Helpful Information for Watchmakers (3rd Edition, 1918)

HELPFUL INFORMATION WATCHMAKERS BY 0LOF0HLS0N GENERAL SUPERINTENDENT 3d Edition 30,000‐1918 WALTHAMWATCHCOMPANY WALTHAM, MASS. FOREWORD WE take pleasure in providing for Watchmakers this booklet containing a brief explanation of certain recent improvements that have been made in the mechanical construction of Waltham Watch Movements. We have also added a few notes of a more general character, which we trust will be of interest and some usefulness. WALTHAM TAPER SHOULDER DETACHABLE BALANCE STAFF (PATENTED) As used in OS, 1900, 12s, Model B Colonial Series and 16s, ‘99, Waltham Movements This is an improved form of a detachable Balance Staff that is certain to appeal to the watchmaker, as it admits of easily and quickly changing a staff without bending the balance arm or throwing the balance out of shape. The bevel seating in the hub B fits precisely the taper shoulder F on the staff, thus insuring a level balance. To drive o u t an oldstafi,werecommendusingatoolasshowninFig.4; toputinanewstaff,apunch,as showninFig.3,bringingthetaperedshoulderonthestafftoitsbearinginthehub. Tools designed for these staffs can be obtained from watch t o o ] manufacturers in sizes to fit regular staking tool sets. The blue steel hub should always be left in the balance arm when changing a staff. | ‘a,ll“| 4:55:51;0.s OHM/VG//y 7bOL. flfi/V/A'e Our 7bOL. 4 DH L m , MUM? 72/pr fflouwffi [JAE/27mm5414/fo J 71W. ‘\ x iW WALTHAM HAIRSPRING STUD A common practice in removing a watch balance, is to lift it by the hair‐ spring, whose stud is left attached to the balance cock. This method, while con‐ venient, involves the danger of possible injury to the hairspring. By the improved stud, herewith illustrated, such danger isavoided. It is simply needful to t u r n back the stud-holding screw sufiicient to allow the stud to swing freely from its place, thus detaching the hairspring from the balance cock which can then be removed. After replacing the balance, screw the balance cock into place, then hold the move‐ ment onedgeandallowthestudtoswingintoposition,thenfastenintoplacebyitsscrew. WALTHAM SPIRAL WINDING,PINIONAND CROWN WHEEL As used in the latest 12and 16size movements The Waltham Watch Company has solved the difficult problem of transmitting power, at a right angle, from the winding arbor to the winding wheel. smooth winding action is produced by the special form of spiral teeth of the Winding Pinion and the rounded cycloi‐ dal working faces of the teeth in the Crown Wheel, as shown in the accom‐ panying drawing. For the making of these parts, special automatic machin‐ ery has been designed and built at the Waltham factory. An absolutely WALTHAM SAPPHIRE JEWELED MAIN WHEEL Asusedin our18sVanguardandCrescentStr.’92modelmovementswith19ormoreJewels; 16s’99modelmovementswith19or more Jewels; 14sColonialA; ColonialSeries and 12s Riverside and Maximus grade movements. This main wheel is fitted with two jewels, forming the bearings, which t u r n on the barrel arbor during the running of the watch. As shown on page 8, the arbor is composed of two parts, A and B. Part A is squared on its upper end to receive the winding wheel; next to this is a round part (with a shoulder) that turns in the plate during winding. Below this shoulder or flange is the body of the arbor, on which the main wheel turns. It has an axial hole through its entire length, tapped with a double right-hand thread. Into its lower end is screwed part B, which, with its square and shoulder, holds the steel barrel in place. To separate, hold the barrel by the thumb and finger of one hand, place on the square of the winding arbor the winding wheel or a key, and t u r n backwards. A special tool for this purpose, asshown in the illustration on page 8,can beobtainedfrom dealers in watch tools. www 1W1 IIIIW \ HMIIIIIIIIHIIIIIH ‘4 ll/l/l/ // W a i n Me (26 and‘é‘a/weé Msaemblect. J’Zfl/NMAEEL, ”474W'‐C9. 11fw1mmu..\.1.\1\.1\111111111111\| \/ “511111 ’J/// //////////// WALTHAM RECOILING CLICK Theobjectinusingarecoilingclickistwofold: first,toreleasetheinitialhightension after the winding of the watch, resulting from torsion in the barrel arbor and abnormal stress in the main‐ spring which some‐ times, when a plain click is used and the w a t c h is wound care‐ lessly, will cause the balance to “over-bank” and gain time in a very erratic way. Second: If a mainspring is wound very tight, and not released immediately, the oil will be squeezed out, causing excessive friction between the successive turns of the spring, resulting in a falling off in the motion of the balance. These difficulties are overcome in a very efficient manner by the use of o u r recoiling spring click shown in t h e illustrations here‐ with. 1‘ WALTHAM TAPER STEADY PINS In theplateworkofwatchmovements,steadypinsareusedforthepurposeofplacing, and accurately relocating, parts that have to be removed at times for cleaning, etc. Steady pins should fit closely in their holes, and still let go freely when the screws are loosened. Under such conditions there is very little danger of bending or breaking pivots, in p u t ‐ ting together, or taking apart, watch movements. Theserequirementsarebroughtto perfection in Waltham Watches by the taper steady pins and holes. (See drawing.) These are made on special automatic machines, by which the watch plate and the part that is to be fitted are held firmly while the pins are turned and the holes in which they are to fit are bored at the same time. This method ensures exact location as well as proper fit. 12 WALTHAM PENDANT SETTING MECHANISM The Waltham Pendant Setting Mechanism consists of the Shipper A, Shipper Lever B and Shipper Spring C. The normal position of these parts with the setting teeth of the clutch in engagement with the hand setting wheels, is shown in the accompanying drawing. If the watch is to be ' r u n out of the case, the shipper bar D should be pulled outward. This acting on the shipper at E shifts the clutch from the setting to the winding position and leaves the setting wheels free. THE SIZE OF A WATCH MOVEMENT As a matter of interesting information relating to thedescriptionof Americanwatch movements, as being of certain designated “sizes,” let us say that this system of meas‐ urement is identical with that established and used by English watchmakers, and relates to the extreme diameter of the pillar plate. Being English, its unit of measurement is the E n g l i s h i n c h , a n d t h e z e r o , or s t a r t i n g p o i n t , is one inch plus five-thirtieths of an inch (1350), w h i c h is the diameter of an 0 size movement. Each go- of an inch added to this measurement represents the size of a movement. Therefore 1350 plus 310 will be the diameter of a one size movement; a six size should measure 1‐5‐5, a twelve size lgg, an eighteen Size lgg, etc. N O T E : In order to express this in millimeters we must multiply by 25.4, which is the metric equivalent of an inch, sothe general formula will be (gal-5513?) X 25.4; and the formula for 12size, (gig‐PH) X 25.4 = 39.8 millimeters. 13 WALTHAM LEVER ESCAPEMENT The proper action of the human heart is no more essential to insure a sound and healthy body, than is the properadjustment and action of the escapement to the reliable performance of the watch. If the watch escapement is properly made and adjusted, it will n o t only r u n , ‐but will r u n with marvelous accuracy. So the time-keeping qualities of the watch are in large measure dependent on the condition of the escapement. It is, therefore, of great importance that every watchmaker should acquire an intimateknowledge of all the actions that are involved in the kinds of escapements with which he has anything to do. The only kind of escapement used in Waltham Watches is the detached lever escape‐ ment, sometimes designated as the anchor escapement. This escapement requires no special introduction to watchmakers, for by extensive use, and by the test of time, it has beenproven to be the most practical as well as the most reliable form of escapement for pocket timepieces. We insert in this booklet some drawings of the lever escapement that they m a y be convenient for reference, and an aid to the clear understanding of the test. The function of the escapement is to impart to the balance, regularly, and with as small loss as possible, the power which has been transmitted through the train from the mainspring to the escape pinion. In the lever escapement this is accomplished by means of t w o distinct actions:‐ first, the action of the escape wheel and pallet; second, the action of the fork and roller pin. The drawing on page 16 is a plan view of the Waltham Lever Escapement, as used in the 16size, 1899, and 18size, 1892 model, movements, drawn toscale10tol, andgivingthenamesoftheprincipalpartsandfeaturesofthesame. The Loam/c5405 \ WPULSEfiref ‐ ‐ » 604/90 P/IV \\\‘f// \ ‐‐‐‐‐ ’,‐_§\ \\ . I,/ \ \ HOLLfR // \\ escape wheel is mounted friction tight on the slightly tapered staff of the escape pinion. It hasfifteenteeth,called“ClubTeeth”onaccountoftheir peculiar shape,resultingfrom t h e a d d i t i o n o f i m p u l s e faces t o t h e ends o f t h e t e e t h , a n d t o d i s t i n g u i s h t h e m f r o m “ r a t c h e t teeth,” the n a m e givento a style of pointed teeth used on escape wheels in an earlier f o r m of lever escapement. In descriptions of this