Watch and Clock Escapements

rselves strictly to the designing and construction as employed in our best watches. By designing, we mean giving full instructions for drawing an escapemen

viders with pen and pencil points-one pair of these dividers to be 5" and the other 6"; one ruling pen. Other instruments c

air of dividers set at precisely 5", as shown (reduced) at a a and b b. On these arcs we set off the space held in our dividers-that is 5"-as shown at the short radial lines at each end of the two arcs. Now it is a well-known fact that the space embraced by our divi

n our minds the fact that the extent of a degree depends entirely on the radius of the arc we employ. To aid in this explanation we refer to Fig. 2. Here the arcs c, d, e and f are all fifteen degrees, although the linear extent of the degree on the arc c is twice that of the degree on the arc f. When we speak of a degree in connection with a circle we mean the one-three-hundred-and-sixtieth part of the periphery of such a circle. In dividing the arcs a a and b b we first di

PAIR OF

(C) being a round handle turned from hard wood or ivory. The slot l is sawn in, and two holes drilled in the end to insert the needle points i i. In making the slot l we arrange to have the needle points come a little too close together to agree with the d

h a carefully-made prick punch. After the arc a a is divided, the brass plate A is cut back to this arc so the divisions we have just made are on the edge. The object of having two arcs on the plate A is, if we desire to get at

NG AN ESC

t m m, Fig. 4. At 5-1/2" from the lower margin of the paper we establish the point p and sweep the circle n n with a radius of 5". We have said nothing about stretching our paper on the drawing-board; still, carefully-stretched paper is an important part of nice and correct drawing. We shall subsequently give directions for properly stretching paper,

English lever watches. This form of escapement gives excellent results when well made; and we can only account for it not being in more gen

e ratchet-tooth lever escapements of later dates have almost invariably been constructed on the ten-degree lever-and-pallet-action plan; that is, the

AND-FOR

said lines a b, to the lines a c and a c', the fork has what we term ten-degree pallet action. If the fork and pallets vibrate six degrees on each side of the line a b-that is, to the lines a d and a d'-we have twelve degrees pallet action. If we cut the arc dow

during as much of the arc of the vibration of the balance as possible, and yet have the action thoroughly sound and secure. Where a ratchet-tooth escapement is thorou

drawing at Fig. 6 we show the circle n n, which represents the periphery of our esc

alf teeth of the escape wheel. There are two systems on which pallets for lever escapements are made, viz., equidistant lockings and circular pallets. The advantages claimed for each system will be discussed subsequently. For the first and present illustration we will assume we are to employ circular pallets and one of the teeth of the escape wheel resting on the pallet at the point f; and t

THE CENTER OF

7, can be employed. To use such a triangle, we place it so the right, or ninety-degrees angle, rests at e, as shown at the dotted triangle C, Fig. 6, and the long side coincides with the radial line p e'. If the short side of the hard-rubber triangle is too short, as indicated, we place a short ruler so it rests against the edge, as shown at the dotted line g e, Fig. 7, and while holding it securely down on the drawing we remove the triangle, and with a fine-pointe

propelled through an arc of eight and one-half degrees, while the escape wheel is moving through an arc of ten and one-half degrees. We make the arc of fork action eight and one-half degrees for two rea

ESCAPE-WH

rne in mind that at the point f is located the extreme point of an escape-wheel tooth. On the arc a a we lay off from p twenty-four degrees, and establish the point b; at twelve degrees beyond b we establish the point c. From f we draw t

mmencing at f and continued as shown at o o until the entire wheel is divided. We only show four teeth complete, but the same methods as produced these will produce them all. To briefly recapitulate the instructions for drawing the teeth for th

sed forward in the direction of the arrow j, the tooth D would press on the arc l and be held. If, however, we should revolve the arc l on the center k in the direction of the arrow i, the tooth D would escape from the edge of l and the tooth D'' would pass through an arc (reckoning from the center p) of twelve degrees, and be arrested by the inside of the arc l at e. If we now should reverse the motion and turn th

ION IS

a "hairspring." We are all aware that for the motive power for keeping up the oscillations of the escaping circle l we must contrive to employ power derived from the teeth D of the escape wheel. About the most available means of conveying power from the escape wheel to the oscillating arc l is to provide the lip of said arc with an inclined plane, along which the tooth which is disengaged from l at f to slide and move sai

the reader into the why and how, and point out to him the rules and methods of analysis of the problem, so that he can, if required, calculate mathematically exactly how many grains of force the fork exerts on the jewel pin, and also how much (or, rather, what percentage) of the motive power is lost in various "power leaks," like "drop" and lost motion. In the present case the mechan

eations we would recommend the horological student to make drawings on a flat me

AND-FOR

al drawing was made for an escape wheel ten inches in diameter. We shall make a radical departure from the usual practice in making cuts on an enlarged scale, for only such parts as we are talking about. To explain, we show at Fig

space. The arc a, Fig. 9, represents the periphery of the escape wheel. On this line, ten and one-half degrees from the point of the tooth A, we establish the point c and draw the radial line c c'. It is to be bor

emedy has been devised to overcome it. All the other escapements, including the chronometer, duplex and cylinder, are quite as wasteful of power, if not more so. It is usual to construct ratchet-tooth pallets so as to util

ne e g we draw the line e h. For delineating the lines e g, etc., correctly, we employ a degree-arc; that is, on the large drawing we are making we first draw the line e b f, Fig. 10, and

and-pallet action, and with equidistant lockings. If we reason on the matter under consideration, we will see the tooth A and the pallet B, against which it acts, part or separate when the tooth arrives at the point c; that is, after the

he inner angle of our pallet. In delineating this angle, Moritz Grossman, in his "Prize Essay on the Detached Lever Escapement," makes an error, in Plate III of large English edition, of more than his entire lock, or ab

method of establishing the angle as we made use of in drawing the lines e g and e h, Fig. 10. The line j establishes the locking face of the pallet B. Setting the locking face of the pallet at twelve degrees has been found in practice to give a safe "draw" to the pallet and keep the lever secure against the bank. It will be remembered the face of the escape-wheel tooth was drawn at twe

ING GOOD DRAWI

th due precision, mechanical designs or drawings. Ordinary drawing instruments, even of the higher grades, and costing a good deal of money, are far from being satisfactory to a man who has the proper idea of accuracy t

steel wire which will fit a No. 16 chuck of a Whitcomb lathe, and drilling a hole in the end about one-fourth of an inch deep and about the size of a No. 3 sewing needle. We Show at Fig. 12 a view of the point A', Fig. 11, enlarged, and the steel tube we have just drilled out attached at C. About the best way to attach C is to solder. After the tube C is attached a hole is drilled through A' at d, and the thumb-screw d inserted. This thumb-screw should be of steel, and ha

such cones can be turned carefully, then hardened and tempered to a straw color; and when they become dull, can be ground by placing the points in a wire chuck and

represents the spring and A the leg of the dividers. The spring D has a short steel tube C'' and set-screw d'' for a fine point like B or B'. In the lower end of the leg A, Fig. 14, is placed the mill

