| 0113 1723 AVA l i | il | UNITED STATES PATENT AND TRADEMARK OFFICE —— ' << SC 2 — : Se < oe — es oN tts” dC SE . Oe . e A TREATISE ‘FI CONSTRUCTION AND USE —or— UNIVERSAL AND PLAIN GRINDING MACHINES, CYLINDRICAL AND CONICAL SURFACES, AS MADE BY BROWN & SHARPE MFG, Co, * PROVIDENCE, R.I. U.S. A. FINE MACHINERY AND MACHINE TooLs, Loss PROVIDENCE, R.I. BROWN & SHARPE MAFUFACTURING COMPANY. 1891. Entered according to Act of Congress, in the year 1691, by BROWN & SHARPE MFG. CO., In the Office of the Librarian of Congress at Washington. PREFACE, Our chief desire in publishing this Treatise is to assist the - novice in becoming familiar with the construction and use of Universal and Plain Grinding Machines. A complete description is given of each of the machines, although they have a number of features in common, for repetitions are here less objection- able than the annoyance and possibility of misunderstandings occasioned by frequent reference from one machine to another. To the descriptions we have added a number of suggestions in regard to the care and use of the machines and a number of examples showing their adaptation to different kinds of work. We also have included in the book a few pages on the measur- ing tools advantageously used by those operating Grinding Machines. BROWN & SHARPE MFG. CO. et REAR VIEW OF NO, 1 BUILDING. CONTENTS. Introduction Descrivrion of No, 1 UNIVERSAL GRINDING MACHINE. Wase, Bed, Sliding Table, Swivel Table... sss. eee eeseee ence eens Adjusting Screw and Scale for Tapers, Wheel Bed, Wheel Slide. . Wheel Platen, Wheel Stand, Wheel Guard, Feed Motion...... ‘Cross Feed, Head Stock. . ‘Foot Stock, Wheel Spindle and Boxes, Driving Pulley on Spindle * Wheel, Speed Counter for Internal Grinding. . yee Grinding, Pump, Overhead Works, Brake, Location of Counter “Shaft, Speed of Counter Shaft, Hangers.....+-..-.e0e + seaierahens Capacity of Machine, Attachments and Accessories.........+.+ tees _Desentrrion or No.2 UNIVERSAL GRINDING MACHINE. Stand, Bed, Sliding Table, swivel Table, Adjusting Screw and Scale for Tapers... ee. cece cere scene cette etter eee e nen e eee eee es Wheet Bed, Wheel Slide, Wheel’ Platen and Stand, Wheel Guard, Feed Motion.......- Cross Feed, Head Stock Foot Stock, Whcel Spindle and Boxes. . Driving Pulley on Wheel Spindle, Pulleys for Internal Grinding, Wet Grinding, Overhead Works. . Brake, Location of Counter Shaft, Speed of Counter Shaft, Hangers, Capacity of Machine, Attachments and Accessories. .....++.++00++ Description oF No, 2 PLain GRINDING MACHINE, Stand, Bed, Sliding Table, Wheel Slide and Stand, Wheel Guard,... Feed Motion, Cross Feed, Head Stock, Foot Stock.......... eens en Wheel Spindle and Boxes, Overhead OW OLkS tactic ie. site ee: Brake, Location of Counter Shaft, Speed of Counter Shaft, Hangers, Capacity of the Machine., Attachments and Accessories. .. 27 28 31 34 36 37 38 39 4o 4u 42 43 6 BROWN & SHARPE MFG. CO. DescripTION oF No. -2 UNIversat GrinDiInG MACHINE, IMPROVED. Base, Bed, Sliding Table Swivel Table, Adjusting Screw and Scale for Tapers, Wheel Bed. 4 Wheel Slide, Wheel Piaten, Wheel Stand, Wheel Guard, Feed Motion. Cross Feed. . Head Stock. Foot Stock, Wheel Spindle and Boxes. Driving Pulley on Wheel Spindle, Extra Spindle for Internal Grinding, Overhead Works, Brake... ce. eee eee cere teen eens Location, of Counter Shalt, Speed of Counter Shaft, Ifangers, Wet Grinding, Capacity of the Machine.,........-.- seeees tence Machine to take go!’ between'Centres. Attachments and Accessories. Description or No. 3 ‘Uxiversat GrInDING MACHINE." Bed, Table, Adjusting Screw. and, Scale for Taperse.-..eseesee eres Wheel Bed, Wheel Slide, Wheel Platen, Wheel Stand, Wheel Guard, Feed Motion...... Cross Feed, Head Stock Foot Stock, Wheel Spindle and Boxes. sor Driving Pulley on Wheel Spindle, Wet Grinding, Overhead Works... Brake, Location of Counter Shaft, Speed of Counter Shaft, Hangers, Capacity of the Machine.........- Attachments and Accessories......+ oe INTERNAL GRINDING FIXTURE. MATERIAL, WORKMANSHIP, ETC... ..ceeeeee eee desig oaiais Se apa Care anp Use or MACHINES. Oil and Oiling, Cleaning Adjusting Spindle Boxes, End Motion of Spindle, Pump. . Emery Wheels, Selection and Use: Coarseness or Fineness, Softness or Hardness, Width of Face, Speed of Wheel... - Speed of Work, Accurate Grinding. . Grinding Long or Large Pieces. .... Water, Internal Grinding, Summary. Truing and Mounting Wheels, Removing Wheel from Spindle, Direc- tion in which work should run......eeeee eres cet teeeenereses 49 95 BROWN & SHARPE MFG. CO, 7. Lapping, True Centre Holes, True Face Plates. . 96 Grinding Tapers. + 96 Driving Work on Centres, Advantage of Grinding on Dead Centres, Grinding Straight Work.......