escapement the t e r m “exposed pallets” is used. This means that the pallet stones are visible, with the active ends standing out free from the body of the pallet, asdistinguished from an earlier form of pallet with “covered stones” set in slots running in the plane of the pallet. THE PALLET ACTION The action of the escape wheel and pallet includes the following features: impulse, drop, lock, draft and slide, and in giving a general description of these actions we will con‐ sider briefly what constitutes each one of these features. The pallet is of the kind called “circular pallet,” which meansthat the distance from the pallet arbor to the middle of the impulse face is the same for both pallet stones. Another kind of pallet is made with “equidistant lock,” that is, the distance from the pallet arbor to the point where the lock takes place, is the same for both pallet stones. The pallet is mounted on its arbor, which is located close to the periphery of the escape wheel. A theoretically correct distance in , relation to the diameter of the escape wheel will n o t allow an excess of clearance between the pallet and the escape wheel teeth when opposite the pallet arbor, and for that reason the amount of stock in the pallet is made very small at that point. The pallet is slotted 1WALTHAM 1 for the two pallet stones in such a way as to make the inside corners of the pallet stones reach over three teeth of the escape wheel, and to make the outside corners of the stones reach over two teeth and three spaces of the wheel, with a small a m o u n t of clearance in each instance, which is called the “drop.” One other important p o i n t in relation to the slotting is to direct the slots in the p a l l e t i n s u c h a w a y a s t o m a k e t h e l o c k i n g faces o f e a c h o f t h e p a l l e t s t o n e s p r e s e n t t o t h e locking corners of the escape wheel teeth a certain angle.of “draw” when the stones are in the position of “lock.” We will t r y to make this condition clear by referring to the drawing on page 22. Suppose that the escape wheelis being forced in the direction indi‐ cated by the arrow, but is prevented from turning in that direction because the locking face of the R pallet stone is directly in the way of a tooth. The particular tooth which is resting on the pallet stone is exerting a certain pressuredirectly towards the pallet arbor. If thelockingfaceofthepalletstonewerealongthelineB,whichisatarightangletothat lineofpressure,therewouldbenotendencyforthepallettoturnin eitherdirection,but being along the line C, which forms an inclined plane in relation to the direction of the pressure, the pressure applied by the escape wheel tooth will tend to pull the pallet stone toward the escape wheel. This action is called the “draft” or “draw.” The turning of the pallet is, however, limited by the banking pin, and the object of the draw is to keep thefork againstthebankingpinallthe timethatit isnotin engagementwiththe jewel pin. This action of “draw” is similar on the L stone; the only differences are, first, that the pressure of the escape wheel tooth is exerted in the direction away from the pallet arbor, instead of towards it, and, second, that the turning of the pallet, which in this instance is in the opposite direction, is limited by the other banking pin. ‐ A glanceat the drawingon page22willmakeit apparentthattheimpulseface,which is formed by the surfacebetweenthe locking and the let-off corners, is at a different angle on the R from that on the L stone. The impulse angles of the stones in the escapement, represented by this drawing, are, on the R stone, 6°30’, and on the L stone 18°. The above refers in each instance to the angle of the impulse face in relation to a r i g h t angle to the locking face, or to the body of the stone. From this condition and from the direction of the pallet stones in relation to the body of the pallet, the factory names “straight” and “crooked” have been given to the R and L stones, respectively. In books and treatises on the lever escapement the names “receiving” and “discharging” are used, but when, as a matter of fact, both pallet stones perform the functions of receiving and discharging, one asmuchastheother, thesenamesdonotseemto beappropriate. Forourpartweprefer to use the letters R and L to distinguish one stone from the other, and these letters m a y easily be remembered as right and left, this being the order in which the stones appear as we look at the top of the pallet with the fork turned towards us. The impulse or l i f t is divided between the escape wheel clubs and the pallet stones; the two together cause the pallet to turn through an angle of 8°30’; the lock amounts to Loaf/Ne5405 \ ‘WPULSE54sz " 7 ° " 604,70 P/A/ \\\ \ \ ROLLffi \\, \\\ \__,/ ,/ from 1° to 1°30’, making the total angular motion of the pallet about 10°. This is the condition when the pallet is “banked to drop,” that is, when the teeth of the escape wheel willjustbarely passby thelet-oficornersof thepalletstonesastheforkcomesto restagainst the bankings. A certain a m o u n t of clearance, or freedom, has to be added to this to allow f o r o i l , e t c . , s o t h a t t h e b a n k i n g s have t o b e t u r n e d a w a y f r o m t h e c e n t e r l i n e a s m a l l a m o u n t t o a l l o w f o r w h a t i s c a l l e d “ s l i d e , ” t h a t i s , t h e p a l l e t s t o n e w i l l slide a v i s i b l e a m o u n t i n t o the escape wheel, after the escape wheel tooth drops on to the same. The amount of slide should, however, be very small, because it causes loss of power, by increasing the resistance to unlocking, as, in order to unlock, the escape wheel actually has to be turned backwards against the power of the mainspring, and the a m o u n t of this recoil is in proportion to the lock and slide added together. It is therefore important to notice the action of every tooth of the escape wheel on both pallet stones, to ascertain that each pallet stone has some slideoneverytooth,andtoallowonlyasmallamountintheplacewhereit appearstobe closest. 23 ROLLER AND JEWEL PIN One problem in connection with lever escapements, which every watchmaker has hadmoreor lessexperiencewith,hascometo afinalsolutionin theWalthamDoubleRoller Escapement. This is the fastening of the jewel pin. The roller, which holds the jewel pin,ismadeofbronze,withaholein it theshapeofthepin,butacertainamountsmaller than the pin. The jewel pin is made of sapphire, and is made slightly tapering, and is forced intothe hole in the roller, thus making it permanently secure. The shape of the jewel pin is round, with one side flattened off to measure three-fifths of the diameter of the pin, and the sharp corners removed. This form of jewel pin is superior in general practice to any other form, asit unites strength with the most desirable shape at the points of action. The principle of setting the jewel p i n directly in the roller, without cement, is made possible by the Double Roller Escapement, because of the special roller for the safety action. It would n o t be practical to set jewel pins without cement in steel rollers as it is in bronze, neither would it be advisable to use bronze roller for the safety action, because it has been found by experience that tempered steel is better for that purpose. But, by separatingt h e t w o features, it makes a m o s t desirable combination to use a bronze roller for carrying the jewel pin, and a separate steel roller for the safety action. 26 MATCHING THE ESCAPEMENT The term “matching the escapement” is used to designate the work of bringing the different parts of the escapement into correct relation to each other; in other words, to make the necessary moves in order to obtain the proper lock, draft, drop, slide, fork length, let-off, etc. The best way of learning to do this work is to have a competent in‐ structorwhoisathandreadytoinspectandtogiveadvice. Thedifficultiesarenotsogreat in doing this work, as in correctly determining what to do, in order to bring about certain results, and also to know when the escapement is in a proper condition. It is difficult to give in writing a comprehensive idea of how to do this work. We will, however, give a few points which we hope will be useful to the beginner. T h e fi r s t t h i n g t o receive a t t e n t i o n i s t h e c o n d i t i o n o f t h e p i v o t s o n t h e escape p i n i o n , palletarborandbalancestaff,to seethattheyarestraight,andthattheyfit properlyin their respective holes. It is absolutely necessary that each pivot should have some side shake, b u t it is also very important to guard against too much side shake, as such an excess causes loss of power and uncertainty in the action of the escapement. A desirable amount of side shakeis.01mm.,andit shouldnotexceed.015mm.,andtheamountofendshakeshould be from .02 to .05 m m . As soon as these points have been found to be correct, we are ready to t r y the “lock” and the “drop.” In describing the pallet action, on page 23, we made the statement that the lock should amount to from 10to 1°30’ This statement is, of course, of no practical use unless we are equipped with the necessary instruments for measuring this angle. We m a y , however, use the thickness of the pallet stones for com‐ parison and obtain practically the same results, by making the amount of lock equal to 1107 to %thethicknessof thestone,fromthelockingto the let-off