ING SCREW FOR DRA

To make (because they cannot be bought) such an instrument, take a piece of flat steel, one-eighth by three-eighths of an inch and seven inches long, and after turning and smoothing it carefully, make a slide half an inch wide, as shown at Fig. 15, with a set-screw h on top to secure it at any point on the bar E. In the lower part of the slide F is placed a steel tube like C, shown in Figs. 12 and 14, with set-screw for holding points like B B', Fig. 13. At the opposit

the spring G; but in case this is done it would be better to make another spring like G without the point j, and with the adjusting screw placed at l. In fitting pen and pencil poin

DETACHED LEVER ES

tion of diagram III, from Moritz Grossmann's "Prize Essay on the Detached Lever Escapement," in order to point out the error in delineating the e

only use eight and one-half degrees, the same mistake would give proportionate error if we did not take the means to correct it. The error to which we refer lies in drawing the impulse face of the entrance pallet. The impulse face of this pallet as d

ls to mind a wood model of a lever escapement made by one of the "boys" in the Elgin factory about a year or two after Mr. Grossmann's prize essay was publ

ader. In reply let us analyze the action of the tooth B as it rests on the pallet A. Now, if we move this pallet through an angular motion of one and one-half degrees on the center g (which also represents the center o

angular motion of the pallet staff for the tooth to escape, because the tooth certainly must be disengaged when the inner angle of the pallet reaches the peripheral line a. The true way to locate the position of the inner angle of the pallet, is to measure down on th

e of the entrance pallet A seems to extend inward, beyond the radial line a j, that is, toward the pallet center g, and gives the appearance of being much thicker than the exit pallet A'; but we will see on examination that the

hery of the escape, as shown in the drawing, where it extends beyond the intersection of the line g f

ere G represents the grindstone and N N' the cold chisels. The grindstone is supposed to be revolving in the direction of the arrow. The chisels N and N' are both being ground, but the chisel N' is being cut much the more rapidly, as each particle of grit of the s

TY FOR GOOD

any reliance can be placed. The drawing of a ratchet-tooth lever escapement of eight and one-half degrees pallet action will now be resumed. In the drawing at Fig. 18 is shown a complete delineation of such an escapement

of the escape wheel. In this drawing it is not important that the entire escape wheel be shown, inasmuch as we have really to do with but a little over sixty degrees of the periphery of the escape wheel. With the dividers carefully set at five inches, from a

the point b establish the point c, which embraces the arc of the escape wheel which is utilized by the pallet action. Through the point b the line h' h is drawn at right angles to the line a b'. The line j j' is al

nd i on the arc f represents the locking face of the entrance pallet, and the point formed at the intersection of the line g i with the arc f is called the point p. To give the proper lock to the face of the pallet, from the point p as a center is swept the short arc r r, and from its intersection with the line a b' twelve degrees are laid off and the line b s drawn, which defines the locking face of the entrance pallet. From g as a center is swept the arc c' c', intersecting the arc n n at c.

NG THE EX

elow this line is drawn the line g m. The space on the arc f between these lines defines the locking face of the exit pallet. The point where the line g m intersects the arc f is named the point x. From the point x is erected the line x w, per

arc v' v' through the point v. It will be evident on a little thought, that if the tooth A' impelled the exit pallet to the position shown, the outer angle of the pallet must extend down to the point v,

ortion and mechanical elegance. Ratchet-tooth pallets are usually made in what is termed "close pallets"; that is, the pallet jewel is set in a slot sawed in the steel pallet arm, which

NG CIRCUL

t point, and with the dividers set at five inches, sweep the arc m, to represent the periphery of the escape wheel, and then draw the vertical line A B', Fig. 19. We (as before) lay off thirty degrees on the

ive degrees, said five degrees being half of the angular motion of the escape wheel utilized in the present drawing, and thus establish the point c, and from A as a center draw through this point the radial line A c'. To the r

rees and draw the line B g, which establishes the extent of the lock on the entrance pallet. It will be noticed the linear extent of the locking face of the entrance pallet is greater than that of th

uidistant locking faces; that is, the inner angle of the entrance pallet (shown at s) does not have to be carried down on the arc d' as far to insure a continuous pallet action of ten d

OUNT O

the line B f, and, as a consequence, the absolute lock of the tooth C on the locking face of the entrance pallet E is but about one degree. Under these conditions, if we did not extend the outer angle of the exit pallet at t down to the peripheral line m, we would s

degree in any mechanical matter demanding such extreme accuracy as the parts of a watch. It has been claimed that such defects can, to a great extent, be remedied by setting the escapement closer; that

F MAKING LA

ntersection with the peripheral line m one and a half degrees, and establish the point r and thus locate the outer angle of the entrance pallet E, so there will really be one and a half degrees of lock; and by measuring down on the arc d' ten degrees from its intersection with the peripheral l

the point n, which locates the position of this inner angle; and, of course, one and a half degrees added on the arc d' indicates the extent of the lock on this pa

OOTH LEVER

much favor is, we think, chiefly owing to the fact that this form of tooth is better able to stand the manipulations of the able-bodied watchmaker, who possesses more strength than skill. We will not pause now, how

rselves in many changes of the relations of the several parts. With the ratchet tooth the principal changes we could make would be from pallets with equidistant lockings to circular pallets. The club-tooth escape wheel not only allows of circular pallets and equidistant lockings, but we can divide the impulse between the pallets and the teeth in such

As relates to the escape-wheel action of the ten and one-half degrees, which gives impulse to the escapement, five and one-half degrees are utilized by the driving planes on the teeth and five by the impul

and through the points so established on the arc a a we draw the radial lines A b and A c. From the intersection of the radial line A b with the arc a we draw the line h h at right angles to A b. Where the line h intersects the radial lines A B' is located the center of the pallet staff, as shown at B. Inasmuch as we decided to let the pallet utilize five deg

. From the intersection of the radial line A g with the arc a we lay off to the left five and a half degrees on said arc, and through the point so established draw the radial line A f. With the dividers set at five inches w

h. We draw a line from the intersection of the radial line A f with the arc i to the intersection of the radial line A g with the arc a, and thus define the impulse face of the escape-wheel tooth D. For defining the locking face o

ack of the tooth, the small circle at n denoting one of the centers just described. The length for the face of the tooth was obtained by taking eleven degrees from the degree arc just referred to and laying that space off on the line p, which defined the face of the tooth. The line B k is laid off one and a half degrees below B h on the arc m. The extent of

OF THE SEV

pallet of our escapement, let us reaso

known escapement. Most-we had better say all, for there are no exceptions which occur to us-writers on the lever escapement lay down certain empirical rules for delineating the several parts,

would be located on a line drawn tangent to the circle a a from its intersection with the radial line A k, Fig. 21. Such a tangent is depicted at the line s l'. If we reason on the situation, we w

however, that we could locate the center of the pallet action at the small circle B' above the center B, which we h

ection of the addendum circle i and the arc g, and located at o. It is also self-evident that the inner or locking angle must be situated at some point

ide the pitch circle a. With the dividers set at 5", we sweep the short arc b b, and from the intersection of this arc with the line B c we lay off ten degrees, and through the point so established

NNER ANGLE OF

angle at o. We draw the line n o and define the impulse face of the exit pallet. If we mentally analyze the problem in hand, we will see that as the exit pallet vibrates through its ten degrees of arc the line

e draw the line n u, which defines the locking face of the exit pallet. We draw the line o o' parallel with n u and define the outer face of said pallet. In

lse from the pallets than from the teeth. We do this to show the horological student the facility with which the club-tooth lever escapement can be manipulated. We wish also to impress on his mind the facts that the employment of t

o sort of tinkering we can do to give such a watch a good motion, except to change either the escape wheel or the pallets. If we know enough of the lever escapement to set about it with

