon as the last hour is struck, gathers up the rack P and causes its teeth to act upon the pallets R and S, striking three ting-tang quarters. The distance to which the rack P can fall is regulated by its tail, U, coming into contact with the quarter snail T, which is mounted upon the cannon pinion. The parts shown in Fig. 197 are above and overlay the parts shown in Fig. '196.

Minute Repeating Work.—A minute repeater has, in addition to the quarter rack P (Fig. 197), a minute rack above it, working upon the same stud as a fixed centre. It has four-teen teeth, which actuate a second pallet above the pallet S. Its tail falls upon the minute snail M, Fig. 198, also upon the cannon pinion just above the quarter snail. The minute snail has four " wings " each with fourteen steps upon it, regulating the number of minutes to be struck.

Hammers.—The hammers of a repeater do not bank against the gongs, but are held a small distance from them by steel banking pieces (X, X, Fig. 199), which can be set to the required distance with set screws. Each hammer has its spring, which causes the blow. In Fig. 199, X, X are the banking pieces, set by the screws W, W, and V, V are the hammer springs. B, B are the hammer studs, as in Fig. 195. In most repeaters the hammer set screws come through the plate to the back of the watch, but in some old ones they go through the edge of the plate.

Action of Repeating Work.—Just at he hour there is a danger of three-quarters being struck after the hour snail has moved and the next hour has been given. To make this impossible, the quarter snail has underneath it a loose steel plate which, just as the star wheel moves, is flirted forward into such a position that when the quarter rack falls its tail is arrested.

Similarly, the minute snail has a loose plate underneath, having four arms to arrest the tail of the minute rack, so that when the next quarter is struck it will not be possible to strike fourteen minutes as well. This loose piece is flirted forward by a lever, N, Fig. 198, actuated by a slender spring, O. M is the minute snail. As the loose piece under it passes under N at each quarter of an hour N is lifted a little, and when the edge of the loose piece passes under the point of N it is suddenly flirted or jumped forward.

The quarter and minute racks each have their springs, which, as soon as the racks are released, cause them to fall upon their respective snails. The racks, when arranged as in Fig. 196, are held up by a curved steel spring running round the edge of the movement, called the " all or nothing" piece. Until this piece is lifted nothing can be struck. It is lifted by a small lever just at the moment the rack E (Fig. 196) is driven home against the snail. The exact way this is arranged differs in almost each watch, but its working can be easily seen by inspection. In some E has a loose piece, G, under it, which comes into contact with the snail and lifts the " all or nothing" piece. In others the snail is mounted upon a lever, F, Fig. 200, having a slight movement, and this lever is pressed down when E is driven home, liberating the racks.

Different makes of repeaters vary very much, but the principles of all are the same. The rack E (Fig. 196) may have an intermediate wheel, B, Fig. 200, between itself and C ; or it may be on the right or left of C. The hour rack C is in some old watches between the plates instead of under the pillar plate, in which case the hour hammer pallet is also between the plates. The hammer stops and springs may be arranged in many ways, but the action is always the same.

Fig. 200 shows an older arrangement than Fig. 196. In it a pendant push, AA, pushes down the rack E until its point, G, rests upon the snail H. H is on a movable arm pivoted at F, and having a very slight motion. This motion is sufficient to depress the point C and liberate the point D of the quarter rack P. The quarter rack then falls until its foot, U, rests on the quarter snail. When the quarter rack is gathered up, the point C of the bar F holds the quarter rack up by the point D. In this arrangement the rack E sometimes drives the hour rack pinion by an intermediate wheel, B, as shown, and sometimes by a chain passing round a pulley wheel or roller. The latter arrangement is a very old one.

Speed of Repeating.-The speed of the repeating train is regulated in old watches by a loose pinion sometimes weighted with a small disc of brass. Its top pivot runs in an eccentric brass bush, which can be turned by a screwdriver to regulate the depth. Shallowing it causes it to run faster. Deepening it makes it slower. More modern ones have a scape wheel and a small pair of weighted pallets, making an escapement which runs through rapidly as the train runs. The speed of these is regulated by limiting the travel of the pallets by a pivoted wire arm, like Fig. 201, which can be turned from the back of the watch by a screwdriver. Giving it less play quickens it.