corner. This corresponds very closely to the above angular measurements. If the pallet stones are to be moved, in order to change the a m o u n t of lock, it is very important to first consider what will be the 28 effect of a certain move, besides the alteration of the lock. The drop, for example, is effected very rapidly by moving the L stone. Hence, if the drops are equal, we should make the change in the lock by moving the R stone. If the lock is too strong, and the drop is largest on the outside, the L stone should be moved. If the lock is too strong, and the drop is largest on the inside, it is necessary to move both stones. Move the L stone o u t a small amount,andmovetheRstoneinuntilthelockiscorrect. Itisalsowelltorecognizethat the drop m a y be modified to a certain extent by moving the pallet stones, close to one or the other side, in the slots, as there is always some room allowed for the shellac which is used for holding the stones. The moving of the pallet stones in or out in the slots will also affect the draft feature of the escapement; this is a point which we should bear in mind whenever we make a change in the position of the pallet stones. The effect from moving the R stone o u t is to increase the draft on both stones, whereas if the L stone is moved out and the R stone in, it will decrease the draft. In order to ascertain that the escape wheel is correct, the lock and the drop should be tried with every tooth in the wheel onbothpalletstones. Thisshouldbedonewiththebankingsadjustedclose,soastojust permit the teeth to drop. And the best way to t r y this, is to move the balance slowly with the finger while the pallet action is observed through the peep holes. After completing the adjustment of the pallet action, the jewel p i n action is n e x t to be considered. The fork should swing an equal distance to each side of the center line when the pallet is banked to drop. If we find that it moves farther on one side than on the other, it will be necessary to bend the fork close to the pallet a sufficient amount to bring it in line. This is called, “ t o adjust the let-off.” The test for the let-off is to see that when the pallet is banked to drop, the jewel p i n is just as close to the corner of the fork, in passing out, on one side as on the other. This test is correct, provided that the fork is of equal length on both sides of the slot, as it should be. The test for the fork length is that is should allow the jewel p i n to pass o u t on both sides when the pallet is banked to drop. This is the maximum 29 length which is allowed for the fork. The test for short fork is to move the balance so as to unlock the pallet, then reverse the motion and see that the pallet is carried back safely to lockby thejewelpin. Thisshouldbetriedon both pallet stones. It is,however,cus‐ tomaryto trytheshakeof the fork when the center of the jewel pin is opposite the corner of thefork,andnotto allowthepalletto unlockfromthisshake. In orderto ensure perfect freedomin thejewelpinaction,thejewelpinshouldbefrom.01to .015 mm. smaller than the slot in the fork. The safety action is also adjusted, while the escapement is banked to drop. The guard p i n should be made just barely free from the roller when the fork is against the banking, and this should be tried carefully on both sides. If this is done cor‐ rectly, the roller will have the necessary clearance when the bankings are opened to allow for the slide. The operation of moving apallet stone is one that requires agreat deal of experience before one is able to do it satisfactorily except by repeated trials. Special tools called “pallet warmers” have been devised for holding the pallet during this operation. In the simplest form this tool consists of a small metalplate, about aslarge asa 12size barrel, with a wire handle by which it is held while it is heated. This plate should have one or m o r e holes drilledin it as clearance fOr the pallet arbor. An improved f o r m of this tool is shown on the following page. This tool is provided with a spring clamp for holding the pallet to the plate. The pallet is placed top side down against this plate, and the whole of it is warmed over the alcohol flame until the shellac is softened so the stones can be moved. A good way of applying shellac for the fastening of pallet stones is to w a r m some stickorbuttonshellac,overaflame,andpullit outin longthreadsofabout.5mm. diameter. Shellac in this form is very convenient to use, as it is only necessary, when the pallet is heated to the proper temperature, to touch the end of this thread to it at the place where the shellac is wanted. With a little practice one can learn to deposit just the right amount. After the pallet is cold,allshellac on the surface should be cleaned off carefully with a scraper made of brass or nickel. THE JEWEL PIN ACTION The fork and jewel pin action involves two distinct functions: the impulse and the unlocking. In order to illustrate and make this statement clear, we will consider the different parts of the escapement in a normal position, as shown on page 34, Fig. 1. The hairspring, controlling the balance, has brought the fork, by means of the jewel pin, to the normal position of rest. This leaves the pallet in a position where the impulse face of an escape wheel tooth will engage the impulse face of one or the other of the pallet stones, in this instance the R stone. Assuming the parts to be in this relation to each other, it is evident that when power is applied to the escape wheel,the escape wheel tooth,which is engaging the R stone, will cause the pallet to t u r n on its pivots, and this impulse is transmitted to the balance by the fork acting on the jewel pin. The impulse being completed, the escape tooth drops off from the R stone, and the second tooth forward comes to lock on the L stone, with the fork resting against the banking, as shown on page 36, Fig. 3. The fork slot is n o w in such a position that the jewel p i n m a y pass o u t perfectly free, and this condition is necessary because the impulse which was given to the balance imparted to that member acertainmomentum,causingit tocontinuetoturninthatdirectionuntilthismomentum is overcome by the tension of the hairspring. During this part of the motion, which takes place after the impulse, the jewel pin leaves the fork entirely, but the instant that the momentum in the balance is overcome by the tension in the spring, the balance will start to t u r n in the oppositedirection, the tendency of the spring being to bring the jewel p i n to the center line. Before reaching this point, however, the jewel p i n has to perform the very important function of unlocking. At the completion of the impulse we left the fork resting on the banking, with the fork slot in such position that the jewel p i n passed out perfectly free, and, figuring on the assistance of the draft and the safety action, which will be explained later, we are justified in expecting that the jewel p i n shall pass in to the fork slot perfectly free. The instant the jewel p i n has entered the slot, and comes in contact 35 DOUBLE ROLLER ESCAPE‐ MENT with the fork, the work of unlocking begins. And here is to be noticed, that for every tick of the watch, the pallet and fork is started from the condition of rest,by a sudden blow of the jewel pin. And not only the pallet is started,butthe whole train has tobestarted in the reverse direction, against the power of the mainspring, to unlock the escape wheel, in order to receive another impulse. The impulse on the L stone being completed, the pallet assumes the position shown on page 22. The jewel p i n passing o u t on an excursion, the same as on the other side, returns to unlock, receives a new impulse, and so on, at the rate of 18,000 times per hour. In viewof the above,it is evident that lightness,as far as it is consistent with strength and wearingquality, is an essential feature in the construction of the several parts. It was once considered necessary to attach a counterweight to the pallet,in order to get it in poise,b u t with the modern light construction of pallet and fork, it has been proven beyond a doubt that the ordinary form of counterpoise was worse than useless, inasmuch as it involved an added mass of metal whose inertia m u s t be overcome at each vibration of the balance. 