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Watch Repair - Keyless Work

( Originally Published 1918 )

KEYLESS watches, although very old, have only of late years become general. Comparatively few key-wind watches are made to-day, and fewer will be in the future.

The principle of all is that a milled "button" on the case pendant is connected with steel winding wheels, and winds the watch. Turning the button forward winds, turning it back does nothing, but it gathers ready for the next forward wind.

Fe hand-setting arrangement differs very much. In most English watches, to set the hands, there is a " side push" to push in with the finger-nail. This throws the winding wheels out of gear and allows the hands to be set by the button. In " lever-set" watches, the bezel has to be opened and a lever pulled out to set the hands. In " pendant-set " watches, pulling the button smartly outwards throws it into gear with the hand-setting wheels. These are the principal methods, but variations, of them are often found.

Rocking-bar Keyless Work.—Fig. 174 shows the " rocking-bar" keyless mechanism, as used in nearly all English, most American, and many Swiss watches. It is one of the simplest and most reliable.

The button is fixed on the outer end of a steel winding stem that runs in the case pendant. On the inner end of the stem there is a crown-shaped pinion, A, which drives the centre wheel of the rocking bar B. B drives both C and D. When driven forward C turns the ratchet E, which winds the mainspring up. When turned back to "gather," C slips past E, making a clicking noise. To set the hands, the side push F is pushed in. This moves the rocking bar bodily, the wheel C is lifted clear of the ratchet E, and D is thrown into gear with the minute wheel of the motion work, or with a small intermediate wheel, G, which runs on a stud free.

The rocking bar is sometimes made " lever set " by adding the lever H (Fig. 174). To set the hands, the outer end of H is pulled out and the inner end forces the rocking bar down, causing it to gear with the hand work.

In sonie watches the pinion A (Fig. 174) is fixed on a steel shaft running in bearings on the watch plate itself, and The button outside is fixed upon a key pipe which fits on the prolonged square arbor of the pinion A. In taking such a watch out of its case, a small set screw in the case pendant has to be removed, and the button and key pulled out; while in the pattern shown in Fig. 174 the button and winding pinion remain in the case, and the watch movement can be pushed straight out.

Rocking-bar keyless work has not many faults, but from wear and tear requires occasional repair. The button and winding stem sometimes run dry in the case, and stick, rust, or squeak. The button is sometimes screwed on to the stem, in which case, to remove it, hold the pinion A with pliers and unscrew the button with the fingers. More often the button is nutted on outside by a small gold nut sunk in its end. Hold the button in the fingers and turn the nut off with a screw-driver shaped like Fig. 175. Take out the stem and clean it ; peg out the hole in the case, oil it well, and replace, making sure that the button is quite tight. It generally fits on its square best in one position, and that is marked by a file mark or dot on the square and a mark on the pipe of the button.

A rocking bar that rises from the plate and allows the winding pinion depth to get too shallow can be tightened up by reducing the under side of the central steel boss of the wheel B (Fig. 174). This is of hard steel, and can only be reduced by laying it upon cork and using an emery stick, about No. 2. If the steel piece has steady pins this cannot be done, but the plate must be sunk a trifle by putting in the mandrel and taking a thin smooth facing cut across for the diameter of the steel only. The centre screw of a rocking bar, when there are no steady pins, has a left-hand thread.

If the teeth of the wheel C (Fig. 174) butt against the points of E, it shows that the click is not exactly in the right place. The click should be so placed that the wheel E presents one tooth to the wheel C. If two teeth are level C will butt. The remedy is to shorten the point of the click so that one tooth only faces C.

Broken, teeth in rocking-bar wheels cannot be repaired, but must have new wheels. These are bought in the rough, and will require thinning by filing or turning, hardening, tempering blue, and the centres turning out to fit, in a step chuck, and recessing for the shoulder screws.

If there is an intermediate wheel between the rocking bar and the minute wheel, like G, Fig. 174, it must run quite free upon its stud. The stud is often a shoulder screw, and some-times tightens the wheel up. If so, hold the screw by its tap in a split chuck and turn the head flange back a little with a thin graver point. This also applies to the wheels C and D on the rocking bar.