WITH EQUIDISTAN

and establishing the center of the escape wheel at A, and with the dividers set at 5" sweep the pitch circle a. On each side of the intersection of

at the crossing or intersection of said line with the vertical line A k establish the center of the pallet staff, as indicated by the small circle B. From B as a center sweep the short arc l with a 5" radius; and from the intersection of the radial line A b with the arc a continue the line f unti

we denominate the point o, and from this point as a center sweep the short arc p with a 5" radius; and on this arc, from its intersection with the radial line A b, la

tone at C was made to conform to the radial line A b, the lock of the tooth D at o would be "dead"; that is, absolutely neutral. The tooth D would press the pallet C in the direction of the arrow x, toward the center of the pallet staff B, wi

ion. But it is evident on inspection that a locking face on the line A b would cause a retrograde motion of the escape wheel, and consequent resistance, if said pallet was moved in either direc

OF ESCAPE WHE

tion of the escape wheel utilized by the pallet, we lay off seven degrees on the arc a from the point o and establish the point n, and through the point n, from B as a center, we sweep the short arc n'. Now somewhere on this arc n'

the pallet was located. In the present instance the addendum line w becomes the controlling arc, and it will be further noticed on the large drawing that the line B h at its intersection with the arc n' approaches ne

name the point so established the point r. The outer angle of this pallet is located at the intersection of the radial line A b with the line B i; said intersection we name the point v. Dra

the impulse face of the tooth, and indicated between the lines B h and B f; one and a half degrees lock b

FROM FORME

rom this beaten track we will draw our exit pallet as locked. There are other reasons which prompt us to do this, one of whi

allet as illustrated at Fig. 23, could not do it correctly. Occasionally one could do it, but the instances were rare. A still greater poser was to request them to delineate a pallet and tooth when the action

ILLUS

ement of the watches made by one factory would "set," that is, if you stopped the balance dead still, with the pin in the fork, the watch would not start of itself; while the escapement designed by the other draughtsman would not "set"-stop th

ich we need not repeat. Previous to drawing the exit pallet, let us reason on the matter. The point r in Fig. 23 is located at the intersection

a half degrees, we establish the lock of the pallet E. To get this one and a half degrees defined on the arc k, we set the dividers at 5", and from B as a center sweep the s

t the point r, we sweep the short arc t, and from the intersection of said arc with the line A c we draw the line n p; but in doing so we extend it (the l

ersection of this line with the arc k we name the point z. With one leg of our dividers set at A we sweep the arc l so it passes through the point z. This last arc de

TER ANGLE OF TH

r, we sweep the short arc m. It will be evident on a moment's reflection that this arc m must represent the path of movement of the outer angle of the exit pallet, and if we measure down ten degrees from the intersection of the arc l with the arc m, the point so established (which we name the point s) must be the exact position of the outer angle

ESCAPEME

0" one we have been drawing. In the accompanying cuts are shown only the main plate and bridges in full lines, while the positions of the escape wheel and balance are indicated by the dotted circles I B. The cuts ar

way at R, while N shows a glass cover, and M a wooden base of polished oak or walnut. This base is recessed on the lower side to receive an eight-day spring clock movement, which supplies the motive power for the model. This base is recessed o

wo pillars 1/2" in diameter and 1-1/4" high. Fig. 25 is a side view of Fig. 24 seen in the direction of the arrow p. The cock D is also of 1/8" spring brass shaped as shown, and attached by the screw f and steady pins s s to the top plate C. The bridge F G

of the escape wheel. On the same line a at 1.15" from d we establish the point b, which represents the center of the pallet staff. At the distance of 1.16" from b we establish the p

leg rests at the center m and the other leg at the point d, we sweep the arc t. With the dividers set at 1.33" we establish on the arc t, from the point d, the points e e', which locate the

nist turned the casting up, as it was too large for an American lathe. A hairspring had to be specially made, inasmuch as a mainspring was too short, the coils too open and, more particularly, did not look we

THE B

e bridges to the pillars which support them, and also other small circles to indicate the position of the pivot holes d b for the escape wheel and pallet staff. I

ed in the main plate A at d. We now place a nicely-fitting steel pin in the hole d' in the bridge F and let it extend into the hole d in the main plate. We clamp the bridge F to A so the

upright. The pillars which support the bridges are shaped as shown at Fig. 28, which shows a side view of one of the pillars which support the top plate

at Fig. 29. The heads of such screws should be about 3/8" in diameter and nicely rounded, polished and blued. We would not advise jeweling the

ES FOR CAPPING

d is employed the cost will not be much, as the settings are only about 3/8" across and can be turned very thin, so they will really contain but very little gold. The reason why we re

e. There is a new phosphorus glass used by optical instrument makers which is intensely hard, and if colored ruby-red makes a beautiful pallet jewel, which will afford as much service as if r

at a short piece of brass wire can be screwed upon it, as shown in Fig. 31, where h represents the pivot, A the lower plate, and the dotted line at p the brass piece screwed on the end of the pivot. This piece p is simply a short bit of brass wire with a female screw tapped into the end, which screws on to the pivot. An arm is attached to p, as shown at T. The idea is, the pieces T p act like a lathe dog to convey the power from one of the pivots of an old eight-day spring clock movem

R EXPLAINING

ation ruby pallets dipping in and out of the escape wheel. A model of this kind is far more attractive than if the entire train were shown, the mystery of "What makes it go?" being one of the attractions. Such a model is,

ls (hole and cap) are arranged. Where the parts are as large as they are in the mo

r recommending the reader not to jewel the holes of his model. The extra cock is to be shown, not for use, an

E SCREWS

polished, does not look well, neither does a flattened conehead, like Fig. 35. The best head for this purpose is a cupped head with chamfered edges, as shown at Fig. 34 in vertical section. The center b is ground and polished into a perfect concave by means of a metal ball. The face, between the lines a a, is polished

SCRE

oxide of iron. (2) The surface of the screwhead is coated with a very thin coating of shellac dissolved in alcohol and thoroughly dried, or a thin coating of collodion, which is also dried. The screw is placed in the ordinary polishing triangle and the flat face at a polished on a tin lap with diamantine and oil. In polishing such surface

d plates and bridges. The frosting should not be a fine mat, like a watch movement, but coarse-grained-in fact, the grain of the frosting should be proportionate to the

long by 1-1/2" wide, answer first rate. We show at A A A A, Fig. 37, such a box as if seen from above; with a side view, as if seen in the direction of the arrow a, at Fig. 38. A piece

O ACID F

s in the shape of small round pellets called "mastic tears," crush these into dust and place the dust in A. Let us next suppose we wish to frost the cock on the balance, shown at Fig. 39. Before we commen

t necessary to frost any portion of the cock C, except the upper surface. To protect the portion of the cock not to be frosted, like the edges and the back, we "stop out" by painting ov

EPARE THE

cess of mastic. Holes should be made in this paper and also in the board on which the paper rests to receive the steady pins of the cock. We hold the sieve containing the mas

s to frost a few scraps to "get your hand in." Nitric acid of full strength is used, dipping the piece into a shallow dish for a few se