38 THE SAFETY ACTION The function of the safety action is to guard the escapement against unlocking from sudden shocks, or outside influences, while the jewel pin is out of engagement with the fork. In the lower grades of watch movements this guard duty is assigned to the edge of the table roller and the guard pin. The passing hollow, a small cut in the edge of theroller,directly outsidethejewel pin,allowstheguardpintopassthecenterlineduring the jewel pin action. This form of safety action is called “single roller” and is shown in plan and elevation on opposite page. As will be'seen from this drawing, the edge of the roller is made straight, or cylindrical, and the guard p i n is bent in such a way as'to present a curved portion to the edge of the roller. The advantage gainedfrom this construction is that the guard pin can be adjusted forward or back by simply bending it at the base, withoutitsactionbeingin anywayafiectedbyareasonableamountofendwisemovement Fig.1 I ! I SINGLE ROLLER ESCAPE- \ . MENT 40 of either the balance staff or the pallet arbor. The double roller escapement, Figs. 3 and 4, page 36,presents a more desirable form of safety action;for two reasons: first, the inter‐ section of theguard pin with the roller is much greater, making it perfectly safe against catching, or wedging; second, any shock, or jar, causing the guard pin to touch the roller, will have less effect on the running of the watch, because the impinging takes place on a smaller diameter. The diagrams, Figs. 5 and 6 on the opposite page,illustrate the above statements. Thewedgeactionoftheguardpin,whenitisbroughttotheroller,isrepre‐ sented by the lines C and D, which are at right angles to the lines A and B, thus forming tangents to the points of contact. It will be seen that with the single roller this wedge is 17°, whereas in the double roller.it is 30°, a very considerable difference in favor of the double roller. SAFETY ACTIONS Fm5 ‐‐ -‐ 5//VGLE 304LEI? Fig. 6 DOUBLE 5041m 41 DIRECTIONS FOR PUTTING THE ESCAPEMENT IN BEAT An escapement is said to be in beat when it requires the same amount of power to start the balance in one direction as in the other. This should be tried with the main‐ springonlypartlywoundup,byarrestingthemotionofthebalancewitha pointedobject held between the heads of two balance screws, and allowing the balance to move slowly, first in one direction and then in the other. If it appears to require more power,in order to let off on one side than the other, it is said to be “ o u t of beat,” and it should be corrected by turning the hairspring collet a certain amount, on the balance stafi, until it takes the same amount of power to let off on one pallet stone as on the other. This is usually done without removing the balance, by reaching in over the top side of the hairspring with a special tool made of small steelwire and flattened at the end soas to enter the slot in the collet. Great care should, however, be exercised in doing this work, so as to avoid bending the hairspring o u t of true. 44 TIME AND TIMING See the minutes how they run! How many make the hour complete, How many hours bring about the day, How many days will finish up the year. (Henry V I ) One revolution of the earth on its axis in relation to a fixed star has, on account of its perfect uniformity, been adopted as the standard for the measuring of time. We are told that three barleycorns make an inch, and that the distance from the Equator to the North Pole is very near 1,000,000,000 centimeters. But we know, positively, from the calculations of the eclipses that one revolution of the earth is made in exactly the same lengthoftimenowas2100yearsago,atleast,within72,0partofasecond. Sothehow]‐ ogist m a y feel justly proud of having such a perfect standard for his work. And about him, it might be said, without exaggeration, that he is hitching his ideal to a star. The time occupied by the earth in making one revolution on its axis, in relation to a fixed star, is called a sidereal day, and is about §%,'§ shorter than a mean solar day. This difference is caused by the earth’s travelling around the sun once a year, in what might be called the same direction asit revolves on its axis. This, from our point of view, makes the sun lose one round in every 366, as compared with the fixed stars. True sun time is the time occupied by the earth in making onerevolution on its axis in relation to the sun,‐that is,frommiddaytomidday,asthesunpassesthemeridian. Thedurationoftheseintervals vary duringtheyear,because theearth’s orbit aroundthesunisnot circular, but elliptical, with the sun in one of the foci. The earth travels faster when it is in the part of this orbit which is nearest the sun, on accountof the greaterattraction of that body, and the varia‐ tion of time during a year from this cause is as great as seventeen minutes plus or minus from mean time. Mean time is obtained by dividing a whole year in as many equal parts as the number of solar days it contains; and if we take one of these mean solar days 45 of 86,400 seconds for a comparison, the sidereal day is 86,164.09 seconds long, or exactly 3 minutes 55.91 seconds shorter than the mean solar day. To illustrate the general prin‐ ciples of timing, it m a y be of interest to first make a comparison between the balance in a watch and the pendulum in a clock, as both of them evidently perform the function of measuring, or beating, time. The pendulum, as we all know, requires no special spring to bring it to its center line, the perpendicular, as the force of gravity furnishes the necessarypowerfordoingthisworkin averyidealway. Whenapendulumisputin motion it makes a vibration in a certain interval of time, in proportion to its length, regardless of its weight, because the force of gravity acts on it in proportion to its mass. The length of a pendulum is reckonedfrom its center of suspensionto its center of oscillation, which latter point is located a short distance below the middle of the bob. If a weight is added above this point, the clock will gain, because it raises the center of oscillation and has the sameeffectonthetimekeepingasraisingthewholebob,which isequivalenttoashortening of the pendulum; but if a weight is added below this point, it has the opposite efiect, as it really lengthens the pendulum. Reasoning f r o m these facts we come to the conclusion that we can make a certain change in the rate of a clock in three different ways. For example, we m a y make it gain (1) by raising the bob, (2) by adding weight above the center of oscillation, and (3) by reducing the weight below that point. An interesting fact in relationto thependulum,whichmaynotbegenerallyknownamongwatchmakers,isthat its rate of vibration varies slightly with change of latitude, and also of altitude (that is, its height above the sea level),making a clock lose at the Equator and at high altitudes, and gain as we go nearer the sea level and the Poles. This is due partly to the distance from the center of the earth, which is greater at the Equator than at the Poles, and partly to the centrifugal force resulting from the rotation of the earth on its axis. Both these factors tend to make an object weigh less (on a spring balance), at the Equator than at the Poles, and also cause a change in the rate of a clock as stated above. In a table on page 92 is given the value of gravitation (g) and the length of a pendulum beating seconds (1) for a few principal points, and also formulas by which these factors m a y be calculated forany placeontheearthofwhichthelatitudeisknown. In viewofthesefactswemight state, as a fourth way of making a clock gain malthough n o t a very practical o n e ‐ to move it to a locality nearer the Pole. A balance is different from a pendulum in three fundamental points: first, it is poised; consequently the force of gravity has no effect on it, except-as it influences the friction on its pivots; second, the vibrations are controlled by a spring instead of the force of gravity; third, a weight (mass) added to a balance will always make it vibrate slower, provided it is n o t thereby p u t o u t of poise, and the retard‐ ing effect will be greater the farther the weight is placed away from its center. One difficulty encountered in the first a t t e m p t to make accurate timepieces was the variation in the dimensions of metals caused by difference in temperature. All metals, with the exception of a recently discovered alloy of steel and nickel (64parts of steel and 36of nickel), have the property of expanding with increase of temperature,‐- the different metals show‐ ing a somewhat different rate of change. As the length of the pendulum is the all‐ important factor in the timing of clocks, so also is the diameter of the balance and the length and resiliency of the hairspring in a watch. It is absolutely necessary to devise some means of compensating for changes in temperature before a reliable timepiece of eitherformcanbemade. Sofarasthisproblemapplies to clocks,themercurypendulum proves to be a very satisfactory solution, at least so far as accuracy is concerned. The bob of this pendulum is composed of one or more tubes of glass or iron, and these tubes are filled with mercury to a certain height. When of proper dimensions,the expansion andcontractionofthiscolumn of mercury raises or lowersitsmasstoexactlycompensate for the change in the length of the pendulum rod due to variations in the temperature. This method, although very satisfactory for clocks, cannot, of course,be applied to watches, for obvious reasons, but for this purpose we make use of the property of the metals alluded to above, namely, the difierence in the ratio of expansion in different metals. Brass, for example, expands more than steel from a given increase in temperature, so in m a k i n g a compensating balance it is common M S “ ‘ to use steel for the arms and the inside of the rim, and brass for the outside of the rim, the brass being fused to the steel, so as to make a perfectunion. Thisrimiscutoffin twoplaces, as shown in the illustration, so as to make each ” m y7//7[Jenny: half of the r i m free to bend, as it naturally will tend to do, as a result from any change of temperature. A number of holes are drilled radially through this bi-metallic r i m , and these holes are tapped to receive the balance screws. Usually about twice as m a n y holes are made in the r i m as the number of screws used in the balance;this is done to give opportunity for