- 6- see ees ee eens sauna anes. OF EXAMPLES OF GRINDING. Plain External Grinding, Use of Back Rest Plain Grinding with Wheel on End of Spindle. . Plain Internal Grinding, Grinding External Tapers. - Grinding Two Tapers with one Setting, Grinding Spindle and Box, Grinding Internal Tapers... 1.0... cece ee er renee eet ee nee se. 102 Squaring Ends of Bushings, Odd Work, Grinding Work on Head Stock, Truing Centres, Disk Grinding.......- Use of Centre Rest, Use of Special Chuck, Grinding Cutters "aad Reamers..- 1-0 eee even eee neceeee Seog eeeeseeeene seeeeevees TLO SPECIAL GRINDING MACHINERY...---+-. ++ pidhs Se autiieewigiaes’ 118 GAUGES AND CALIPERS. Standard Caliper Gauges, Standard Cylindrical Gauges.........+++- 119 Standard Internal and External Cylindrical Gauges, Standard Refer- Disks, Caliper Squares, Vernier Calipers.......- tose oe 122 Micrometer Calipers. .. . Limits allowed. ....... . Ceevecoenee +e 129 Method of Reading Micrometer Caliper, Limit Gauges, Catalogue... 131 Table of Decimal Equivalents of Fractions of an Inch......-+s++++ 132 Table of Decimal Equivalents of Fractions of a Millimeter. « 133 List of Wheels. .scsccccescscsects coeasesseescasons 8 : BROWN & SHARPE MFG. CO, FIG. 1. No. 1 Universal Grinding Machine. BROWN & SHARPE MFG. CO. 9 INTRODUCTION. The introduction of high-speed machinery, and the demand for increased accuracy in machine construction in general of to-day, call for machines which are better adapted to produce uniform surfaces and accurate work than the lathe and the planer of the past. It is well-known, to all engaged in the manufacture of machinery and tools of precision, that the lathe is incapable of producing accurate work, even in the softer metals, and in operating upon hardened surfaces it fails us altogether. It is very important to have journals and other wearing surfaces smooth and true when they are made. They cannot be depended upon to “wear to a fit’ as formerly was sometimes erroneously supposed, If they are imperfectly made, the tendency is to become worse by wear. In high-speed machinery heating of journals is often caused by imperfect fitting. In fact, we may say that the success of high-speed machinery depends very largely upon our ability to do better work than we have been able to produce on the lathe. The only successful field which seems to be open to us, at the present time, to meet this want, is to use the lathe as a roughing tool, or machine to bring the work approximately to the desired size, then to finish by grinding with emery wheels on a suitably designed machine. To meet this want in our own works, a number of years ago, we designed and constructed grinding machines which have proved to be very useful, in fact indispensable, for the production of first-class work, They have become necessary and economical tools in the manufacture of special and general, as weil as standard, machinery and tools. In duplicating parts of small machinery, manufactured on the interchangeable system, such as sewing 10 BROWN & SHARPE MFG. CO. machine shafts, needle bars, etc., they are unexcelled. They are especially useful, as they can be used to operate on hardened as well as soft work to produce the same degree of accuracy, excellence and economy, Without the use of suitable grinding machines the introduction of hardened spindles and boxes into lathes, milling machines, drilling machines, etc., etc., would be impossible, and the, value and desirability of such improvements, in machine tools will not be disputed. By grinding such work as crank pins, valve rods, piston rods, etc., of locomotive and other steam engines, a vast improvement can be made in the quality and durability of the same, as well as a great saving in the.cost of prodution, The fact that it cos¢s /ess to finish and fit work by grinding with emery wheels, than it does by the old way on the lathe, has been proved repeatedly by experience. The saving is in the cost of files, emery paper, etc., as well as in the “ime it takes to do the work. ‘This is true for all kinds of work, whether the grinding is done for making accurate fits, or simply for the sake of finish or polish. The fact that work can be done more accurately on a grinding machine than on a lathe, is also. well sustained by experience, As an example of the guadity of work that can be done on these machines, we may refer to the standard gauges which we manufacture, some of which are illustrated in the latter part of this ‘Treatise, In the want of something better than the lathe and the planer to produce accurate work, frequent attempts have been made in various shops to rig up an emery wheel attachment to lathes and planers, for the purpose of grinding such work as crank pins on the former, and cross-head guides on the