TCH THE

r dissolves the brass, leaving a little brass island the size of the particle of mastic which was attached to the surface. After heating to attach the particles of mastic, the dipping in nitric

he air. A little turpentine on a rag will remove the mastic, but turpentine will not touch the shellac coating. The surface of the brass will be found irregularly acted upon, producing a sort

coating. All the screw holes like s s and d, also the steady pins on the back, are protected by varnishing with shellac. The edges of the cocks and bridges should be polished

lator cap C is cut out to the correct size. These parts are of decarbonized cast steel, annealed until almost as soft as sheet brass. It is not so much work to finish these parts as one might imagine. Le

the piece of mainspring assumes the form shown at Fig. 42, where c represents the piece of spring and H H the bench-vise jaws. The piece of soft steel is placed between t

oft steel and G the cold chisel. We might add that Fig. 42 is a view of Fig. 43 seen in the direction of the arrow f. It is well to cut in from the edge b on the line d, Fig. 41, with a saw, in order to readily break out the

not believe with what facility pieces can be shaped. Any workman who has a universal face plate to his lathe can turn out the center of the regulator bar to receive the disk C, and also turn o

Swiss screw-plate. The wire from which such screw is made should be 1/10" in diameter. The steel cap C is fitted like the

AND POLI

may serve as a support for the regulator during heating and hardening. A paste made of castile soap and water applied to the regulator bar in the iron envelope will protect it from oxidizing much during the heating. The portions of the regulator bar marked h are intended to be rounded, while the parts marked m are intended to be dead flat. The rounding is carefully done, first with a file and finished with emery paper. The outer edge of the loop A'' is a little rounded, also the inner edge next the cap C. This will be understood by inspecting Fig. 46, where we show a

EEL POLISHI

accessories few and inexpensive. First, ground-glass slab 6" by 6" by 1/4"; second, flat zinc piece 3-1/4" by 3-1/4" by 1/4"; third, a piece of thick sheet brass 3" by 2" by 1/8"; and a bottle of Vienna lime. The glass slab is only a piece of plate glass cut to the size given above. The zinc slab is pure zinc planed dead flat, and the glass ground to a dead surface with ano

, they look better to be nicely rounded. Perhaps we can convey the idea better by referring to certain parts: say, spring to the

e sections of D, Fig. 50, on the line f. The edges of D, in Fig. 48, are simply rounded. There are no rules for such rounding-only good judgment and an eye for what

G AND PO

lat and brilliant, the rounded edges, like g c can really have quite an inferior polish and still look well. For producing the flat polish on the upper surface of the regulator bar B and spring D, the flat surfac

A of heavy sheet iron, something about 1/8" thick, and secure the two together with three or four little catches of soft solder. It is to be und

th shellac dissolved in alcohol and well dried. The object of this shellac coating is to keep the angles formed at the meeting of the face and side clean in the process of grinding wit

e final polish is obtained on the zinc lap with Vienna lime and alcohol. Where lathe cement is used for securing the regulator to the plate A, the alcohol used with

HAT IS MOST

in a shape to give satisfaction to his customers. No one will dispute the truth of the above italicised statement. I

ements with equidistant lockings, ten degrees lever and pallet action, with one and one-half degrees lock and one and one-half degrees drop. Another workman would insist on circular pallets, his judgment being based chiefly on

SHOULD KNOW TO

xcess to the tooth. Now while these matters demand our attention in the highest degree in a theoretical s

rcular pallets and those with equidistant locking faces; but before we do so we wish to impress on our readers the importan

UDGE OF ANGULAR AS W

still give a good, sound action. All workmen should learn to estimate accurately the extent of angular motion, so as to be able to judge correctly of escapement actions. It is not only nec

Fig. 53. Here we have the base line A A' and the perpendicular line a B. Now almost any person would be able to see if the angle A a B was equal to B a A'; but not five in one hundred practical mechanics would be able to estimate with eve

m carefully-made drawings; or, what is better, constructing a model on a large scale, that we can learn to judge of proper proportion and relation of parts, especially as we have no co

is about the right thing for good results. In this day, when such a large percentage of lever escapements have exposed pallets, we can very readily manipulate the pallets to match the fork and roller action. For that matter, in man

D ROLLE

as we have stated, frequently the fork and roller are principally at fault. In considering the action and relation of the parts of the fork and roller, we will first define what is considered necessary to constitut

onstruction. Manufacturers have made departures from this standard, but in almost every instance have finally come back to pretty near these proportions. In deciding on the length of fork and size of roller, we firs

ER DIAMETER FROM THE

he third space will represent the point at which the pitch circles of the fork and roller will intersect, as shown by the arc a and circle b. Now if the length of the radii of these circles stand to ea

, or, in ordinary horological phraseology, have a greater arc of roller action, we would extend the length of fork (say) to the point c, which would be one-fifth of the space between A and B,

S OF ROLLER ACTIO

for the jewel pin to engage the fork, as short an arc as is compatible with a sound action. (b) It will be evident to any thinking mechanic that the acting force of a fork which would carry the jewel pin against the force exer

well. In this matter there has been a broad field gone over, both theoretically and in practical construction. Wide jewel pins, round jewel pins, oval jewel pins have been employed, but practical construction has n

ORK AND ROLLER

ved that there are three important actions in the fork and roller functions: (a) The fork imparting perfect impulse through the jewel pin to the balance. (b) Proper unlocking action. (c) Safety action. The last function is in most instances sadly neglected and, we regr

y of the action of the roller and fork. While writing on this topic we would suggest the importance not only of knowing how to draw a correct fork and roller action, but letting the workman who desires to be au fait in escapem

s in several stages of action. By this course they will educate the eye to discriminate not only as to correct actions, but also to detect those which are i

nce between the center of the pallet staff and the center of the balance staff equal in length the chord of ninety-six degrees of the pitch circle of the escape wheel, wh

NEATE A FOR

B as a center we sweep the short arc c. From our arc of sixty degrees, with a 5" radius, we take five degrees, and from the intersection of the right line A B with the arc c we lay off on each side five

n degrees on each side of the line A B on the arc f, and establish the points g h. From A as a center, through the points just e

is, on the arc f we establish the points l m at six degrees from the line A B, and through the points l m draw, from A as a center, th

THE SIZE OF

, and from it as a center we sweep the circle i so it passes through the intersection of the lines A l' and A m' with the arc a. We divide the radius of the circle i on the line A B into fi

impulse. We commence the drawing at Fig. 57, as before, by drawing the line A B and the arcs a and b to represent the pitch circles. We also sweep the arc f to enable us to delineate the line A g'. Next in order we draw our jewel pin as shown at D. In drawi

OF THE FO

ng will show that in allowing thirty degrees of contact of the fork with the jewel pin, the center of the jewel pin will pass through an arc of thirty degrees, as shown on the arcs a and f.

viously stated, we assume the jewel pin, as shown at D, Fig. 57, is in the act of encountering the inner face of the horn of the fork for the end or purpose of unlocking the engaged pallet

inner face of the prong of the fork-we would also call attention to the fact that relations of parts are precisely the same as if the jewel pin had just

from A and B as centers draw the pitch circles c d. By methods previously described, we draw the lines A a and A a', also B b and B b' to represent the angular motion of the two mobiles, viz., fork and roller action. A

d, we sweep the small circle D, Fig. 58, which represents our jewel pin; we afterward cut away two-fifths and draw the full line D, as shown. We show at Fig. 59 a portion of Fig. 58, enlarged four times, to show certain p