Cleaning a Repeater.—In taking a repeater to pieces, first take off the minute and quarter racks and their springs. Push the slide a little way to wind up the repeating spring, and block the train with a wedge of tissue paper or by the curb shown in Fig. 201, so that it cannot run. This eases the pressure off the various parts. Then take off the rack E (Fig.196), the spring F, the rack C, and the pallets and their springs. The repeating train can then be allowed to run down. Take off the snails and all other parts, being careful to keep all screws with their respective parts, so as not to get mixed.

Clean all as usual. In putting together, first put in the repeating train, the spring barrel, and the hammers, etc. Then the going train and barrel, escapement, etc., being careful to apply oil to pivots as you go on, as many of them will be covered up by other parts. It is then as well to put the movement in its case, and lay on its back to put on the repeating motion work.

Next oil all the underneath pivot holes. Put on the hour rack C (Fig. 196), the pallets, hammer springs, pallet springs, snail and star wheel and their springs. The square upon which C goes has a dot or a file mark on one side. Let the solid part of the centre pinion of C go next this mark. Block the repeating train. Place a small key upon the square above C, and wind it up about two turns, letting the teeth of C pass the pallet until the last tooth has just passed and the watch would repeat twelve. Then put on the rack E in such a position that it rests upon the twelve o'clock step of the hour snail. The repeating train may now be allowed to run. Put on the quarter and minute racks, their springs, etc., and the finger Q (Fig.197), pinning it on. Then the " all or nothing piece," and the quarter and minute snails, etc.

The hammer pivots require oil, and their studs where the pallets press them, also the hammer spring ends, the pallets where they turn on the studs and where their springs touch them, the stud upon which the racks turn, the points of contact between all springs and their racks, etc. See particularly that the loose pieces of the snails are free and left quite clean and dry, or they will stick.

In cases where there is an intermediate wheel between E and C (as in Fig. 200), the rack, the wheel, and the pinion of C are dotted to show the correct position to put together.

Handwork.—To put the hands of a minute or other repeater on at the correct time, repeat the watch before putting the dial on and note the hour, say seven. Then have a watch going on the board by its side. Watch this as the repeater hands are turned round slowly until the snail moves and changes to eight with a sharp click. Note the time by the other watch. Then put on the dial, seconds and hour hands ; put on the minute hand at as many minutes past the hour as the watch travelled since noting it. Finally, test it by holding to the ear as the hands are set and listening for the " click " of the snail moving at the hour.

If the hands of a repeater move very easily they may drag and lag behind when they come to move the hour snail. If not so easy as to drag, but still not very tight, they will, in a minute repeater, be jumped a portion of a minute forward at each quarter of an hour by the lever N (Fig. 198), causing an irregular gain of some minutes per day, which is apt to be very puzzling.

Old Repeaters.—Some old repeaters have the going and repeating trains all between the same plates, and are sometimes awkward to get together. An extremely thin steel hook for pulling and pushing purposes is then useful to get some pivots in. More modern ones are better arranged.

If the repeating train runs much too fast and cannot be regulated, let down the spring a turn or so. Most modern ones have a loose barrel held by a small click. Older ones have to be partly taken to pieces again to do this. If still too fast, as many old repeaters get with wear, weight the fly pinion with a heavier brass disc, a little out of centre, that is, not exactly poised.

Small Faults.—If the hammers jar on the gongs, they are too close, and must be set a little further off. If the gongs foul each other or the case, they can be bent a little, with great care, in the fingers. Sometimes the slide in the case sticks ; this is generally through dirt, and if taken out, cleaned, and oiled it will be all right.

A wide bottom centre hole is the cause of many troubles, allowing the quarter and minute snails to be loose and unsteady. Such a hole must be well bushed. Snail loose pieces that stick generally do so through having been oiled. They should be cleaned and left dry. They can be eased by slightly loosening the small collet underneath that holds all together.

