Many of the remarks made in speaking of the Geneva movement are equally applicable to that of English construction. It will be well, however, to supplement them by a few special directions. The following points require attention. See that the position of dial is not altered by closing down the bezel; that the fusee dust-cap does not touch the dome or cap; and that the diamond endstone or other jewelling of the balance cock is free of the case. In 3/4-plate watches the chain is occasionally found to rub against the edge of the case, or the top plate to press against the bottom edge of the same, causing the train to bind. See that the balance and chain, and the fusee great wheel, are free of the cap where one exists: the chain is especially liable to rub after the breaking of a strong spring, which may cause the barrel to bulge, when it may also rub against the potence. Ascertain that none of the dial-plate feet or pins touch the train; that the hour wheel is clear of the third and fourth wheel bar; and the minute wheel out of contact with the dial plate, and not pressed by the dial.
See that the third wheel is free in its hollow; and that the balance, more especially in oversprung watches, is clear of the barrel.
The index or regulator must be tested, especially in watches that are undersprung, at several points between "fast" and "slow," to see that it nowhere approaches too near the spring, is held with sufficient firmness, and that it never comes near enough to the guard pin for contact to occur. See that the potence screw and steady-pins do not project, and that the barrel does not touch the name plate, balance cock, top plate hollowing or great wheel. Before taking off the top plate, notice the position of the detent in the steel wheel, and the amount of its end-shake; the wear of the holes, and freedom of the train wheels; the position of the third pinion with respect to the centre wheel, and that of the escape wheel to the lever. See that the banking pins are not loose or bent; that the guard pin, which protects the balance staff when the chain breaks, is near enough to the barrel and the potence. When the watch is taken to pieces, any loose pillars or joints must be secured, pivots examined to see whether worn or bent, and those working on endstones that they come through the holes.
The fourth-wheel pinion must be free in the hollow of the pillar plate and the centre wheel in its hollow; a similar examination also must be made of the collet and pin which secure the great wheel to the fusee. If a chain is broken near the barrel end, the stopwork is probably defective or the spring too strong.
The following faults may occur in English stopwork. The stop may come opposite the fusee snail too soon or too late, allowing one turn too few or too many of the fusee; or the back of the snail may butt against the stop, and thus stop the watch after going for a few hours. Overwinding sometimes occurs in consequence of the stop spring being locked between the shoulder of the stop and its brass stud; and the blade of the snail or the end of the stop may be worn or bent in cleaning. In 3/4-plate fusee watches, see that the balance does not come too near to the fusee, fourth wheel, centre wheel, and sometimes the escape wheel. The breaking of a mainspring sometimes strains certain teeth of the great wheel.
In examining a lever escapement, the following particulars should always be attended to. See that ruby pin and pallet stones are firmly set; that neither pallet nor roller is loose on its staff; and that the lever and pallets are rigidly fixed together. The guard pin must be firm, the balance well riveted to its collet, the spring collet sufficiently tight, and the curb pins firm. If there is a compensation balance, ascertain that each screw is tight.
So great a variety of arrangements of the mechanism for winding watches at the pendant is met with at the present day, that it would be impossible to give detailed directions in regard to their examination; the following general remarks, however, will be found of value in directing attention to the points which most require it, and will suffice for any intelligent workman. It should be observed at the outset, that the adjustment of keyless work is almost entirely a question of depths, and the workman who has thoroughly mastered this subject will rarely experience any difficulty in dealing with keyless mechanism. Carefully observe each depth, etc, in succession, to make sure that no prejudicial friction occurs either between teeth or by contiguous parts coming in contact. All springs should act solely in the direction in which pressure is required of them.
Special attention should be given to the intermediate steel wheel for communicating motion to the cannon pinion, when this exists, as it is permanently in gear with the train, so that any un-evenness of the depth will affect the rate: if the minute wheel hare too much end-shake or play on its stud, it is apt to ride on the intermediate steel wheel. The friction of the cannon pinion on the set-hands arbor must not be excessive, since it would involve too great a strain on the teeth of the minute wheel; nor too slight, since the hands would be liable to be displaced on releasing the set-hands stud. If the intermediate wheel has too much end-shake, limit this by an excentric screw overlapping its edge. Test the spring of the set-hands stud, to see that it is not too strong or too weak, and that it moves parallel with the plate. Failure in this latter particular might lead to its rising on to the rocking bar or other piece on which it acts.
Examine the winding-pinion depth, to see that it is neither too deep nor shallow. The set-hands stud spring must be strong enough to resist any accidental pressure on the stud; but, on the other hand, the strength must not be excessive, as the spring will then be all the more liable to break, besides causing inconvenience when setting the hands. The course of the spring should be banked at the point which gives a good depth between the winding and intermediate wheels. The minute-wheel stud must be firm in the plate, as any accidental binding might otherwise unscrew it, occasioning the breakage of the dial. When the minute hand is carried by the set-hands arbor, and not by the cannon pinion, care is necessary in fitting this latter, for if too loose it will rotate in setting the hands without carrying the minute hand round, and the minute and hour hand will cease to agree.
Attention must be paid to the application of oil to keyless work, as, in its absence, rust rapidly forms, and the mechanism becomes bound. Of course, all bearing surfaces, such as the interior of the pendant, intermediate and minute wheel studs, studs or screws of the rocking bar or other surfaces on which wheels rotate, must be lubricated; an equally important point is to liberally oil the teeth of the winding pinion and the bevel or crown wheel that engages with it. The application of a little oil inside and outside the cannon pinion must not be omitted.
Several watchmakers have noticed that the oil is preserved intact longer after washing with soap, if well done, than after cleaning with benzines, etc, though in some instances it may be that the latter process was not properly performed. However, the following is the method adopted for some years by Ber-trand: - Dissolve in about 1 qt. of rainwater a piece of Marseilles soap, about 1 1/2 in. square, pared very fine, and add a piece of black soap the size of a hazelnut. Boil, filter through a linen rag, and bottle the liquid. When required for use, pour a little into a capsule, and place the parts (excepting those fixed with lac) in it, boil it slightly, and after having put back the liquid in the bottle, pass the parts through rainwater, slightly boiling, and then plunge them in alcohol. On taking them out, dry them with a linen rag. By this means the pieces are much better cleaned than they would be if benzines were used. Should the polished wheels turn a little brown, the colour may easily be made to disappear by passing lightly over the stained portion, and without touching the steel, a pencil-brush dipped in water mixed with potash oxalate (commonly called salts of sorrel), and dipping in water and alcohol.