TE THE PRONGS

mits the length of the opposite prong of the fork. The outer face of the prong of the fork can be drawn as a line tangent to a circle drawn from A as a center through the angle n of

we consider double-roller action. The extent or length of the outer face of the prong is also an open subject, but as there is but one factor of the problem of lever escapement construction depending on it, when we name this and se

of the fork, or when it passes into the fork in the act of unlocking the escapement. In escapements with solid bankings a trifl

R LENGTH

E' the jewel pin parts from the fork, or engages on its return. To do this we draw a line from the center r (Fig. 59) of the jewel pin, so as t

ingress or egress to the jewel pin to the slot in the fork. As regards the length of the outer face of the prong of the fork, a good rule is to make it one and a half times the diameter of the jewel pin. The depth of the slot need be no

NEATE THE S

uard pin is to strike the edge of the roller A at any time when the fork starts to unlock the engaged pallet, except when the jewel pin is in the slot of the fork. To avoid extreme care in fitting up the passing hollow, the horns of the fork are arranged to strike the jewel pin and prevent unlocking in case the passing hollow is made too wide. To delineate the safety action we first draw the fork and jewel pin as previously directed and as shown at Fig. 63. The position of the guard pin should be as c

and effectual. We previously stated that the jewel pin should occupy about twelve degrees of angular extent on the circle c, and if we make the passing hollow occupy eighteen degrees (which is one and a half the angular extent of the jew

ork and roller action it is safe to show the guard pin as if in actual contact with the roller. Then in actual construction, if the parts are made to measu

ition and relation of parts exist which is all we can desire. We are aware that it is usual to give a considerable latitude in this respect e

E FRICTIONA

he assertion that we should in all instances seek to reduce the extent of all frictional surfaces, no matter how well jeweled. Acting under such advice, if we can reduce the surface friction on the lock from one and a half degrees to one degree

f the practical watch repairer. It is to be supposed in this problem that the fork and roller action is all right. The reader may say to this, why

Faults may also be those arising from repairs by some workman not fully posted in the correct form and relation of the several parts which go to make up a lever escapement. It makes no difference to the artisan called upon to put a watch in pe

REPAIRS, IF SUR

rgensen watch had been in the hands of several good workmen in that city, but it would stop. It was then brought to him with a statement of facts given above. He knew there must be a fault somewhere and searched for it, and found

er that such a thing could exist as a fault in construction in a watch of this justly-celebrated maker. The writer removed the

AN ESCAPE

s named. It will be seen by careful inspection that the jewel pin D will not enter the fork, which is absolutely necessary. This condition very frequently exists in watches where a new pallet stone has been put in by an inexperienced workman. Now this is one of the instances in which workmen co

scape on either pallet. Put the balance in place and screw down the cock. Carefully turn back the banking on one side so the jewel pin will just pass out of the slot in the fork. Repeat this process with th

THE PALLETS TO

they will. It is not a very difficult matter after we have placed the parts together so we can see exactly how much the pallet protrudes beyond what is necessary, to judge how far to push it back when we have it out

that with a fork which engages the roller for eight degrees of fork action, such fork will not give good results with pallets ground for ten degrees of pallet action; still, in many instances, a compromise can be effected

jewel pins and how to set them. We have heretofore only considered jewel pins of one form, that is, a round jewel pin with two-fifths cut away. We assumed this form from the fact tha

JEWEL PIN AS

pin "a world too wide" for it, and we have heard repeated complaints from this cause. Probably the original object of this accommodating sort of hole was to favor or obviate faults of pallet action. Let

to coincide with either of dotted circles a or a', Fig. 65. This will perhaps be better understood by referring to Fig. 66, which is a view of Fig. 65 seen in the direction of the arrow c. Here we see the roller jewel at D, and if we bring it

eing necessary. We do not assert, understand, that a hole too large for the jewel pin is either necessary or desirable-what we wish to convey to the reader is the necessary knowledge so that he can profit by such a state if necessary.

WEL-PIN

examination when the jewel pin is in the proper position to perform its functions correctly, and he can only arrive at this knowledge by careful study and thought on the matter. If we make up our minds on examining a watch that a jewel pin is "set t

of tweezers, "flashing it" back and forth through the flame of a rather small alcohol lamp until the rim of the balance is so hot it can just be held between the thumb and finger, and while at this temperature the jewel pin can be pressed forward or backward, as illustrated in Fig. 66, and then a touch or two will set the pin straight or parallel with the staff. Figs. 68 and 69 are self-explanatory. For cementing in a jewel pin a very convenient tool is shown at Figs. 67 and 70. It is made of a piece of copper wire about 1/16" in diameter, bent to the form shown at Fig. 67. The ends b b of the coppe

AN ANGLE-MEA

said before, which is to the effect that ten degrees of fork and lever action is not imperative, as we can get just as sound an action and precisely as good results with nine and a half or even nine degrees as wi

nown as a milliner's needle is about the best. The diameter of the needle should be about No. 2, so that at b we can drill and put in a small screw. It is important that the whole affair should be very light. The length of th

e made of a bit of mainspring, annealed and filed down to agree in width with the part A. In connection with the device shown at Fig. 71 we need a movement-holder to hold the movement as nearly a constant height as possible abov

ULAR MOTION

the train, and with an oiling tool or hair broach move the lever back and forth, the index hand A' will show in a magnified manner the

f wire extending down into the support E, and made adjustable as to height by the set-screw l. Let us suppose the index arc is adjusted to the index hand A', and we move the fork as suggested; you see the hand would show exactly the arc passed through from bank to bank, and by moving the stand E F we can arrange so the zero ma

ND DROP WITH O

ite bank, and in the same manner determine if the lock is right on the other pallets. You see we have now the means of measuring not only the angular motion of the lever, but the angular extent of the lock. At first glance one would sa

hairspring and put the balance in place. Now, if the jewel pin passes in and out of the fork, it is to be supposed the fork and roller action is all right. To test the fork and roller action we close the banking a little on one side. If the fork and jewel pin are related to each ot

e warn them that they are no easy problems to solve, but require good, hard thinking. The readiest way to master this matter is by means of such a model escapement as we have described. With such a model, and the pallets made to clamp

S WITH OUR ANGLE

t be taken that the spring clamp which embraces the pallet staff does not slip. In order to thoroug

hand A, Fig. 72, we can determine with great exactness the angular extent of lock. The diagram at Fig. 75 illustrates how this experiment is conducted. We apply the hair broach to the end of the fork M, as shown at L, and gently move the fork in the direction of the arrow i, watching the hand A and note the number of degrees, or parts of degrees, indicated by the hand

lever almost rests on the banking pin. What the reader should impress on his mind is that the lever should pass through about one and a half degrees arc to unlock, and the remainder (eight and a half degrees) of the ten degrees are to be devoted to impulse. But, understand, if

adopting ten degrees of fork and roller action with the table roller, except that about this number of degrees of action are required to secure a reliable safety action. With the double roller, as low as six degrees fork and pallet action can be safely employed. In fork and p