In minute repeaters,. with wear, the sharp corner gets worn off, N (Fig. 198), causing the minute snail to move too late, and often allowing the minutes to be struck after the hour has changed. Also, this fault often stops the watch by allowing the minute rack to fall, when there will be no time for it to be gathered up before it is overtaken and jammed by the arm of the minute snail. The remedy is to re-point up N centrally, by careful grinding with oilstone dust on a flat steel polisher and polishing with red-stuff. Just grease the point of N very slightly. The exact time of flirting of the minute snail may be adjusted by working the point of N backward or forward by grinding the forward or backward slopes as required. If it flirts too soon, the period during which fourteen minutes are struck will be a very short one, or may be absent altogether. If too late, the rack may jam as described.

A complete failure of one hammer to strike is generally caused by its pallet sticking. See that all are perfectly free and easy, and that their recovering springs act promptly.

A failure to strike the last minute or stroke of the quarters is often caused by the slide sticking when nearly home. Dirt accumulates at the end of its slot and prevents it from going quite home.

Clock Watches are on a different system to repeaters. They have two trains and mainsprings, both wound by the same keyless work, forward winding one spring, backward winding the other. As the watch strikes continuously, they bath run down together. To repeat these watches, a slide is moved a little only. It operates a small lever inside and releases the striking train, which then runs and repeats the last hour, etc. The slide does not wind up a spring, as in a repeater, but only liberates a small catch.

Clock watches are very complicated pieces of mechanism, and look to the uninitiated a mass of springs, levers, and racks. But to a man who has thoroughly mastered minute repeating work they will present no difficulty. The great thing in cleaning them is to keep each spring with its lever or rack and all screws with their pieces ; to pin on and oil each part as it is put on, and see that all are free, and to oil all contacts of parts with their springs ; to look out for dots on wheels and racks, etc., and be careful of them ; to leave all flirting pieces dry, so that they cannot be fixed by oil. This is especially true of the mass or bundle of pinions, etc., on the squared axis of the striking wheel. There are several flirting actions there, and oil will be a fruitful cause of trouble.

There have been other forms of both repeaters and clock watches made, but by far the greater number are as here described. One form of repeater deserves some notice. It has the hour-striking teeth and the quarter teeth all on one steel wheel, and the pallets have a "rise and fall" motion, putting them into and out of gear with the teeth. A careful inspection of the parts before taking apart will be sufficient to show its action and be a guide to putting it together again.

Some very old watches—generally verges—have bells in-stead of gongs. These, of course, take up much more space, and in modern watches would not be tolerated. Others were "dumb repeaters." In these the hammers struck steel blocks in the case, causing a dull thud only, which could be felt by the hand but hardly heard at all.

Alarm 'Watches have been made which could be set to go off at any hour, much in the same way as a modern alarm clock, and generally were operated by very similar means. They will offer no special difficulties. The same remarks apply to Musical Watches, which play a tune at the hour or when required. Such watches are out of date, and the " music

generally of a poor quality. In them there is usually a stack of flat steel gongs, operated by a pin barrel like a musical box, and a train of running wheels governed by a fly pinion.

Broken Parts.—Any of these watches can be repaired by a workman who has learned to file and turn properly. Broken repeating parts may be sometimes repaired by brazing with brass spelter, re-hardening, and tempering. Some parts on which there is little strain may be soft soldered. New parts can be made by filing and turning from rough steel, being hardened, tempered, and smoothed off to shape. Teeth may be dovetailed and soft soldered in racks. The pivots upon which most parts work are steel studs screwed into the plates, or screwed into the parts themselves, and the sockets which work on the studs are also screwed into the racks, etc. Hammer arbors are screwed in to a shoulder. Hammer studs are also screwed.

A new minute hand to a repeater with a square cannon pinion is difficult to fit, on account of filing the square to exactly face the right way to correspond with the striking. Hands for these watches can be bought, with revolving sockets. When filed out to fit, the hand can be turned round on its socket until correct, and then riveted up tight.

Old English chain repeaters sometimes break their chains. In mending, new links must be supplied or made of the exact length of the old ones, or difficulties will arise and wrong numbers will be struck.

The general remarks on p. 208 apply equally to repeaters, and those not thoroughly familiar with the work are advised to study them.

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