moving the screws in the final adjusting to temperatures. The object in using screws in the balance r i m is twofold: first, to provide the necessary weight (mass) in the rim, and second,to have this weight movable for temperature adjustments, as stated above. We will now understand from what has been said that when a compensating balance is exposed to a higher temperature, every p a r t of it expands, or grows larger, b u t as a result of the combination of the two metals in the rim, and the ends of the rim being freetomove,each halfof therimwill curveinward,carryingitsweighttowardsthecenter of the balance, and thus compensate for the lengthening of the arms and the weakening of the hairspring. If a balance is exposed to a lower temperature, the action will, of course, be in the opposite direction. Whenawatchistobeadjustedtotemperatures,itisrun24hours,dialup,in atem‐ perature of 90° F., and its rate compared with a standard. It is then r u n 24 hours, dial 51 up, in a temperature of 40°F. If it shows a gain in the 40° temperature, as compared with the running in the 90°, it is said to be under-compensated. This is remedied by moving some screwsnearer the free ends of the rim. This will,of course,result in a greater compensating effect,because the screws which we move nearer the ends of the r i m m u s t travel a greater distance in or o u t in relation to the center of the balance when the balance is exposed to changes of temperature. After the screws have been moved,the movement istried againthesamelengthof time,and soon,untilit runsthesamein bothtemperatures. When a screw is moved in one sideof the balance,it is,of course,necessarythat thecorre‐ sponding screw in the other side should be moved the same. A modern compensation balance, combined with a correctly proportioned steel Breguethairspring,which has been hardenedandtemperedin form, constitutea time-measuringdeviceof marvelousaccuracy. And the bi-metallic rim, hardened asthe Waltham balances are, soas to beperfectlysafe against distortion from ordinary handling, is certainly a boon to the watchmaker. Themeantimescrewsusedin theWalthambalancesfurnishanexcellent meansfor accurate timing, as two, on opposite sides, can be turned an equal amount in (making the watch r u n faster) or o u t (slower) without changing the poise of the balance. The following is the effect of one-half turn of two mean time screws: 18sizeand16size.............................4..............t2%secondsperhour 14size, 1897 Model, Colonial Series and 12size..................2%seconds per hour 6sizeRegular....................................H‘..........4 secondsperhour 0sizeRegularand1900-1907Model ............................3 secondsperhour Jewel Series ..................................................3%seconds per hour SOME HINTS MEASURING AS APPLIED TO WATCHMAKING The success of every undertaking depends largely on the ability to figure out and make practical plans, as well as to work correctly from plans already made. The cut and try method so; much used in the past is not well adapted to our line of work in this scientific age; we should accustom ourselves to speak in exact terms as well as to work correctly to given measurements. It is doubtless true that watchmaking is in greater need of exact and systematic measurements than any other trade, and it is also true,gen‐ erally,that the average apprentice to the watchmaking trade gets very little, if any, in‐ struction in the a r t of measuring. It is a very common idea that it requires expensive gauges and elaborate instruments to produce first-class work; but very many times we m a y have the essential things right before us without thinking how we m a y apply them. It is the object of this article to point o u t to the watchmaker, who wants to make things, how an ordinary micrometer, as shown in illustration, m a y be used for practically all kinds of measuring pertaining to our trade. We have t w o kinds of measurements to consider: linear and angular. Linear meas‐ urements apply to the diameter, thickness and length of the different parts, for example: plates, wheels, pinions, pivots, mainsprings, etc. And angular measurements apply to the construction of wheel teeth andpinion leaves, and especially to the designing and making of the escapements. On account of the small dimensions of our work,it is convenient to use a small unit for our linear measurements. The Metric system is very practical in this respect, using the millimeter, which is about 1513 of an inch (exactly .03937”), as a unit, and subdividing the same into 110 and 150 mm. The fractions we usually write in decimal form, for example: 4.30 m m . instead of 4130 mm., and 5.76 m m . instead of 5170“0 mm., etc. T h e s c r e w i n t h e modern m i c r o m e t e r s h a s a p i t c h o f % m m . , s o o n e t u r n i s d i v i d e d into 50parts, in order to measure 15,mm., and, consequently, we must turn the screw t w o complete t u r n s for one millimeter, and the second t u r n should be read 55, 60, 65, etc., instead of 5, 10, 15. To avoid mistakes in the beginning, in reading the micrometer, it isadvisabletouseastraightscale,asshownin illustration,toverifytheresult. The micrometer here shown indicates 3.51 millimeter. The square scale verifies the 3.5 millimeter; the micrometer shows the extra .01millimeter. Beside this,the only thing for the beginner to learn,in order to use the micrometer successfully for linear measurements, is to use as light a touch as possible in applying the same to the objects which are to be measured. The u n i t for angular measurements is the degree, which equals 33,0 p a r t of a circle. The degree is subdivided into sixty minutes, and the minute into sixty seconds. And instead of writing the words “degrees,” “minutes” and “seconds,” the symbols °, ’, ”, have been adopted; so in order to denote one and one-half degrees we write 1°30’. Right here it m a y be well to point out the error very common among watchmakers, which is to speak about linear measurements, such as the diameter of the pivots and thick‐ ness of mainsprings, etc., as so m a n y “degrees.” This is entirely wrong, as such measure‐ ments should always be stated in fractions of a millimeter or inch. To use the micrometer for angular measurements, it m u s t necessarily be used in an indirect way. In order to illustrate,we shall take an example of making a club tooth escape wheel for a regular lever escapement. Let us assume that we have a complete draw‐ i n g of the escape wheel, drawn carefully to scale, for example, 20 or 50 times actual size, with the necessary measurements and angles marked on the same, somewhat like illustration. In looking over this, we find that we have four principal measurements to look o u t for, viz., the diameter of the wheel, the length of the clubs, the angle of the impulse faces and the angle of the locking faces. We will now first consider the gauges necessary for making those measurements correctly, before we begin the cutting of the wheel. Forthispurposeweturnoutofbrasswire,aplug,asrepresentedin illustration,withthree difierent diameters, of which the largest equals the diameter of the escape wheel, the next largest equals the circle which tangents the impulse faces, and the smallest equals the circle which tangents the locking faces. The length measurements of this plug are of no importance. I_ Ix I_‘l ll-l.{‘-o+‐‐ w'\ $ . o o _ -‐‐nll‐.50>l F‐ ____/2.00nun. _,| We next take a round piece of sheet steel, for example, a saw blank about .6 m m . thick, which we can hold in a step chuck and turn a hole in its center to fit perfectly the brass plug on its largest diameter. To this steel plate wefasten with screws two straight thin pieces of steel which may be made from a mainspring. On these pieces, the side which we are going to use as straight edge, m u s t be turned up as straight and square as possible. For locating these pieces on the circular plate we p u t the brass plug in the hole with the shoulder of the largest end flush with the plate, and place the piece A with the straight edge againstthe plug and screw it to the plate, asshown in illustration on page 62. Next we t u r n the plug end for end and fix the pieceB against the smallest end of the plug on the same side of the plate but on the opposite side of the hole from the piece A. At thepointCwemakeasmallclearancecutin thecircular plate for convenience in looking at the work. If we have followed these directions carefully, wehave now a gauge by which we are able to determine the angles of the impulse faces and locking faces, aswell asthe diameter of the wheel, by placing it over the wheel, as shown in c u t on page 64. A convenient gauge, or standard, for the length of the clubs,is shown below. This is made from a round steel wire about 1 m m . in diameter and70to80mm.long. To assistusin makingtheslot the correct width,we turn up a pivot or plug which we can measure with the micrometer and use that as a 5; standard for the slot. If we use adjustable calipers, instead of this gauge shown in cut, we should set them to the plug standard referred to above. An escape wheel made according to the dimensions given in c u t on page 59will fit in a Waltham 16 size movement, model of 1899. 