Examining the Escapement
Examining the Escapement names 2 different subjects across the 6 encyclopedias on this shelf. Each is set out below.
Examining the Escapement In the examination of this escapement it must be
American Watchmaker and Jeweler (1892)
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.
Examining the Escapement Before taking the watch apart
American Watchmaker and Jeweler (1892)
Before taking the watch apart, the several actions should be examined and any fault noted. See that the balance is true, both in the round and flat; also notice the action of the balance spring and that it develops uniformly. Try the various endshakes, which should be only the amount necessary for freedom. If the sideshake at the pivots is more than what is necessary for freedom, a new jewel should be fitted or a new part made, depending upon which is at fault. Stop the balance and notice the location of the impulse and unlocking pallets. When at rest the unlocking pallet should stand near the unlocking spring with the impulse pallet near the tooth of the escape wheel, which will deliver the next succeeding impulse, but the position of none of them should be changed until the watch has been tested for isochronism and in the various positions, since they may have been thus placed to complete some of the adjustments. Notice the amount the unlocking pallet carries the detent beyond what is necessary to unlock the tooth and at the same time see that the incoming tooth strikes safely upon the impulse pallet; also the distance the pallet is forward of the tooth at the time the tooth falls upon the pallet. The extent of the drop should not exceed five degrees, and may sometimes be slightly less. The distance between the edge of the impulse roller and the two escape teeth immediately adjoining it, that is, the tooth which has just given the impulse and the one which will immediately follow it, should be just sufficient to leave the parts free and should be equally divided on each tooth. If the lights, as they are called, are not equal, it shows that the position of the locking stone is not correct and which way it should be moved to correct the fault. Excessive side shake at the pivots, especially at the balance, might cause the inequality above referred to when held in certain positions. The escape wheel must be true in the flat, noticing that none of the teeth are faulty. The heights of the rollers should be so as to engage the escape teeth and the unlocking spring. The amount of lock of the tooth upon the locking pallet should be as small as possible, leaving a sufficient margin for safety. No workman who is not thoroughly acquainted with this escapement should attempt to repair it, for, since none except a first-rate workman could expect to make one which would give satisfactory results, so, none but a workman of equal skill can expect to repair it without leaving it in an imperfect condition.
What Has Changed in the Last Century
When the American Watchmaker and Jeweler set this out in 1892, the cylinder escapement was still ordinary trade work — something a jobbing watchmaker met daily, and might have to replace by turning a new cylinder from steel wire on his own lathe. The cylinder escapement was already being displaced by the lever escapement in better watches, and it disappeared from new production in the early twentieth century; the detached lever became effectively universal in mechanical watches. Then Seiko's Astron of December 1969 opened the quartz era, and by the 1980s the great majority of watches sold kept time by a vibrating quartz crystal with no escapement at all. Turning a replacement cylinder is now a specialist restoration skill rather than a bench routine, and the mechanical watch survives mainly as a luxury object.
Written for this edition, 2026.