E ANGULAR MOTION

n the engaged tooth rests on the locking face of a pallet, the index hand stands at the extreme end of our arc of twelve degrees. We next, with our pointed pegwood, start to move the fork away from the bank, as before, we look sharp and see the index hand move backward a little, indic

four degrees, and the impulse derived from the escape wheel, as illustrated at Fig. 76, will often fall below eight degrees. Such watches will have a poor motion and tick loud enough to keep a policeman awake. Trials with actual watches, with such a device as we have just described, in conjuncti

require another index hand, with the grasping end bent downward, as shown at Fig. 77. The idea with this form of index hand is, the bent-down jaws B', Fig. 77, grasp the fork as close to the pallet staff as possible, making an allowance for the acting center by so placing the ind

NTROLS THE TIMEK

educing the arc of fork and roller action; (2) reducing the friction of the guard point to a minimum. While it is entirely practicable to use a table roller for holding the jewel pin with a doubl

he balance in motion; (b) to classify and record the number of vibrations of the balance. Hence, it is of paramount importance that the vibrations of the balance should be as untrammeled as possible; this is why we urge reducing the

to some extent on the necessity of the several parts being made on correct principles. For instance, by reducing the a

meter, but of the same weight as one in an ordinary eighteen-size movement. We can readily see that such a balance would require but a very light hairspring to cause it to give the usual 18,000 vibrations to the hour. We can also understand, after a little thought, that such a balance would exert as mu

C PRESSURE AF

ar the periphery as is consistent with strength, is what is to be desired for best results. It is the moving matter composing the balance, pitted against the elastic force of the hairspring, which we have to depend upon for the regularity of the timekeeping of a watch, and if we can take two

pin a; (2) the part A'' and hole b, which goes on the balance staff; (3) the counterpoise A''', which makes up for the weight of the jewel socket A, neck A' and jewel pin. This counterpoise also makes up for the passing hollow C in the guard roller B, Fig. 80. As the piece A is always in the same relation to the roller B, the poise of the balance must always remain the same, no matter ho

ees of roller action. We will also point out the necessary changes required to make it adapted for eight degrees of fork action. We would beg to urge again the advantages to be derived fr

ore required than in fork and roller action. We are led to say the above chiefly for the benefit of a class of workmen who think there is a certain set of rules which, if they could be obtained, would enable them to set to rights any and all escapements. It is well to understand that no such system exis

THE DOUBLE-RO

acting roller; (2) two-thirds of the size of the acting roller. The chief fault urged against a smaller safety roller is, that it necessitates longer horns to the fork to carry out the safety action. Longer horns mean more metal in

k and pallet action of a watch, and torsional motion is something seldom brought to act on a watch to an extent to make it worthy of much consideration. In the double-roller action which we shall consider, we shall adopt three-fifths of the pitch diameter of the jewel-pin action as the proper size. N

n in which the fork and pallet action is reduced to eight degrees. We shall conceive the play between the guard point

ION OF DOUBLE R

. The circle b b represents the pitch circle of the jewel pin, and the circle at c c the periphery of the guard or safety roller. The points established on the circle c c by intersection of the radial lines A d and A d' we will denominate the points h and h'. It is at these points the

in the direction of the arrow j, letting the guard point rest constantly in such notch. When the notch n in c has been carried through thirty degrees of arc, counting from B as a center, the guard point, as relates to A as a center, would only have passed through an arc of five degrees. We show such a guard point and notch at o n. In fact, if a jewel pin was set to engage the fork on the pitch circle b a, the escapement would lock. To obviate such lock we widen the notch n to the extent indicated by the dotted lines n'

A DOUBLE-ROL

will give, at Fig. 82, a very well proportioned and practical form of fork. The pitch circle of the jewel pin is indicated by the dotted circle a, and the jewel pin of the usua

extent of the passing hollow is only a little over thirty-two degrees. The passing hollow E is located and defined by drawing the radial line B c from the center B through the intersection of radial line A i with the dotted arc b, which rep

e fork F we draw the short arc g, from A as a center, and on said arc locate at two degrees from the center at B the point f. We will designate the upper angle of the outer face of the jewel pin D as the point s and, from

s practically the same as the radius of the circle a, and consequently of the same curvature. Practically, the length of the guard point C' is made as long as will, with certainty, clear the safety roller B in all positions. While we set the point f at two degrees f

ee of lock. In the perfected lever escapement, which we shall describe and give working drawings for the construction of, we shall describe a detached lever escapement with only eight degrees fork an

UARD POIN

stening the guard point is equally efficient as that of attaching it with a screw, and much lighter-a matter of the highest importance in escapement construction, as we have already urged. About the best material for such guard points is either aluminum or phosphor bronze, as such material is lighter than gold and very r

eatures of his drawing, Fig. 1, plate VIII, of his "Modern Horology," in which he makes the draw of the locking face of the entrance pallet fifteen degrees and his exit pallet twelve degrees. In the cut shown at Fig. 84 we use the same letters of reference as he employs. We do n

TANGENTIA

he position of the pallet staff from the circle t, which represents the extreme length of the teeth; drawing the radial lines A D and A E to embrace an arc of sixty degrees, and esta

hich represents the locking angle of the teeth. This would have placed the center of the pallet staff farther in, or

-tooth escapement all that part of a tooth which extends beyond the line s should be considered the same as the addendum in gear wheels. Consequently, a tangential locking made to coincide with the center of the impulse plane, as recommended by Saunier, would require the pallet staff to be located at C' instead of C, as he draws it. If the angle k' of the tooth k in Fig. 84 was extended outward from the center A so it would engage or rest on the locking face of the entrance pallet as shown at Fig. 84, then the draw of the locking angle would not be quite fifteen degrees; but i

the radial A G changes when the pallet moves through the angle w C w', as it must when locked. A tangential locking in the true sense of the meaning of the phrase is a locking set so that a pallet with its face coinciding with a radial line like A G would be n

tudent can very readily be misled. Faulty drawings, when studying such problems, lead to no end of errors, and practical men who make imperfect drawings lead to the

DRAWING

th such drawings, we will find our lever to "hug the banks" in every instance. It is inattention to such details which produces the errors of makers

5, is the theoretically correct position fo

ong which are the thickness of the pallet arms, which establishes the angular motion of the escape wheel utilized by such pallet arms, and also the angular motion imparted to the pallets

r of the pallet staff. The intersection of the line A B with the arc a we term the point d, and from this point we lay off on said arc a thirty degrees each side of said intersection, and thus establish the points c b. From A, through the point c, we draw the line A c c'. On the arc a a and

A f', such locking face would be strictly "dead" or neutral. The intersection of the line f e with the line A B we call the point C, and locate at this point the center of our pallet staff. According to the method of de

s mind this is not just as it should be, and may lead to misunderstanding and bad construction. We should always bear in mind the fact that the basis of a locking face is a neutral plane placed at right angles to the line of thrust, and the "draw" comes from a lo

AL LO

the line m m, which is at right angles to the line c D. If we should now make a locking face with a "draw" and at an angle to the line c D, say,

ith the radial line A k'; and a locking face with twelve degrees draw would coincide nearly with the line l. Let us next analyze what the effect would be if we changed the pallet center to h', Fig. 88, leaving the engaging tooth sti

f by accident the fork is moved away. We are well aware that it takes lots of patient, hard study to master the complications of the club-tooth lever escapement, but it is every watchmaker's duty to conquer the problem. The definition of "lock," in the detached lever escapement, is the

e. This maxim applies particularly to the entrance pallet. We would beg to add that practically it will make but little odds whether we plant the center of our pallet staff at C or h, Fi