latter, but, as might be expected, these would usually give unsatisfactory results, from the fact that these machines were not adapted to produce the quality of work wanted. ‘The simple application of an emery wheel to an article will not improve its character unless the grinding machine is designed for, and adapted to, the kind and quality of work wanted. In doing fine work, defects will fre- quently appear which would never be noticed in a coarser class ; hence it is that a planer, or a lathe, may be well adapted to a certain class of work, but when we demand something better BROWN & SHARPE MFG. CO, It from it than that for which it was designed, we shall invariably be disappointed. The grinding machines, as built by us, are the outgrowth of our own experience in the business of manufacturing. We have, therefore, had ample opportunities, for a number of years, to study the needs and requirements which would adapt them to the use for which they are intended. We are now building them with all the improvements made during the past years of experience. The Universal Grinding Machines were designed to do a general class and large variety of work, such as may be required in a general jobbing shop. For this kind of work they are well adapted, though they are equally applicable to ordinary manu- facturing purposes. For manufacturing ona large scale, however, plain or special machines may be more desirable. Each of the regular machines indicates by its dimensions and capacity the class of work for which it should properly be used. It may’ be but just to those into whose hands this Treatise may. fall, as well as to ourselves, to state in this connection that the machines which we describe herewith and which we exhibit more in detail than is usually customary, are protected by letters patent issued in 1877, 1885 and 18go. 12 BROWN & SHARPE MFG, CO. FIG, 2. No. 1 Universal Grinding Machine. REAR VIEW. BROWN & SHARPE MFG. CO. Description of No. 1 Universal Grinding Machine. The perspective views, Figs. 1 and 2, give a general idea of the No. 1 Universal Grinding Machine. The design is well adapted to resist vibrations within the machine itself—an element essential to the durability of the machine and the accuracy of its work, The base rests upon three points or feet and is fitted as a closet for the tools and accessories used about the machine. The bed and base are cast in one piece and the sliding table moves upon the bed on one V and one flat slide, as shown in Fig. 3. The ways are lubricated by two rolls in each, Thus the oil is equally distributed over the bearings and the proper position of the sliding table is maintained, a feature of some consequence in 13 General Construe- tion. Base. Bed and. Sliding Table. accurate grinding. The waste oil from the mechanism | in the bed can be drawn off through a pipe from the bottom of the bed. The shallow basins or pockets, one at each end of the sliding table, form convenient places for wrenches and other tools in frequent use about the machine, and the dust caps beyond the basins protect the slides when the table travels to its extreme movement. These caps are curved so that weights cannot conveniently be placed at the extreme ends of the platen. The head and foot stocks are mounted upon a swivel table, which rests upon the sliding table and turns on acentral stud. The line of centres accordingly can be set at any angle with the table slides, for the purpose of grinding tapers without throwing the head and foot’ stock spindles out of line—see Fig. 22. When Swivel Table. 14 Adjusting Serew aud Seale BROWN & SHARPE MFG. CO. set to any desired position, the swivel table is clamped for heavy work at each end to the sliding table. In ordinary work, however, the weight of the table gives sufficient stability, so that clamping is not required. For setting the table accurately to grind any desired taper an adjusting screw is provided and a for Tapers. scale graduated to show the taper both in degrees and in inches per foot. The graduations marked “ Taper in inches per foot,” give the whole taper of the work, and those marked “ Degrees,” give the taper from the centre line of the work or one-half the whole taper, which is the angle the swivel table is set out of line. By this arrangement very exact settings can be easily obtained, The T slot extends the whole length of the table and receives the heads of the clamp bolts, by. which the head and foot stocks are secured. The slot is scraped to.a straight edge and the tongues of the head and foot stocks are carefully scraped to fit the slot. The head and foot stocks may be set at any point on the platen, which is a convenience in using the machine for a variety of purposes. Wheel Bed. The wheel bed