331535 03 The Waltham Watchmakers’ Gauge, shown in the illustration on page 66, by its simple construction unites accuracy and strength, and is very useful at the bench. The d i a l i s g r a d u a t e d t o r e a di n o n e h u n d r e d t h s o f a m i l l i m e t e r , a n d i s i n t e n d e d f o r fi n e m e a s u r e ‐ ments, such as pivots, screws and staffs. These gauges are adjusted with great care, and are finished copper bronze, or gray sand blast surface. They can be procured through watch material jobbers, or from the Material Department of the Waltham Watch Co. The price for the Watchmakers’ Gauge (one dial) is $2.00 each net. Dennison N0. Waltham Thickness Dennison VValtham Thickness Dennison in Centimeters No. in Centimeters N o . Waltham Thickness in Ccntimeters Dennison No. Waltham Widths Dennison in Centimeters No. Waltham Widths in Centimeters Dennison No. Waltham Widths in Centimeters TABLE SHOWING THICKNESS OR STRENGTH OF MAINSPRINGS ........................... . , .250 TABLE SHOWING WIDTH OF MAINSPRINGS ...................................... .400 410 .420 .430 440 450 460 384..4....,.......i..4..,.... 470 ‘..i...i......,.. ...................................................... ...................................................... ...................................................... ..................................................... ...................................................... ...................................................... ...................................................... 260 270 280 290 300 310 320 330 350 33 ...................................................... ...................................................... ...................................................... ...................................................... ...................................................... 42 360 .370 .380 .390 .i...i,.4i4....i.......... 31‘..4.,......4 ....i........4 32.......4.., ......4,........ 37. ,.i...i...........i....... 34..4.... 35.......‘.... 36..i..4........i 41.4.....i,.‘.. .4.‘.....,.... 43..i.,..4,4...... ......4.,.. ..i...4....i..i.... ......‘...4...4 i.....,...., 4............i..,i......4 39.4..i..4.i.4. 40........................... .480 .490 500 .510 .520 ....44i....... 67 68 CaN‘sgue 2200-A 2200‐13 2200 2201 2202 2203 2204 2205 2206 2207 2208-A 2208‐B 2208-C 2208 2209 2210 2211 2212 2213 5 . . . 20 20 18 18 18 18 18 18 18 18 16 16 16 16 14 14 14 10 10 Model lstSer.1862 2d Ser. 1862 1859 Old Style '57 New Style ’57 1877 1879 1883 K. W. 1870 S. W. 1870 32331 “25235335 .270 .255to .260 .315 .295 to .300 .310 .285to .290 .310 .285 to .290 .310 .285 to .290 320 .290 to .295 .270 .250to .255 .320 .295 to .300 .255 .230 to .235 .275 .250 to .255 .248 .230 to .235 .248 .230to .235 .248 .230to .235 .248 .230to .235 .240 .225to .230 .225 .205to .210 .270 .250 to .255 .225 .205to .210 .250 .230 to .235 “i“ké‘iiiiiiefepr'é“ .020to .021 .020 to .021 .020to .021 .021 to .022 .021 to .022 .021 to .022% .021to .023 .021 to .022% .021 to .022 .021 to .023 .020 to .021 .021to .022 .020to .021 .021to .022 .020to .021 .021to .022% .021 to .022 .019to .020 .019 to .020 $2552.11. "$35,225“ LIST OF WALTHAM MAINSPRINGS 1860 1862 1868 1872 1870 1874 1884 58.42 23 60.96 24 58.42 23 58.42 23 58.42 23 53.34 21 53.34 21 53.34 21 53.34 21 53.34 21 53.34 21 53.34 21 53.34 21 53.34 21 53.34 21 48.26 19 48.26 19 48.26 19 48.26 19 » lstSer.1861 2d Ser. 1861 Catalogue N 0 . Size Model Barrel D e p t h .250 .205 .185 .205 .300 .220 .170 .170 .345 .300 .230 .230 .300 .170 .300 .185 .170 .220 Width of Spring in Centimeters .230 to .235 Thickness_of Spring in Centimeters Length in Centimeters Length in Inches 2214 2215 2216 2217 2218 2219 2220 2221 00 1891. 2222 18 1892 .020 to .021 to .016 to .018 to .018 to .012 to .012 to .014 to .015 to .018 to .021 .022 .018 .020 .020 .016 .016 10 8 and 6 1 and O 1874 1873 1882 and 1887 1889 1888 Regular Regular 48.26 40.64 40.64 40.64 63.50 40.64 16 40.64 16 36.83 14% 63.50 25 57.15 22% 48.90 19% 48.90 19% 57.15 22% 34.29 13% 63.50 25 38.10 15 26.04 IOM 38.10 135 6 16 6 .195 .175 .195 .285 25 0 2223 14 1895 2224 12 1894 2224‐A 12 1894 .015 .020 .019 .016 .016 .019 2225 2226 2227 2228 2229 2230 14 1895 J. S. 1898 16 1899 0 1900 10 L 0 1907 .012 to .012 to .018 to .010 to .013 .015 to .019 .010 to .013 .008 to .011 .011to .014 LIST OFWALTHAM MAINSPRINGS‐Continued .190 to .170 to .190 to .280 to .205to .210 .150to .155 .150 to .155 .325to .330 .280to .285 .215 to .220 .215 to .220 .280 to .285 .150 to .155 .280 to .285 .170 to .175 .150 to .155 .205 to .210 19 16 16 16 A FEW SHOP KINKS AND REMINDERS A PROPER METHOD FOR CLEANING A WATCH MOVEMENT After the movement is taken apart remove the balance jewels, and also the escape and pallet arbor jewels ( i f these parts are cap jeweled). Before taking these out, however, we should see if the settings of the hole jewels are marked for position, and if they are n o t marked, we should make a small dot near the edge:of each setting so they can be replaced correctly after the clean‐ ing. The following is the order in which {so/ME ®O QC -OP4LLET ®o “ BfllflNCE Q \, these settings are marked in Waltham movements. In the lower plate they are marked,asshown in the illustration. ecu © The balance and the escape jewels on the sides away from the pallet, and the pallet arbor jewel on the side towards the center of the movement. In the top plate all the jewels are marked on the side towards the center of the movement. After this has been attended to, p u t all the parts (except the balance) in benzine,toremoveoilandgreasymatter. Aftertheoiliscleaned off, s t r i n g a few pieces a t a t i m e o n a w i r e loop, o r hook, a s shown in the illustration, and wash in hot water with a medium soft brush and castile soap. While the p a r t s are on the hook, dip in a solution of cyanide of potassium(see directionsformaking, page 78) for one to two seconds; rinse thoroughly in clean water, immerse in alcohol for about ten seconds, and dry in warm box‐ wood sawdust. When the mainspring is taken o u t of the barrel, it should be handled carefully, and no attempt made to straighten it out. If the oil on it appears gummy, it should be cleaned off thoroughly with benzine, but if the oil appears good, it is better to only wipe the spring with a piece of cloth by folding it around the spring and sliding it along without straightening the spring. After the spring is p u t back in the barrel, which, by the way, should be done with a good mainspring winder, it should be oiled with good quality watch oil in sufficient quantity to insure thorough lubrication without risk of spreading on the outside of the barrel. The escapement jewels, after going through the benzine, should be taken, one at a time, with a pair of specially prepared tweezers, to avoid their snapping away, and held against a flat board, or a large piece of cork, and brushed thoroughly, one side at a time, with a fine tooth-brush dipped in alcohol. After the brushing, dip the jewel in clean alcohol, and dry between linen cloths. After going through this process, we are reasonably sure that the jewels are clean, but werecommend, to make it absolutely sure, a careful rubbing with a piece of pegwood, which has been pointed so as to go through the holes, and also one which is specially shaped for rubbing the cups in the jewels. After the jewels and endstones are p u t back in the plates, but before the movement is p u t up, the cap jeweled holes should be oiled. This is an operation which should be done with utmost care, as it is very important to give the right quantity of oil. The consequence of too much oil at these points is almost as bad as lack of oil. For the purpose of retaining a sufficient a m o u n t of oil in the pivot holes, we take advantage of a natural phenomena,which is called capillary action. This action is, roughly stated, the tendency of liquids to r u n in between surfaces which are nearly in contact, and also to r u n upwards,quite rapidly,in verysmall tubes, against the force of gravity. The capillary action is strikingly illustrated in the wick of a lamp in which the close proximity of the fibres to each other, acting like capillary tubes, causes the oil to runupwardsthroughthewickasfastasitburnsatthetopendofit. Inviewofthese facts, and by the aid of the drawing below,we shall endeavor to explain why sometimes apivotwillrundryinashorttimebecausewegavetoomuchoilinthepivothole. Look‐ i n g at the drawing we find that the hole jewel is convex on the side towards the endstone, and also that there is a certain distance between the two jewels. This space is usually made about .02 to .03 m m . , and is for the purpose of providing a reservoir for the oil. And the convex shape of the hole jewel tends to keep the oil around the pivot, being attracted by the close space nearest the hole, by virtue of the capillary action referred to y / ‘ Q Z W above. Now,if weshould give so much oil that m arm it would fi l l the space to the edge of the hole jewel, it would immediately be attracted by the close space between the settings, which would pull it away and leave the pivot without a reserve supply of oil. The oil between the jewels ought to show in the proportion indi‐ cated on the drawing, or nearly so. For applying the oil we recommend an oiler made of small wire, about .40 m m . diameter, preferably gold, which is filed, tapering almost to a point, and the end flattened by hammering. This flattened point will hold the oil in a fairly definite quantity, so we know how much we deposit in