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Examining the Escapement (Examination of this escapement)

In the examination of this escapement it must be remembered that it is as necessary that it be put in good condition and the same care be given to the work as in the better grades of watches. This point is of importance and seems to be the cause of much trouble which might otherwise be avoided, for it must be remembered that there is a certain limit in the care necessary to ensure a good performance, below which the work will be so poor that the watch will refuse to keep time. When first looking at the watch the general appearance should be taken into account and also the motion of the balance. The balance should be true in the round and flat, also the balance spring the same condition should exist. The beat can be best tested by listening to the watch while running. If the cylinder is properly set relative to the balance the center of the impulse opening will be in a line with the small banking pin inserted in the rim of the balance and if in beat this banking pin should stand in a line with the balance center and the escape wheel center. The correction of the beat is made by shifting the balance spring around in the opposite direction to what the balance would have to be moved to correct it. The endshakes should not be excessive. Try the action of the teeth and the cylinder by slowly revolving the balance, noticing if the tooth drops upon the locking surface or upon the rounded impulse edge of the cylinder, which would most probably be indicated by a sluggish, jerky motion of the balance. Too shallow lock or no lock, may be caused by too shallow depthing or the cylinder running untrue, but in either case the remedy is obvious. The teeth should have the same amount of drop when they escape from either edge of the cylinder. The tops of the escape teeth must not touch the top of the cylinder when held in any position and it must be seen to that the arms which support the escape teeth do not strike on the cylinder either on the bottom or at the top of the passage cut out to free them. This last fault may be caused by there being too much endshake either in the balance or escape wheel or it being unequal between them. If the banking pin is properly placed and adjusted there will be no danger of over-banking. The pin in the balance cock, against which the banking pin strikes, should be bent in towards the balance center until the banking pin will strike it, but the balance will be free to vibrate. If the matching of the escapement is not correct it may be corrected by loosening the chariot screw and moving it in the direction indicated.

Making a New Cylinder. The first requisite in making a new cylinder is to get the measurements, such as the inner and outer diameter, total length and height of openings. The outer diameter is equal to the distance between the heel and the point of a tooth, allowing a sufficient amount for freedom of action. When turning out the cylinder in the rough it must be remembered that it will be necessary to allow enough metal to make up for that which will be removed in the finishing process. The inner diameter when finished is equal to the length of a tooth, plus clearance. The total length is found by removing the cap jewels and measuring from outside to outside of the hole jewels with a douzieme or other gauge. The cylinder proper must be enough shorter than the total length to allow for the length of the pivots. Heights of the openings may be measured by such a gauge as is used when replacing a cylinder or in the absence of a gauge a piece of brass may be used, filing notches into it at the necessary heights. Having the several measurements, the next step will be to select a piece of superior quality of steel wire and aneal it thoroughly. A wire chuck is now selected which fits the wire when if is mounted in the lathe preparatory to drilling the hole, which should be first carefully centered, then drilled with a cylindrical drill, which will leave the hole true and smooth. The drilled hole should be somewhat smaller than the length of a tooth to allow for the final smoothing and polishing. After the hole is drilled, and without removing it from the lathe the body of the cylinder is to be turned down until it will almost go between the points of two teeth which must be reduced in the finishing until it will freely enter between the teeth. After the outside is smoothed by using oilstone powder on a bell metal slip, the cylinder may be cut off to length and the inside smoothed by using the oilstone on a piece of wire, but if a well made cylindrical drill was used, there will be but little need of this operation until the final smoothing and polishing.

The cylinder is now to be placed upon a piece of brass wire, fitting it closely and cemented to prevent it from turning around when cutting the passage. If the workman has a milling attachment for his lathe, this may be easily done by using a cutter of the right size, but if no attachment is at hand, it will be necessary to use small files afterwards smoothing by using oilstone powder and oil on bell metal or soft iron slips. After rounding the lips it may be hardened, being careful that the steel is not burned. If only one cylinder is to be hardened at a time, which will most usually be the case, an easy fitting piece of wire may be inserted which will equalize the heating and to some extent prevent burning of the steel. Oil should be used instead of water for the hardening, which will make the steel somewhat tougher. The portion of the cylinder which is subjected to the action of the teeth should be left full hard while the other portions are to be drawn to a blue. This drawing of the temper may be best done by fitting two pieces of wire which project from each end about half or three-quarters of an inch, but do not pass entirely through the cylinder and by holding the portion to be left hard in a pair of pliers the other parts may be tempered. The final smoothing and polishing may now be done, especial attention being paid to finishing the acting portions.

When drawing the temper of the cylinder, care is necessary to prevent the impulse portion from being softened, which would cause it to wear readily. The difficulty of readily seeing if all the parts are free of each other, makes it necessary that rather more care be exercised than when examining the lever escapement. There seems to be an inclination among some workmen to slight the cylinder watch when repairing it. The old saying that "what is worth doing at all is worth doing well," should always be kept in mind by the workman, for no machine, much less a watch, will perform satisfactorily unless given due care. An escape wheel when damaged is best replaced with a new one if a suitable one is at hand, otherwise one or more teeth can be replaced if carefully done, so as to give as good results as if a new wheel was used. To do this, first with a thin iron slip and oilstone powder make a thin groove in that portion of the web from which the tooth is broken, parallel with the flat of the wheel, and about half the thickness of the web in depth. Then take from an old wheel a tooth corresponding in size and shape to those of the wheel to be repaired, cutting through the web so that the pillar and that portion of the web extending back from the tooth are still attached.

Now with the oilstone slip, carefully shape the section of the web left attached to the tooth so that it will fit in the groove cut in the wheel, and at the same time make it as thin as possible without too much impairing its strength.

The portion that fits in the groove is now to be "tinned," that is, covered with a thin coat of soft solder, which is best done by melting the solder on the end of a flattened piece of brass or coppor wire and applying while hot, having, of course, put a little soldering fluid (chloride of zinc) where the solder is to flow. Only enough solder should be used to cover that part that is in contact with the wheel. A little soldering fluid is now put in the groove and the tooth placed in position, being very careful that the point and heel of the new tooth are on precisely the same circle with the other teeth, and that there is the same distance between its point and the heel of the next succeeding tooth as exists between all the teeth of the wheel.