NTS FOR LEVE

abuse the minds of our readers of any such notions. Although the lever escapement, as adopted by our American factories, is constructed on certain "lines," still these lines are subject to modifications, such as may be demanded for ce

nes a b are supposed to represent an angular movement of ten degrees. Now, it is the function of the fork to carry the power of the train to the balance. How well

f the balance has to actually turn the train backward and against the force of the mainspring. True, it is only through a very short arc, but the necessary force to effect this has to be discounted from the po

lock down to three-quarters of a degree, a perfection easily to be attained by modern tools and appliances. We shall also cut the drop down to three-quarters of a degree. By these two economies we more than make up for the power lost in unlocking. With highly polis

TED LEVER

actical workman can be embodied in the following question: What proportion of the power derived from the twelve degrees of angular motion of the escape wheel is really conveyed to the fork

LOST IN THE LE

care, the drop can be cut down to three-quarters of a degree, or one-half of the loss with the ratchet tooth. We do not wish our readers to imagine that such a condition exists in most of the so-called f

tion is seldom looked after as carefully as the situation demands. Our factories make the impulse face of the pallets rounded, but leave the locking face flat. We are aware this condition is, in a degree, necessary from the use of exposed pallets. In

present the center of action of the fork. We can readily see that the fork in a state of rest would stand half way between the two banks from the action of the hairspring, and in the pallet action the force of the escape wheel, one tooth of which rests on the impulse face of a pallet, would

CLUB-TOOTH

after winding (if run down) without shaking or any force other than that supplied by the train as impelled by the mainspring. In the drawing at Fig. 90 we propose to utilize eleven degrees of escape-wheel action, against ten and a half,

eader will please bear in mind that we do not give these proportions as imperative, because we propose to give the fullest evidence into the reader's hands and enable him to judge for himself, as we d

ial to the pitch circle a from the point of tooth contact at f. To establish this point we draw the radial lines A c and A d from the escape-wheel center A, as shown, by laying off thirty degrees on each side of the intersection of the vertical line i (passing through the centers A B) with the arc a, and then laying off two and a half degrees on a and establishing the point f, and through f from the center A draw the radial l

f pallet or lever motion we must shape it to this end. We draw the short arc k through the point n, knowing that the inner angle of the pallet stone must rest on this arc wherever it is situated. As, for instance, when the

ATE THE PA

of our pallet stone, we draw the line B b', which passes through the point n located at the intersection of the arc a with the arc k. From B as a center we sweep the short arc j with any convenient radius of which we have a sixty-degree scale, and from the intersection of B b' with j we lay off five degrees and draw the line B s', which establishes the point s on the arc k. As stated above, we allow one degree

passing through the point l. The intersection of the arc m with the line A h we call the point r, and by drawing the right line r f we delineate the impulse face of the tooth. On th

N" DRA

umed are arrived at by mental processes, without making the proper drawings to show the actual relation of the parts at the time such conditions exist. For illustration, it is often urged that there is a time in the acti

of the tooth has passed the pallet. The position of the entrance pallet when locked is sufficiently well shown in Fig. 90 to give a correct idea of the relations with the entrance pallet; and to conform to statement (2), as above. We will now delineate the entra

measurements for pallet actions are from the center of the pallet staff at B. As we desire to now delineate the entrance pallet, it has passed through five degrees of angular motion and the inner angle s now lies on the pitch circ

PEMENT TO SHOW

f the short arcs x'' x''' and to the point t we draw the line t y. The reader will see from our former explanations that the line t y represents the neutral plane of the locking face, and that to have the proper draw we must delineate the locking face of our pallet at twelve degrees. To do this we draw the line t x' at twelve degrees to the line t y, and proceed to outline our pallet faces as shown. We can now understand, after a moment's thought, that we can delineate the impulse face of

let C will touch the impulse face of the tooth. To prove this we draw the radial line A v through the point where the short arc t t' passes through the impulse face w of the tooth D. Then we continue the line w to n, to represent the impulse face of the tooth, and then measure the angle A w n between the lines w n and v A, and find it to be approximately sixty-four degrees. We then, by a similar p

LEMS IN THE LE

stablish the escape-wheel center at A, and from it sweep the arc b, to represent the pitch circle. We next sweep the short arcs p s, to represent the arcs through w

lay off three degrees on each side of the point s and establish the points d m, we have located on the arc b the angular extent of the tooth to be drawn. To aid in our delineations we draw from the center A the radial lines A d' and A m', passing throug

ee of angular motion of the escape wheel such condition takes place; because to determine such relation mathematically requires a knowledge of higher mathematics, which would require more study than most p

find by analysis of our drawing that parallelism takes place about the time when the tooth has three degrees of angular motion to make, and the pallet lacks about two degrees of angular movement for the tooth to escape. It is thus evident that the relations, as shown in our drawing, are in favor of the train or mainspring power over hairspring resistance as thr

for the briefest duration, in a practical sense, because theoretically these surfaces never slide on each other as parallel planes. Mathematically considered, the theoretical plane represent

ALLET IN AN

t draw a radial line from B inside of the line B e to show where the outer angle of the impulse plane commences, but the reader will see that the impulse plane is drawn one degree on the arc p below the line B e. We continue the line h h to represent the impulse face of the tooth, and measure the angle B n h and find it to be twenty-seven degrees. Now suppose we wish to delineate the entra

let in the new position. We draw a line parallel with v t from the intersection of the line v y with the arc p, and we define our locking face. If now we revolve the

S APPLIED TO THE

d more efficient aid to practical mechanics than has been afforded by the graphic solution of abstruce mathematical problems; and if we add to this the means of correction by

Fig. 93 we measure the distance on the line b between the points (centers) A B, and we thus by graphic means obtain a measure of the distance between A B. Now, by the use of trigonometry, we have the length of the line A f (radius of the arc a) and all the angles given, to find the length of f B, or A B, or both f B and A B. By adopting this policy we can verify the measurements taken from our drawings. Sup

R CLOSE MEASUREM

to the point B was one-fifteenth of the diameter of the escape wheel, this ratio would hold good in the actual watch, that is, it would be the one-fifteenth part of .26". Again, suppose the diameter of the escape wheel in the large drawing is 10" and the distance between the centers A B is 5.78"; to obtain

"; we make a similar statement to the one above, thus: 10 : .47 :: .26 to the actual thickness of the real pallet stone. By computation we find it to be .0122". All angular relations are alike, whether

GE ESCAPEM

id not make and measure the abstractions which they delineated on paper. We do not mean by this to endorse the cavil we so often hear-"Oh, that is all right in theory, but it

ght and wrong, and thus practically demonstrate a perfect action and also the various faults to which the lever escapement is subject. The pallet arms are shaped as shown at A, Fig. 94. The pallets B B' can be made of steel or stone, and for all practical purp