If a rocking bar is too tight, the centre steel piece of the wheel B may have a tissue-paper washer screwed between the plate and itself.

A brass minute wheel often gets its teeth broken through the pressure of setting the hands. They can be put in by slitting and soldering as before described, but are not very strong. The best remedy is a new steel minute wheel.

A rocking-bar watch sometimes winds badly because the depth between C and E is too deep. Like all depths, this one must have a little shake between the teeth. It is regulated variously in different watches ; sometimes the bar, or a stud in it, banks on the plate, and the plate must be punched a little ; or by a screw head, in which case a larger screw can be fitted.

Shifting - sleeve Keyless Work.—" Shifting-sleeve " keyless work is on a different principle altogether. The diagrams (Fig. 176) show the upper and lower views of a typical Swiss watch with this kind of winding work. The button and winding stem pass right into the watch. The stem is squared, and carries a crown wheel or shifting sleeve, B. B can move upon the square stem by an easy sliding motion, but is bound to turn with it. A is the winding pinion, and rides loose upon the stem. It gears with the winding wheel G on the top plate, which in turn winds the spring by means of the ratchet wheel H. The pinion A has on its side or face next B a set of ratchet teeth engaging with a similar set on B. The spring E keeps B up against A. When the button is turned forward it carries B round. B carries A, and the spring is wound. When the button is turned backwards B slips past A, the spring E forming a click spring, and the result is only a gathering action. The side push F forces the spring E inwards, and carries the shifting sleeve B down to gear with C and D to set the hands, instead of driving A.

When well made, this is a very reliable form of winding work; but many of the watches to which it is applied are of the cheapest, and the workmanship is bad. The wheels A and B are liable to get the teeth worn or broken. They can be bought ready made in a finished condition. The spring E is liable to breakage. Rough ones can be sometimes bought, but they vary so much in shape and size that there is frequently no other way than to file up a new one from sheet steel and make it throughout. This job does not require any special instructions, as the old one or its parts are available for measurement. First drill the screw hole, and work from that as a fixed point. When roughed out, harden and temper it. Then finish down to size.

The depth between the pinion A and the wheel G is often faulty, generally shallow. When G is an ordinary wheel with one set of teeth, it can be deepened by getting A forward. This can be done by putting a very thin brass or steel washer behind A. When G has a double set of teeth, G must be got bodily down. If it merely has too much play, reduce the under side of its centre steel boss. But sometimes it must be sunk by turning the plate or bar in a mandrel. This keyless work wants plenty of oil on the winding stem and the ratchet teeth of A and B.

A new winding stem is easily made in a lathe. A piece of hardened and tempered rod is held in a split chuck, and the entire job done at one chucking, all except the squaring to fit B. Let it be finished smooth; polish the end pivot and the shoulder where A turns. The buttons are sometimes driven on to a squared end, sometimes screwed on, and occasionally held by a small side set screw.

The centre screw holding G has usually a left-hand thread.

Variations of this form of keyless work are found in American and a few English watches. In some the winding wheel G is not on the top plate, but under the dial, being screwed to a steel platform covering B and A. A lever-set arrangement may be fitted to it as to a rocking bar.

Pendant-set Arrangements.—The most important of these variations is, perhaps, the pendant-set arrangement adopted in many Swiss and American watches. Fig. 177 shows the arrangement adopted by Messrs. Patek Phillippe & Co., of Geneva, which is a typical one.

The winding stem has a fixed flange, F, upon it, which comes just against A. A and B are of the same shape, as in Fig. 176. B is kept up to A by the spring H. G is another and stiffer spring, which in its normal position lies as in the figure. This watch winds exactly as described before ; but to set the hands the button is pulled outwards. The flange F acts on the steel piece E, which draws the pinion A, and keeps it against F. E also forces G downwards, and G carries B down with it into gear with C and D, the motion wheels.