is supported by the rear-ward pro- Wheel Slide. jection of the base, shown in Fig. 2, which extends to the floor and stands directly upon one of the feet of the base, A semi-circumference at the lower edge of the wheel bed is graduated to degrees so that it may be set at any desired angle, in a horizontal plane, relative to the sliding table. When properly set it is clamped by a bolt on each side of the standard, The wheel slide moves on wide, flat bearings and is held in place by a 45 degree gib. ‘his and the forward projecting dust cover completely protect the slides from dust. The wheel platen rests on a flat, circular bearing, the mean diameter of which is greater than the distance between the bearings of the wheel spindle. A steady support for the wheel stand is thus provided and rock- ing is prevented. BROWN & SHARPE MFG. CO, 15 Fig. 3, 16 Wheel Platen. “Wheel Stand, Wheel Guard. Feed. Reversing. BROWN & SHARPE MFG. CO. The wheel platen may be set in any position, and is held in place by a bolt on each side, The object in having the wheel platen swivel is to enable the operator to bring the face of the wheel parallel with the line of travel of the wheel slide as shown in Fig. 46. In internal grinding the wheel platen is turned around, a speed counter is used in place of the wheel stand, and an internal grinding fixture is placed on the end projecting over the swivel table, as shown in Fig. 4. The wheel stand is secured in any position on the wheel platen by two 7 bolts, ‘These, with the two bolts in the wheel platen, and the two bolts in the wheel bed, form a rigid connection with the heavy rearward pro- jection of the base. The wheel guard is bolted to the wheel stand. It shields the operator from sparks, dust and water, and is sufficiently heavy to protect him in case of accidental breakage of the wheel. The feed is engaged by pushing a knob in the cen- tre of the hand wheel on the front of the machine. The connection is positive, and cannot become accidentally disengaged. When desired the table can be moved by the hand wheel. The motion of the table is automatically reversed by a lever, which is actuated by dogs that can be set at any position the same as the dogs on a planer. For very delicate adjustment of the length of stroke requisite in grinding up toa shoulder, etc., the lever car- ries a patented device. The lever and its adjoining parts are cushioned by a simple arrangement, so that the table is reversed without shock or jar—an im- portant feature in accurate grinding. By raising the device on the lever the path is cleared for the reversing dogs when it is desirable to move the table beyond the reversing point for trying work. This convenient ar- rangement preserves the adjustment of the length of stroke, and at the same time allows any length of move- ment of the table by hand. By simply dropping the device down upon the lever, the machine will continue SES STS Fats Sooo nea aE SET STTETETE FER ESS a eR SOR Se er TT BROWN & SHARPE MFG, CO, 18 Cross Feed, Head Stock. BROWN & SHARPE MFG, CO. reversing as before, The wrench and nuts which secure the dogs in place are made in one piece, and are always in position, The cross feed by which the emery wheel is brought against the work to be ground, is operated from the front of the machine by a hand wheel graduated to read to thousandths of an inch. The wheel is fed smoothly, whatever may be the position or angle of the wheel stand, wheel platen or wheel bed, and the universal features of these parts are extremely advantageous in grinding large tapers, either external or internal. The head stock shown in Figs. 5 and 6 is fastened to the table by a clamp screw and swivels upon a central pin. Its whole circumference at the lower edge is graduated to degrees so it can be set at any desired position, The spindle is made of tool steel, and the bearings are hardened, ground and lapped. ‘The boxes are phosphor bronze. ‘Their material makes it possible to run the spindle when they are tightly clamped upon it, and this clamping is necessary to obtain perfect face and hole grinding. The clamping adjustment is simple and positive. Wear is taken up by screws A, The screws B limit the extent to which the box can be closed, and should be loosened before taking up the wear by the screws, 4. The end thrust is taken by a shoulder on the spindle, and adjustment for wear is made by a nut at the rear end of the spindle. The thread on the forward end is not cut up to the shoulder, but a bearing is left so that chucks and fixtures can be made to run truc within a very smail limit, This bearing and the taper hole are ground when the spindle is in place, The spindle is made fast for dead centre grinding by a thumb screw. ‘The head stock