Fig. 99. This disk E is permanently attached to the plate C. The lever shown at Fig. 99 is attached to the disk E by two screws, which pass through the holes h h. If we now place the brass pieces D D' on the plate C i

e shown at Fig. 95, we could only turn the disk D on the screw b; but if we enlarge the screw hole in C to three or four times the natural diameter, and then place the nut e under C to receive the screw b, we can then set the disks D D' an

NS WITH FORK AN

ther about this now, and only call attention to the capabilities of such adjustments when required. At the outset we will conceive the fork F attached to the piece E by two screws passing through the

in hand is to find out by mechanical experiments and tests the consequences of such a change. It is evident that the angular motion of the pallet staff will be increased, and that we shall have to open one of the banking pins to allow the engagin

pallet to three degrees, provided we were working on a basis of one and a half degrees lock; and if we pushed back the exit pallet so as to have the proper degree of lock (one and a half) on it, the tooth which would next engage the e

ations which follow even such a small change, we will find the job a lengthy one. But with a large model having adjustable parts we provide ourselv

N THE DETACHED

pallets (which were adjustable) in all sorts of ways, right ways and wrong ways, so he could watch the results. A favorite pastime was to set every part for the best results, which was determined by the arc of vibration o

t g. To facilitate the description we reproduce at Fig. 102 the figure just mentioned, and also employ the same letters of reference. We fancy everybody who has any knowledge of the lever e

ler would cause the engaged tooth to pass off the locking face of the pallet, and the fork, instead of returning against the banking, would cause the guard pin to "ride the roller" during the entire excursion of the jewel pin. This fault produces a scraping sound in a watch. Suppose we attempt to remedy the fault by bending forward the guard pin b, as indicated by the dotted outline b' in Fig. 103, said figure being a side view of Fig. 102 seen

already been described, but of smaller size, for measuring fork and pallet action. The device to which we allude is shown at Figs. 104, 105 and 106. Fig. 104 shows only the index hand, which is made of steel about 1/20" thick and shaped as s

URE ESCAPEM

n. For measuring pallet action we only require ten degrees, and for roller action thirty degrees. The arc C, Fig. 105, can be made of brass and is about 1-1/2" long by 1/4" wide; said arc is mounted on a brass wire about 1/8" diameter, as shown

8" long, through which drill axially a hole to receive the wire k. After the jaws B'' are clamped on the pallet staff, we set the index arc C so the hand B' will indicate the

mpulse, we set the index arc C so that the hand B' marks ten degrees for the entire motion of the fork, and when the escapement is locked we move the fork from its bank and notice by the arc C how many degrees the hand indicated before it

ON OF "RIGH

. We have also often heard the remark that there was only one right way, but any number of wrong ways. Now we are inclined to think that most of the people who hold to but o

his certain method. One workman believes in equidistant lockings, another in circular pallets; each strong in the idea that their particular and peculiar method of designing a lever escapement w

chief arguments in favor of the ratchet tooth are: (a) It will run without oiling the pallets; (b) in case the escape wheel is lost or broken it is more readily replaced, as all ratchet-tooth escape wheels are alike, either for circular pallets or e

ENTS CO

h we hold this as of small import, as any workman who is competent to repair watches would never injure the delicate teeth of an escape wheel; (c) ratchet-tooth lever escapements will occasionally need to have the pallets oiled. The writer is inclined

ments; hence, we have so much contention about oiling pallets. The writer does not claim to know positively that the pallet stones are at fault because some escapements need oiling, but the fact must admit of explanation some way, and is this not at least a rationa

permits greater power to be utilized at the close of the impulse. This feature we have already explained. It is no doubt true that it is more difficult to match a set of pallets with an escape wheel of the club-tooth order than

n a new escape wheel and find we have on the entrance pallet too much drop, that is, the tooth which engaged this pallet made a decided movement forward before the tooth which engaged the exit pallet encountered the locking face of said pallet. If we thoroughly under

ET PALLE

e should thoroughly understand exactly what we desire to accomplish. In setting pallet stones we must take into consideration the relation of the roller and fork a

ngle a c' of the fork. The circle described by the jewel pin B is indicated by the arc e. It is well to put a slight friction under the balance rim, in order that we can try the freedom of the guard pin. As a rule, all the guard pin needs is to be free and not touch the roller. The entire point, as far as setting the fork and bankings is concerned, is to have the fork and roller action sound. For all ordinary lever escapements the angula

e can for the money he gets for the job. In the instance given above, of the escapement with nine degrees of lever action, when the fork worked all right, if we undertook to give the fork the ten degrees demanded by the stickler for accuracy we would have to set out the jewel pin or lengthe

necessary to measure the angle of fork action as long as it is near the proper thing, and then bring the pallets to match the escape wheel after the fork and rolle

have the correct lock on the next succeeding pallet. The tooth should fall but a slight distance before the tooth next in action locks it, because all the a

we set the banking screws so that the teeth will just escape from each pallet. By the term "fall" we mean the arc the tooth passes through before the next pallet is engaged. This action is also illustrated at Fig. 108, where the tooth D, after dropping from the pallet C, is arrested at the position shown by the dotted outline

e adjusting them. As shown at Fig. 107, the fork A' is banked a little close and t

N ESCAPEMENT

must hold the watch plate A exactly parallel with the bed plate B. In the cheap movement holders these seats (a) are apt to be of irregular heights, and must be corrected for our purpose. We will take it for granted that all the seats a are of precisely the same height, measured from B, and that a watch plate placed in the jaws C will be held exactly parallel with the said bed B. We must next provide two pillars, shown at D E, Figs. 109 and 111. These pillars furnish support for sliding centers which hold the top pivots of the escape wheel and pallet staff while we are testing the depths and adjusting the pallet stones. It will be understood that these pillars D E are at right angles to the plane of the bed B, in order that t

were in their place between the plates of the movement. The foot of the pillar D has a flange attached, as shown at f, which aids in holding it perfectly upright

TTING UP ESCA

e base plate B. The slide G N on the pillar D can be made of two pieces of small brass tube, one fitting the pilla

order that the center I may be readily and accurately set. The parts H F are shown separate and enlarged at Figs. 115 and 116. The piece H can be made of thick sheet brass securely attached to F in such a way as to bring the V-shaped groove at right angles to

. 115, or a flat plate of No. 24 or 25 sheet brass of the size of H can be employed, as shown at Figs. 116 and 117, where o represents the plate of No. 24 brass, p p the small screws attaching the plate o to H, and k a clamping screw to fasten I in position. It will be found that the two ligh

revent turning, we should cut away about two-fifths, as shown at Fig. 119, which is an end view of Fig. 118 seen in the direction of the arrow c. In such flattening we should not on

ATCHING DEVI

eve G a piece of wire of the same size as F but with three-fifths cut away, as shown at y, Fig. 121. This piece y is soldered in the sleeve G so its flat face stands vertical. To give service and efficiency to the screw h, we thicken the side of the sleeve F by adding the stud w, through which the screw h works. A soft metal plug goes between the screw h and the b

in precisely the same position and relation to each other as if the lower plate was in position. It is further to be supposed that the balance is in place and the cock screwed down

ET PALLE

this we need to have the shellac which holds the pallet stones heated enough to make it plastic. The usual way is to heat a piece

lamp so it will do its duty, and after a little practice the setting of a pair of pallet stones to perfectly perform their functions will take but a few minutes. In fact, if the stones will answer at all, three to five minutes is as much time as one could