These watches of Patek Phillippe unfortunately require taking partially to pieces to get them out of their cases; but the keyless work is well made and very reliable. By varying the arrangement a little, as in " Omega" lever watches and some others, including some patterns of Walthams, the flange F, Fig. 177, is dispensed with, and a separate piece, A, Figs. 178 and 179, added, operated by a slot or groove in the winding stem. This enables the watch to be got out of its case more easily, as by loosening the screw holding the separate piece it is liberated from the groove in the winding stem, and the latter can be drawn out. Figs. 178 and 179 show two forms of this kind.

The separate parts of this keyless work, winding stem, springs,. etc., have to be filed up and made by the workman if they want replacing. But the wheels can be bought finished in most cases.

Some American pendant-set watches are very complicated, and have many curiously shaped springs difficult to make. Fortunately, they can be purchased from the English agents of the manufacturers. The idea of American manufacturers is to produce a watch which shall be interchangeable with any standard case. The form of pendant-set keyless work above described does not lend itself to this very well. Hence their efforts have been directed to devising a mechanism that shall be all contained in the watch, and not depend on the winding stem or case. The idea has generally been carried out by making the winding stem hollow like a tube, and letting it lie in bearings in the watch plate. Pulling the button outwards allows a central shaft in the hollow stem to slide up, and by an arrangement of levers and springs, slides B into gear with the motion work. In their later watches these systems have been abandoned for simpler mechanism more resembling Fig. 177.

In these and many other keyless watches slender steel springs like fine wire, hardened and tempered, are often used. They frequently break, and sometimes are lost. Often they are troublesome to make, and in many cases springs answering the purpose can be quickly made from fine brass wire, hammered stiff and bent up to shape. Such brass springs generally act as well as the original steel ones, and are less liable to break.

Winding Wheels.—Keyless winding wheels require great strength, especially in the teeth. Most have round-bottomed short teeth, like Fig. 180), at A. The square angles at the bottom of an ordinary tooth offer invitations to break under pressure. These teeth are very much stronger. Teeth of this shape are also used for barrels and main wheels in the going train in good watches. The teeth shown at B, cam-shaped, are also used in many Geneva winding wheels. Teeth like these only permit of running in one direction, and in keyless work that is all that is necessary.

The forms of keyless work shown here are the usual ones met with ; but there are a few others occasionally seen, especially in hand-made English watches. Although differing in arrangement, they will present no special difficulty to the repairer.

Fusee Keyless Work.—All these different kinds of key-less work are applicable only to going-barrel watches. Fusee watches, if required to be keyless, present a difficulty.

In the first-mentioned class----the going-barrel watch—the barrel arbor stands still while the watoh goes, and only moves when turned by the keyless work in the act of winding. This simplifies matters, as the winding work can always be in gear with the barrel arbor. In the fusee watch the fusee square is always slowly turning round while the watch is going, and there-fore the winding work and button must be free and disconnected from the fusee, except while winding. If not, the whole keyless work would revolve while the watch was going, and the button would catch in the pocket and stop the watch.

In the rocking-bar watch it has been seen that the ratchet must present one tooth to the winding wheel, or butting of the teeth will result. But a wheel on the fusee arbor is liable to be in any position at the moment of winding, and therefore nearly all fusee keyless watches butt badly as they are wound. In some there is a kind of rocking bar, which normally is disconnected with the winding and hand work. To wind, a push is held in, throwing the rocking bar into gear with the fusee wheel. To set hands, another push is needed. Or one push may be made to answer both purposes by being pushed in to set hands, and let out (by opening the case back) to wind. Others wind to the left, and throw into gear automatically with a sliding motion of the rocking bar, and set hands with a side push. A few wind with a circular gathering click working round a ratchet, throwing itself into gear when pressed forward. These automatic arrangements all have an uncertain loose feel in winding, and waste much power; while the positive action ones (by opening case, side push, etc.) are more or less a nuisance, and butt badly as well.

Altogether, fusee keyless watches are unsatisfactory and troublesome, not one in twenty winding even passably.

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