The evolution of automatic machinery as applied to the manufacture of watches at Waltham, Mass

Front matter

A o-

I). H. CHURCH.

THE EVOLUTION

Introduction

As mankind develop in intelligence and culture, their wants become more numerous and varied and their requirements more exacting. The supply of one want but briefly anticipates the creation of a new one. which in turn demands satisfaction, so that the great and growing business of the world seems to be to supply its various wants. To a certain extent this supplv business possesses the nature of a barter, in that it is an exchange of commodities, not always a direct exchange, indeed, it seldom is so simple a matter as that, yet in an indirect way all business as such is simplv a channel through which the multitudinous wants of mankind find their supply. As the great majority of people have certain wants in common, the matter of providing an adequate supplv becomes very important, and calls for special means or agencies through which to work, so that it follows that the better the means of supplv the cheaper can be the supply obtained and the want satisfied. So that it is by no means an indication of laziness or indolence in an individual if he uses his brains in devising an easier, or b INTRODUCTION.

quicker, or cheaper, or better method of performing his work. On the contrary, it will in many or in most cases prove quite the contrary fact.

It is one of the inherent conditions of human nature, especially of physical nature, that it is susceptible to fatigue. It is also a fact that a condition of weariness is not conducive to the attainment of the highest results, either in quantity or quality of work produced. If one of the qualities demanded in any certain kind of work be the highest attainable degree of uniformity, it will be readily admitted that the individual workmen, with the certainty of constantly recurring periods of fatigue, which make imperative corresponding periods of rest, is at a great disadvantage when in competition with an impersonal and tireless machine which is capable of producing work of a like kind. The man gets tired, or nervous, or is not feeling well, or is inattentive, or careless and indifferent. The machine has no such weaknesses, and though its work is not held up to the standard quality by any domination of its own conscience, yet its mechanical functions are so invariably exercised that its product of work will surpass that of its human competitor, not alone in quantity, but in exact uniformity as well. How much better then is a man than a machine? Within certain limits the machine is the

INTRODUCTION.

better, for the reasons already stated. Still, the powers or capabilities of the machine are limited to a very narrow compass, i. e.. it can perform the particular duty for which it was made, whereas the man. the human machine, is capable of adaptation to the performance of of a great variety of duties. But within the field of its capacity the properly designed and zvell made machine will outstrip the man. Especially will this fact be apparent in the production of articles which from their nature demand the exercise of special skill and unremitting care and attention in their fabrication. Work of such nature calls for a great degree of nervous strain on the individual engaged in producing it. The expenditure of nervous energy entails fatigue, which in turn reduces the ability to exercise the needful skill or to concentrate the operator's attention, and a lessened quantity and inferior quality of product results.

If it is desired to produce large numbers of articles which shall be substantially alike, and which are composed of a variety of parts, it is evident that economy in production will be best secured by a subdivision of the labor, by which large numbers of similar parts shall be produced bv the same workman. It is also evident that if the large number of required pieces whose function is the same, can be made with dimensions exactlv uniform.

IO INTRODUCTION.

there will result a great reduction in cost of manufacture because of the avoidance of any individual or special fitting of the various parts.

Such a system of manufacture has within the last fifty years come into very general adoption in all extensive concerns, and from what has been said, it will be evident that its success must depend upon the adoption of machines, and the comparatively small amount of individual skill demanded. So far as is known to the writer, the most complete and comprehensive system of manufacturing on the interchangeable system, in its earlier years, was introduced by the United States Government for the manufacture of army muskets, at the United States Armory at Springfield, Mass. Credit for a large share of the mechanical excellence of that system, and for the invention of many of the ingenious machines then and still in use for that work, belongs to the then master mechanic at the armory, Cyrus Buckland. One of the interested students and great admirers of that ingenious mechanism in those early days was a young Boston watchmaker named Dennison. who was convinced that by the construction of suitable machines it would be not only possible but entirely practicable to manufacture the delicate mechanism of the pocket watch on the interchangeable system; and feeling that such a scheme was