the hole. After the oil has been p u t in the cup of the jewel, if it does n o t r u n down, we should coax it to do so by inserting the point of a pivot broach, and not consider the job done until we know by inspection that the oil has filled in properly between the jewels. The cleaning of the balance with the hairspring requires special care, as it cannot be brushed safely. The usual method is to p u t it on a hook and dip it for a few seconds, first in water, then in cyanide; rinse in water, dip in alcohol and dry carefully in sawdust. The balance m a y be buffed afterwards with a string of chamois skin held in a wire bow, to brighten the r i m , as well as the screws. After the balance has been cleaned, it should be examined carefully for any minute fibre that might have caught in the balance screws, or particles of sawdust in the slots of the screw heads. When cleaning a balance, if the jewel pin is set with shellac, and also when cleaning pallets, care must be taken not to leave them in the alcohol very long, as it Would dissolve the shellac and loosen the jewels. After the movement is set up,all the rest of the pivots should be oiled and also the palletstonesortheescapewheelteeth. Butdonotoilthejewelpinorthesafetyaction. In the stem winding works,all the bearing surfaces should be oiled, including the square of the winding arbor where it r u n s through the clutch. Here it m a y be well to emphasize the importance of taking good care of the oil which we use. It should be kept in a dark and cool place, and we should put only a drop or two at a time in our oil cup. A small agatecupwithboxwoodcover,such asis furnishedbydealers in watchtools,isbestadapted for use on the bench. This should always be cleaned before putting in fresh oil, and cov‐ ered when it is n o t in use, to prevent contamination of the oil by dust, etc. The setting up of a full plate movement is often found difficult for a beginner, on account of the potance into which the fork must project. ment, 18size, Modelof 1883,is set up most conveniently on its pillar plate, by leaving o u t the pallet and fork untilafterweputon thetopplate,andraisingthe top plate on the pallet side,allowing it to rock on the t w o pillars on each side of the barrel, a sufficient a m o u n t to give r o o m for inserting the pallet and fork. The setting up of a Waltham 18 size movement, model of 1892, should be done on its top plate by using a block The Waltham Full Plate Move‐ like the one shown in cut, for holding the plate. The opposite side of this block is made tofit thepillarplateafterthemovementisturnedoverforinsertingtheplatescrews. These blocks are supplied to watchmakers by the Waltham Watch Company, free oi charge, on application. The best kind of alcohol for cleaning watch parts is commercial grain alcohol. We would n o t recommend using either denatured or wood alcohol for this purpose. The cyanide solution referred to should be made in the proportion of 7 ounces, avoir‐ dupois, to one gallon of water, and this solution should be renewed assoon as it shows a tendency to turn dark. Cyanide of Potassium is u virulent poison, and great care must be taken in handling i t . It is considered deadly if reachingan open scratch in the skin. The fumes should also be avoided. A good way of keeping both the cyanide and alcohol for cleaning watches is in one gallon specimen or candy jars, with ground glass covers, and marked with conspicuous warning labels. CASING Before putting a watch movement in its case, always oil the winding bar in the pendant, where it runs in the sleeve, to prevent rust and squeaking. See that the move‐ mentlinesup properlywiththewindingbarin thecase,soit willwindand backratchet freely. It is sometimes necessary to remove the winding bar and sleeve from the case pendant and enlarge the hole in it to one side or the other, with a round file, in order to get aperfectlyfree action. The length ofthe square onthe winding bar should also be looked after to see that both the winding and setting action is right. If the square is too long,it m a y be shortened by filing without removing it from the case. If it is too short,it is necessary to remove the crown and turn in the sleeve n u t until the action is right. See that the crystal does not touch the center, and that the hands clear the dial and the crystal, as well as each other. After the case is closed,hold the watch to your ear and listen if the balance pivots will “ b u m p ” clear on both endstones, as they should do, when the watch is tipped from side to side. This will indicate if the case in any way interferes with the freedom of the balance. TO REMOVE A BROKEN SCREW FROM A WATCH PLATE After all other screws and steel work are removed,suspend the plate on a copper wire in a saturated solution of alum in water. If the screw whichisto beremovedis very long it is necessary to take the plate from the solution every twenty-four hours, and with a sharp point remove the dissolved steel, in order to hasten the action of the solution. HOW TO SET A JEWEL IN A WATCH PLATE To replaceabrokenjewelwhichissetdirectlyin theplate,first,carefullyremoveall the pieces of the old jewel, m o u n t the plate with the hole true in a pump center jeweling head, or a universal head. R u n the lathe slowly, and with a pointed burnisher carefully open the old bezel u n t i l the sides are parallel, and the diameter about the same as the originalsize. If thebezelismadeanylargerthanthe originalsize,it isvery likely to break. Theusualwaytoputthenewjewelinplaceistowettheendofthefingerandtouchit to the jewel which will adhere readily. Push it into the setting and slide the finger off. This will leave the bezel and the jewel wet, and hold the jewel while the bezel is being closed over it. The form of tool used for burnishing down the bezel is shown in Fig. 1,page 82. This tool is held firmly on the T rest at the proper height, the beveled side toward the hole, as 81 shown [in Fig. 2. With the lathe running slowly, it is forced toward the plate until the bezel is closed firmly over the edge of the jewel as in Fig. 3. If the bezel is broken, a jewel of the same outside diameter as the original one m a y sometimes be set securely by making a new bezel of larger diameter and burnishing it in far enough to cover the edge of the jewel. This is done by starting the burnisher at a point fartherawayfromthejewel,thanshowninFig.3,page82. If themetalaroundtheholeis cutawaytosuchanextentthatthismethodisimpracticable,it willbenecessarytoeither select a jewel of larger outside diameter, or p u t a metal bushing in the plate large enough to make a new setting of the diameter required for the new jewel. 84 MAINSPRING DON’TS Don’t fail to provide yourself with the best mainspring winder that can be obtained. See that the hooks on all arbors of the winders are no longer than the thickness of the thinnest spring,andthusavoidkinking,and,therefore,unnecessarybreakingofmainsprings. Don’t use a mainspring that is too long, because it fills the barrel and prevents that part, or the mainwheel, from making the required number of revolutions, with the con‐ sequence that the watch will n o t r u n as long as it should after each winding. Don’t use a mainspring that is too strong, because it will set, increase the chances of breakage and injure the watch. Don’tuse a mainspring that is too wide, and be sure that the tip and brace do not extend beyond the limits of the cover and barrel. Don’t forget that a mainspring should n o t occupy more than one-third the diameter of the barrel, thus leaving two-thirds to be divided between the arbor and winding space; to enable the watch to r u n about thirty-six hours. Don’texpectamainspringtobeflatifyouputitinthebarrelwiththefingers. This methodusuallyinjuresthespring,'givesit aconicalform,andtherebyincreasesthefriction in the barrel. Don’t bend the inner or outer end of the mainspring with flat-nosed plyers, but pro‐ vide yourself with specially made round-nosed pliers which will give a circular form to these parts, prevent short bends, contract the inner coil, and thus secure a closer fit to the barrel arbor without injuring the spring. Don’t expect other than a properly fitted flat mainspring with rounded edges to produce the least friction in the barrel, allow the greatest a m o u n t of power to the train, and give the best results as to time, service, etc. Don’t expect a mainspring to always endure extreme changes in temperature, or electrical disturbances, or straightening at full length, or neglect from lack of cleaning and oiling. Don’t expect a watch that needs cleaning or other repairs to run satisfactorily by merely putting in a new mainspring. Don’t expect a mainspring to plough through too much dirt. HINTS AND SUGGESTIONS Make it a rule to test every watch y o u handle for magnetism. A small pocket com‐ pass placed close to the balance when the watch is running will indicate by a vibrating motion if the balance is polarized, and, if it is, the watch should be treated, case and all, in a de-magnetizer, to remove this trouble. When repairing a watch inspect the balance pivots carefully, to see that they are straight and in good condition. Examine the endstones, and if they show any wear, it should be polished off, by using a small lap made of tortoise-shell about 30 m m . in diam‐ eter, mounted in the lathe, and a small a m o u n t of fine diamond powder mixed with oilputon thefaceof it. By holdingthepittedendstoneagainstthiswithaslightpressure, while the lap is running at a fairly high speed, it can be made as good as a new one in a very short time. After this operation,it is important to clean the endstone and setting thoroughly. 88 Examine the balance to see that it is true and in poise. (As containing directions for truing and poising a balance, we wish to recommend a very excellent article on this subject in a book issued by Kendrick 69“ Davis, Lebanon, N. H., entitled “Book of Tools, No. 6.”) Do n o t open the bankings carelessly. Remember that the result of excessive slide is a dead loss of power, and this loss increases rapidly with any deterioration of the oil on the pallet stones. Do not neglect to try the jewel pin to see if it is set firmly. _Even a slightly loose jewel pin is a fruitful source of trouble. Do not open the curb pins on the regulator. The hairspring should fit between the pins, without pinching, and without play, to get the best result in timing. See that the hairspring is centered and flat, and has a sufficient amount of clearance under all conditions. Bear in mind that its regular vibrations will be increased a good deal at times, when the watch is subjected to sudden motions or shocks. Do n o t neglect to remove any finger mark or greasy matter on the plates, caused by the handling of the movement. For this purpose, we find a buff stick very useful,‐ a flat stick of wood, about 14m m . wide, covered on one side with buckskin, such as is used for buffing. The end of this is dipped in benzine, wiped off rapidly with a clean cloth, and used immediately for cleaning off the top surface of the plates. Do n o t expecta position adjusted watch to rate the same as it did originally after any change or alteration has been made in the balance pivots, or balance jewels. Even when the work is done with the greatest care,this kind of repairs m a y call for readjusting the movement, and this should be done by a watchmaker experienced in this classof work. Do not consider it a bad investment to put asmuch money asyou can afford into up-to-date tools. And do n o t consider the time wasted which you spend in keeping your tools in good condition. 90 Do n o t neglect to keep abreast of the times by reading good books and papers per‐ tainingtothetrade. At thesametime,bemindfulofthefactthatyoucannotlearnwatch‐ making from books or by correspondence only. We wish to emphasizeto the young watchmaker the importance of practice or train‐ ing in the various branches of his work; and would recommend, as a profitable way of spendingsomeof hisleisuretime,to take,forexample,adiscardedbalance,andbendit out ofshape,andtrueandpoiseit repeatedlyforthepurposeof gainingexperience. Wemight state that although a beginner m a y work on a balance all day, and still n o t succeed in getting it in very good order, an expert can do 20 to 25 in an hour, and get them all good. This applies equally well to the work on the hairspring, the escapement, the pivots, jeweling, andsoon. Andwe wishtosayin conclusion,thatnothingbuthardworkandconscientious application to the work, coupled with a certain a m o u n t of study, will ever bring forth a skillful and efficient workman. WALTHAM SCREW TAPS The following table gives the pitch, the diameter of the thread and also the proper size of the tap drill, for all the screws used in the Waltham Watch movements. Taps of all these sizes are furnished by the Company at a nominal price. N o . of ' T a p 3 5 7 0 11 13 15 17 19 ’220 21 240 23 254 N o . of Threads to an inch 110 Diameter of Thread on Screws in Millimetcrs 1.50 1420 1.10 1.00 .93 1.34 1.00 .83 .65 .55 .45 .35 Diameter of Drill in Millimctcrs 1.32 1.02 .95 .85 .71 1.22 .85 471 .54 .45 .34 .27 110 120 140 160 170 180 180 200 To find which is the right tap for any of the screws used in Waltham Watch move‐ ments, measure the diameter of the screw and refer to the table. If the screw measures .65 for example, we find that .65 in the column of diameters of threads corresponds to No. 17tap, for which the tap drill should measure .54. ' The only threads which we are unable to identify by measuring their diameters are No.7andNo.13,butinthisinstance thedifference inpitchissufficienttoshowataglance in comparing one with the other. 91 The Equator Washington, D. C. New York Greenwich 5 Stockholm The Poles 1 ° 3 Latliltude 1 ’ g. 978.10 979.35 980.04 980.21 980.60 981.17 981.83 983.10 L o g . g. 9903833 . 9909379 9912447 9913190 .9914919 9917443 .9920363 2.9925977 1. L o g . L 99.102 1 9960835 99.229 1 . 9966381 99.299 1.9969449 99.316 1 . 9970192 99.355 1 . 9971897 99.413 19974432 99.481 1 . 9977401 99.609 19982479 ¢=latitude. g=value of gravitation in ( t m s . The effect on a pendulum from change of latitude of one degree amounts to from a fraction of a second, near the Equator,to4sec.‐|‐in24hours. Thefollowingfiguresare in round numbers, at the sea level. Between Washington, D. C., and New.York (1° 50') 8 sec. in 24 hours. Between Washington, D. C., and Montreal (6° 7') 24 sec. in 24 hours. Between New Orleans and Montreal (15°) 55 sec. in 24 hours. Between Equator and Poles (90°) 3 min. 44 sec. in 24 l=lengthincms.Ofapendulumbeatingseconds. T=time in seconds. g=977.989 (1+0'0052 sin 21°) I ' 2 . = 2 . = ‐~ g=(‐T‐) ' l g( T) ’ T ”J 1 7: T: n= 3.14159265 Log. 77: = 0.4971499 (L)2 7T = 0 . 101321 Number of seconds in 24 hours=86,400. Log. 86,400 =4.9365137. g Log.(_1_)2 =0.0057002 72' USEFUL NUMBERS ooooo 4 / 123456789 ‐M,Ll,mm 1o10 a0 2 1o60 70257025 799o92/94 11356 4837261594327/5o¢85 99 71 /: 57 0 80 TABLE OF EQUIVALENTS, MEASUREMENTS OF LENGTH. INcH 7654521 HO |Mzrzn[Nat-INC” L/c/vss o5 a o00 n 060 omo I/l222 2 5 7 ao 0 2 a 3 II 7 ICENTHV£‘r£fi=/5319éflouzEI M E ; 9 0000 3456739 T369258/47 cal ENGL M/LL/Msrifi 735 fiflLL/ PrchH ”www $2;70 M u m s a0 5 o 74/852763 371 0123¢567370 IDOUZEME=JN879JCENfMHWffi IZ n = /Pfiflvch'LIG/VE 125456739 an aoaoaO.O/ 00 a o 89 77 5 % HAIRSPRING CURVES Any shape of an outer terminal curvemade in conformity with Phillip’s theory is called a Phillip’s overcoil. An illustration of a hairspring supplied with a theoret‐ ically correct outer terminal, commonly known to watch‐ makers by the name of Overcoil, such as used at present in all Waltham movements, is shown here. As is well known to watchmakers. hairsprings are sup‐ plied with overcoils to secure a concentric action of the hair‐ spring while the balance is.in motion. A concentric action of the hairspring is necessary, in order to reduce the position error as much as possible. This result is partially obtained when a hairspring is supplied with a theoretically correct outer terminal or overcoil, whereby the center of gravity of the outer half of the hairspring is made to coincide with the center of the balance at every stage of its vibration. In other words, probably plainer to every watchmaker, we havepoised the outer half of the hairspring in a scientific way. There are other ways of poising a hairspring, but no more scientific way known to us at present. In a watch fitted with a hairspring with an outer terminal curve only, there still remainsa position error,part of which,at least,is due to the fastening of the inner end of the spring, which, in its ordinary form, tends to throw the spring o u t of poise during its vibrations. This the Waltham Watch Company has succeeded in overcoming by making hairsprings with theoretically correct inner terminal curves. This inner curve maintains the body of the spring in perfect poisewith the balance, during both its opening and closing vibrations. We show here an illustration of a hairspring of this kind with inner and outer terminals both, hardened and tempered in form. Hairspringsof this kindareusedat present in the higher grades of Waltham 16 size movements. It will be obvious to every thinking watchmaker that we have thus in a thorough and scientific manner removed all position errors due to erratic action of the hairspring. 95 Taper Shoulder Balance Staff ....................... 4 HairspringStud ..................................6 SpiralWindingPinionandC.W....................7 Sapphire Jeweled Mainwheel ....................... 8 Recoiling Click ...................................10 Taper Steady Pins ................................12 Pendant Setting Mechanism........................13 The Size ofaWatch Movement ....................14 Lever Escapement ................................15 Pallet Action ...............................i.19 Roller and Jewel Pin ..........................25 Time and Timing .................................46 MeasuringandGauges .................‘...........56 VVatchmakers’Gauge ............................68 Mainspring Tables ................................69 Shop Kinks and Reminders: How toClean aWatch ........................72 Lasing.......................................81 Removing Broken Screws ......................82 How toSet 3.Plate Jewel ......................83 Mainspring Don’ts ...........................86 Hints and Suggestions ........................89 Waltham Screw Taps ..............................93 Matching Jewel Pin Action Useful Numbers ..................................94 Safety Action Putting Escapement in ................... ....................................27 .............................. ................................ 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