INTRODUCTION. 1 1

feasible and might be made to yield a good manufacturing profit, he endeavored to establish a watch factory, to be conducted on that system of manufacturing". After years of delay he succeeded in organizing a company and in beginning the work of preparation. As his plan was to substitute machinery for skilled labor to a large degree, it was of course needful to design and build the special machines required. The field was new: experience could afford little assistance; money was by no means plentiful, and it was therefore needful to proceed with caution, so that expensive mistakes might be avoided. It was. moreover, an uncertain matter as to the magnitude of the business to be done, assuming that the new manufacturing system should prove successful. It is no detraction from the ability or the ingenuity of the original mechanics of the watch factory that they did not at that early date attempt the use of elaborate and complicated machines, such as we now have in use. Such an attempt at that time might indeed have given evidence of inventive or mechanical ability, but it would also have been an indication of poor business judgment, and would have been a waste of the little money then available. Large capital is an absolute necessity in the manufacture and employment of automatic watch machinery to any general extent, and in this branch of

12 INTRODUCTION.

business, as well as in almost all others, the larger concerns possess this great advantage over their smaller competitors.

If it were possible, it would be interesting to review the various forms of machines which have successively been used in watch making on the American svstem; which system, as has been suggested, consists in makinglarge numbers of pieces of exactly uniform dimensions, so that they may be used interchangeably. As the onlv practical means of such manufacture, the system proposed and demanded special machines for the performance of the work, not only for the sake of economy, but also to do away with necessity for special skill in the individual workman. Such a review is. however, impossible. Most of the discarded or displaced machines have been destroyed. But of those which remain we may make a brief study, sufficient we trust to note the direction and path of progress in the evolution of the more complicated and costly machines now in use.

EVOLUTION Or AUTOMATIC MACHINEPV.

Chapter I

In the review of machinery employed in watch making, it will be both natural and proper to consider, in the first place, the machines employed in the production of the plates. Of course the great bulk of the work on the plates is in the nature of turning, which involves the use of special chucks, and to a certain extent, of special lathes also. By the death of the late Ambrose Webster. the writer is deprived of an authority in certain matters of historical nature, for Mr. Webster was, during some of the early years of the Waltham factory, immediately engaged in the making of tools and machinery, and was well informed as to the origin of some of the foundation devices which have been universally adopted in American watch factories, and which by their evident value have also commended themselves to the attention of manufacturers in other lines. One of those primary devices, and perhaps the most important, is that of the " draw-in chuck. " so called from the method of its

H

EVOLUTION OF AUTOMATIC MACHINERY.

operation, it being caused to grasp the enclosed object

by being drawn into the tapering mouth of the lathe

spindle. It is also known as the ''split chuck," from

the form of its construction. Probably the oldest form

of such chuck is found in the "Aiken's awl," (Fig. i)

which is still in use in the

hollow awl handle, rilled

■^b>> 'WB with an assortment of awls

^k if- and other simple tools. This

awl handle is constructed with a sleeve or socket, the mouth of which is bevelled or tapered, and the inner end tapped with a screw thread. The chuck, at its inner end, is threaded, while its outer end is bevelled to correspond with the socket which receives it. The projecting part is made square, to fit an accompanying wrench, and the chuck being split nearly to the inner end, forms two jaws which grasp the tool as the chuck is screwed in. It is not now known whether in originally adapting this chuck to watchmaking lathes, the projecting squared portion was retained, though it is believed that it was so retained for a time, but was

Fig. i.

succeeded by a solid rod or screw which extended through the axis of the lathe spindle and was operated by some sort of wrench applied to its outer end. This form of construction naturally suggested the use of a permanent handle, i. e.. the " hand wheel " which is now in universal use. Still later the solid rod was succeeded by a hollow one. and the form of the closing chuck modified, until there was evolved the springchuck and draw-in spindle, as now used in all watchmaker's lathes. Credit for the latter stage of improvement doubtless belongs to Mr. C. S. Moseley, who introduced it while the original of the Waltham watch factory was located in Roxbury, Mass.

Without doubt the early form of this split (or spring ) chuck was used for holding wire, or small pieces of cylindrical form, but later the outer end of the chuck was enlarged, so as to hold the round discs of brass used for plates and wheels. But for holding work to be turned on its face, and which it was desired to duplicate or multiply in large numbers, and of exact and uniform thickness, the " draw-in chuck " possessed an inherent imperfection. If. in operating upon a succession of pieces, which it was desired to have of uniform thickness, one piece should be a little larger than another, the chuck could not be drawn into the taper mouth of the spindle to the extent which the smaller pieces would allow, consequently the larger pieces would be turned thinner than the smaller ones. A similar effect would be produced by unduly straining the draw-in spindle. To overcome this inherent fault, some one (probably Moseley). very ingeniously modified the construction of the lathe so that the chuck should be held stationary, as to any lengthwise motion, and the closing of the chuck be effected by the endwise movement of the outside spindle. This form of construction, although varied in some particulars, has been in almost universal use in all watch factories for about thirty years or more, and w r ill doubtless continue. This form of lathe is known as the ''three bearing," or more properly, "the slide spindle lathe." (Fig. 2.)

In 1873. Mr. C. V. Woerd designed and patented a modified form of " slide spindle lathe." which was nominally a two-bearing lathe, the third bearing being obtained by making a long telescope fit of the draw-in spindle in the rear end of the running spindle. With very nice fitting, such a lathe would run fairly well for a time, but it never was a satisfactory form of construction, and was abandoned. In the view of this lathe, as shown (Fig. 3), it will be observed that it is made to close the chuck without the use of the ''hand-wheel,"

i8

EVOLUTION OF AUTOMATIC MACHINERY.

the closing being performed by the action of a stiff spiral spring, mounted on the draw-in spindle, while the opening was done by means of a foot lever connected

Fig. j. — WoercVs Two-Bearing Slide Spindle Lathe,

with] the forked bell crank lever attached to the lathe head. While this was not the original form of self-closing lathe, (as springs had for many years been used to operatt^the draw-in spindle of small lathes for very light work ) . yet it was an advance toward a better form of self-closing lathe (Fig. 4). which has. by successive steps, reached a form of construction so useful as to be extensively employed, largely for the reason of its adaptability to automatic operation, and. from that fact, being peculiarly fitted to be incorporated in the more

Fig. 4. — Self-Closing, Three-Beating Slide Swindle Lathe.

complex forms of machinery which are made automatic throughout.

Having thus briefly sketched the growth of the chuck and the lathe, we reach the point of their joint operation in the manufacture of watch plates. It was the early method in this factory to employ the slide spindle lathe, above described, with hand wheel for closing and opening the chuck for holding the plates, in conjunction with the common form of slide rest with the two slides, each movable by screws turned by the two hands of the operator. Later the hand wheel was succeeded by the self-closing form of lathe, the opening of the chuck being performed by a combination of levers operated by foot. Then came the substitution of levers in place of the feed screws for manipulating the slide rest. Still later came an attachment to the lathe head for operating another tool, which served to round or bevel the edge of the plate after being faced by the slide rest tools.

A story is told of a young musical student who claimed that he could write a musical composition which should be correct, and yet be beyond the ability of his teacher to play. As his teacher expressed doubts as to the young student's ability in that direction, he was requested to submit his composition for trial. On laying it before his teacher for him to plav on the pianoforte, there seemed to be nothing unusually difficult, until he came to a passage which demanded the use of the two hands at near the extremities of the kevboard, while there was call for a note to be struck on one of the keys near the center. Of course the professor stopped, with the exclamation that "such a passage could not possibly be played by any one." But the youth assured the master that it was not only possible of execution, but was by no means difficult, and seating himself at the instrument, he began the composition, and when he reached the peculiar passage he bowed his head and struck the required key with his nose. In the case of this plate-turning lathe, the operator's two hands are engaged in manipulating the slide rest, and his two feet in stopping and starting the lathe, and opening the chuck. As a means of operating the cornering stool above mentioned, the knee of the operator is brought into service with perfect success.

It is obvious that a person could attend to but one lathe of the kind described, and that the watch plate would require a large succession of turnings, each of which would require a special chuck, consequently a very large number of lathes would be demanded, beside the consumption of much time in changing chucks and adjusting the tools.

Within two years, however, Mr. D. H. Church has constructed two machines for plate turning, which mark a new departure in that direction, the novelty being in their adaptation to the performance of a number of turnings, equivalent to a number of machines and operators. The first of these machines is designed for turning the recesses in pillar plates, such as are shown in the accompanying illustration (Fig. 6), which shows the train side

2 1 of a 16-size plate, with recesses turned for the barrel, the escape wheel, the pallets, the balance, and the bearing for the intermediate setting wheel, also a small recess for the center pinion. The blank plates, having been faced on both sides, and having the diameter turned, and the dial feet holes made, are placed in a tube at the left hand end of the machine, whence, they are taken, one at a time, by a swinging carrier arm, and are placed in the chuck of the first running spindle.

By the action of a cam on a shaft below and parallel with the running spindle, which is at rest, one of the slides of the compound tool carriage is moved toward the work, which carries the turning tool into operative position, and the chuck spindle being at the same time set in motion, the tool commences its work of cutting the recess, beginning at its outer edge. When the tool has cut to the proper depth, another cam comes into action, and the tool is moved across the work, turning toward the center of revolution. If a slight boss is desired at the center of

Fig 6. — Sixteen size Pillar Plate,

showing six recesses made by

Automatic Machine.

the recess, the tool is withdrawn at the proper time and distance, and when the recess is complete the turning tool is automatically drawn back and returned to its original position, which allows room for a second carrier to swing over into position to receive the recessed plate. By this time the revolution of the chuck spindle has ceased, and this second carrier moves up into contact with the plate, and as it recedes again it carries the plate with it, and swinging over, it moves up and deposits it in the chuck of the second spindle, but in such position that the succeeding recess will be made in its proper location on the watch plate. Another and suitable tool is now brought into action in a similar manner to the first, and when its work is completed it retires, and a third carrier takes the plate and places it in another chuck. In the meantime the two preceeding chucks have received new plates, and so the work progresses simultaneously, six recesess being made successively in as many plates, each unlike all the others in size, position and form.

The last carrier in the series deposits the recessed plate in a tube at the extreme right hand end of the the machine, By a change in chucks, etc., the turnings on the dial side of the plate can be made in a similar manner. The boldness in the conception of this machine. (Fig. 7) will be appreciated when it is realized that the watch plate must be placed in each succeeding chuck in a different position, and that it is required to be placed on three pins which fit in the three dial feet holes.

Another form of plate turning machine is designed for turning recesses in top plates, which are held in self-closing chucks, instead of being placed on pins as is the case with pillar plates. This machine, which is shown in the accompanying view, (Fig. 8) is exceedingly novel in its movements, especially in the action of the transfer carriers, which instead of swinging over, like those on the pillar plate machine, are made to swing around. This form of motion involves the necessity for an additional movement in a vertical direction to clear the tool carriage. In this case, as in the other, the blank plates are taken from a tube, where they have been placed by the attendant, and placed in the chuck, and are also delivered in another tube when completed. Another difference in action consists in the movement of the work toward the tool, instead of the tool toward the work. But the most novel and curious action is that of the transfer carrier. As this arm swings around, its ordinary effect would be to reverse the watch plate so that it would be placed in the succeeding chuck with

*i the opposite face presented to the cutting tool. In some cases that change would be desired, but where it is desired to make the successive recesses on the same side, the carrier reverses the plate during its transfer, so that it is placed in the second chuck with the same

Fig. Q. — Showing Recessing and Facing of Top Plates.

side out, but with the center of revolution at what ever point desired. The accompanying illustration, (Fig. 9) shows the several recesses and the facing of both sides of plates.

Chapter II

It should be understood that this work is not intended to describe the manufacture of watches, for that would require volumes, but to briefly note some of the steps in the evolution of special machines, which characterize the ••American system" of watchmaking. It must be understood that only a few of the more prominent machines can be considered, and that only a general description of those can be given.

Having briefly considerd the turning of the plates, we will defer, for a time, anv mention of other operations on that part of the watch movement, and review the successive forms of the machines for turning the various arbors, staffs and pinions, which constitute some of the moving parts of the watch.

The history of the American Waltham Watch Factory does not extend back to that indefinite period when power was obtained by means of the foot wheel, and the turning tool was simply a graver held in the hand of the operator; but only to the time of the lathe and slide-rest, whose feed-screw was operated by hand. For a time, the turning of all staffs and arbors was performed in this way. But this method was succeeded by a form of semi automatic turning lathe, the exact form of which the writer is unable to learn. Succeeding this, came an improved form of lathe, in which the tool was caused to move with a uniform speed and to a desired distance

Fig. 10. — Moseley- Webster Staff Turning Lathe.

and then automatically withdrawn from contact with the work and returned to the point of starting. The accompanying illustration, (Fig. 10), shows one of the oldest form of lathes used in this factory, which can be found (and unfortunately minus one of its spindles). It will be observed that at the left hand end of the machine there is a combination of levers, designed to provide for turnings of various lengths without necessitating a change of feed cams. It is the understanding of the writer that the combination levers were designed by Mr. Ambrose Webster, while the invention of the lathe should be credited to Mr. Chas. S. Moseley.

The next illustration (Fig. n). shows a later form of automatic staff turning lathe, which embodies substanti-

Fig. 11.— Staff Turning Lathe (Vander Woerd Pattern.)

ally the same principle of mechanism as the earlier machine, but differently arranged, and of much heavier construction. The cam shaft, at the back of the machine, is driven bv a worm and worm-gear, not shown. At the extreme left hand end of this shaft is shown the feed cam, the acting face of which gives motion to a rack lever, which indirectly communicates motion (endwise) to the tool carrying spindle, one end of which is seen projecting through the end of the machine. The opposite end of this spindle enters the projecting cylinder at the right hand side of the machine, which cylinder contains a spiral spring, which serves to carry the spindle in the reverse direction to that imparted by the feed cam. About midway of the length of this spindle is attached the tool holder, which is compound in its construction, to allow for the desired elevation of the turning tool, and also to provide a means of moving the tool at a right angle to the axis of the staff or arbor to be turned, this latter motion serving to withdraw the tool from contact with the work, or. when so desired, to enable the tool to perform a " squaring out " or " facing " cut. To effect this motion an arm of the tool carriage extends back underneath the cam shaft and is acted upon by a suitable cam. which depresses the arm, and thereby slightly turns the feed or tool carrying spindle, thus moving the tool away from the work, and, while thus held back, the action of the feed cam allows the tool to return to its starting point, in readiness to act upon the next piece of work. Devices for so governing the action of the tool as to turn taperingstaffs are also provided, but cannot be seen in a general view. In staff turning it is sometimes desired to have one of the spindles in which the work runs fixed and the opposite one movable, to allow of the reception and removal of the work, and at other times it is needful to make the opposite spindle the tixed one. Readv provision is made for these requirements by means of suitable binders, or clamps provided with milled nuts, shown on the front of the spindle heads. When one of these nuts is screwed down so as to clamp the spindle firmly in place, the opposite one is turned back so as to leave the spindle on that side free to slide. When the staff to be turned is inserted in position, the free spindle is moved up into proper contact with it, and as the lathe is put in motion, a suitable cam on the rear shaft acts through an adjustable lever, and binds the slide spindle in place until the turning tool has completed its work and has returned to its starting point, when the spindle is released and can be slid back, and the completed arbor removed.

This brief, and perhaps not very clear explanation of the action of this staff turning lathe, is given for the benefit only of those readers who have had no opportunity of visiting a watch factory. As has already been said, this is substantially the form of staff turning lathe

EVOLUTION OF AUTOMATIC MACHINERY.

in use in American watch factories, and probably to some exent may have found its way into some European factory also.

Some years ago the writer designed another form of staff lathe, which, while in many respects similar to the

Fig. 12. — Marsh Staff Turning Lathi foregoing, yet possessed several features of novelty and special advantage. The accompanying illustration, (Fig. 12), will serve to give a general idea of its appearance. It was much more heavy and solid, and consequently assured a greater accuracy. It also had superior devices for taper turning in either direction, and in connection with such turning, it provided for facing either, hollow, crowning, or at a right angle to the axis. It was also arranged to turn special pieces in which a part of the turning was to be straight and when a certain point was reached the turning continued at any desired angle.

Machines of all the above forms are to a large degree becoming obsolete in the American Waltham Watch factory, they having been largely displaced by the radical improvements designed by Mr. D. II. Church. It should be said in connection with all the forms of staff turning lathes above described, that they are but semi-automatic. Each piece to be turned, required to be "dogged" as a means of driving; the dog engaging with a suitable linger, or horn, on the driving whirl. The applying and removing of the " dogs " giving constant and lively employment to the attendant, and making impossible the running of more than a single lathe by one operator.

In the earlier days of American watchmaking the pinions were to a great extent made from ''drawn pinion wire." but in later years the use of such special wire was discontinued, and the use of plain round steel wire was adopted. For years it was customary to cut the plain wire into short pieces, making suitable allowance in length for finish. The common way was to "chop off" the wire by means of an ordinary wire cutter or by a special chopping machine. These short pieces were then placed one by one in a spring chuck in a lathe, and one end carefully pointed. After the entire lot had been pointed on one end, they were placed in another chuck, provided with a suitable interior stop, against which the pointed ends of the blank should bear, in order to insure exactness in the length of the blanks. Subsequent " rough turning " of these blanks, which were still held in spring chucks, removed a large portion of the surplus metal, bringing them into a suitable condition to be turned in the automatic staff lathes. When acted upon in the staff lathes the blanks were held and revolved on " dead centers," each piece as has been said, requiring to be dogged by the operator.