is provided with a pulley for driving the spindle and with smail and large dead centre pulleys. Work may thus be ground in a chuck or fixture on the head stock spindle, or upon two dead centres, or upon AEE SR Ear Sa BROWN & SHARPE MFG. CO. fom ! rng eer 20 Foot Stock. BROWN & SHARPE MFG, CO. one dead and one live centre. The advantage of grind- ing work upon two dead centres is that any possible im- perfection in the spindle bearings does not affect the accuracy of the grinding. The foot stock, shown in Figs. 7 and 8, is secured to the swivel table by a clamp screw. The spindle is quickly operated by a lever, and the work is held between the centers by a stiff spring. By this arrangement the spindle adjusts itself to the varying length of the work caused by expansion, and the pressure between the cen- tres remains substantially constant. An oil reservoir is provided for oiling the centres. Both head and foot stock spindles are hollow. Wheel A section of the wheel stand and spindle is shown . Spindle and, Boxes, Driving Pulley. Speed Counter. in Fig. 9. he spindle is steel, hardened, ground and lapped. The end play is taken up with the nut A; Bis -the check screw. Provision is made for delicate adjust- ment. The boxes are 3 inches long, and 7% inches in diameter, They are made of phosphor bronze, are self-aligning, and may be adjusted by the nuts Cand D. Both nuts are turned towards the back of the machine to take up the wear, and the boxes with the spindle can be removed from the wheel stand without disturbing the adjustment of the boxes. An effort has been made to prevent vibration in the wheel. ‘The bearings can be run metal to metal, and the wheel stand and adjoining parts are firmly connected with the rigid base of the machine. The driving pulley and the flange are made in one piece, the pulley being 234 inches in diameter, It is fitted to the taper arbor at /, and held in place by the nut J. A special speed counter is furnished for internal grinding, as indicated in connection with Fig. 4. The belt from the overhead works to the speed counter should be crossed. Our patented Internal Grinding Fixture is used on this machine. 2L i BROWN & SHARPE MFG. CO, BROWN & SHARPE MFG, CO. 22 6 OLE Y. LES J EJ BROWN & SHARPE MFG. CO. 23 Provision is made for wet grinding. The pumpis | Wet asimple fan revolving in a loose case, and has connec- Snednk: tions for distributing the water either upon the wheel or upon the work. The overhead works consist of three shafts with Overhead tight and loose pulleys 8-inch diameter for 3-inch belt, Wo™* The shafts should run in the direction indicated by the arrows, Figs, 10 and 11, and are arranged for six speeds between 2,002 and 3,400 forthe emery wheel, and for six speeds between 93 and 640 for the work. The drum shaft is driven by a 11-inch belt, the emery wheel by a 14-inch belt, the feed cone by a 1-inch belt, the head stock spindle and dead center pulley by a 1-inch belt, and the pump by a 1-inch belt, The motion of the emery wheel is controlled by the main belt shipper, while that of the work is con- ° trolled independently of the wheel. By this means work can be changed on the center or chuck without stopping the wheel, This saves time and allows the wheel to be in full motion when starting to grind. That no time may be lost in waiting for the work Brake. to stop revolving after it is ready to be removed from the machine, a friction brake is connected with one of the shipperrods. When the clutch is released the brake is applied, and the work may be stopped almost instantly. The relation of the counter-shaft to the machine is Jocation . + f Counter shown in Figs. 10 and rr. Shaft. A copy of a large scale drawing with figures giving prawing, the correct location of the most important parts of the counter-shaft is sent with every machine, The speed of the counter-shaft should be about Speed. 280 revolutions per minute. The hangers are provided with self-adjusting and Hangers. self-oiling boxes. BROWN & SHARPE MFG, CO. 24 BROWN & SHARPE MFG, CO. 25 The machine will swing work between centres 8 Copaclty inches diameter and 16 inches long, while the table May Machine. be fed several inches beyond that length. The swivel table will swing to either side of its central position to grind tapers from zero to 1% inches per foot, or from zero to 3% degrees in angular measure. For grinding work on the face plate or chuck, the head stock can be set at any angle within the whole circle. The wheel slide has a movement of 4 inches, and may be fed at any angle from zero to go degrees on either side of a line at right angles with the slide bed. The wheel stand will take a wheel 7 inches diameter and ‘thick with a 2-inch hole in centre. The internal grinding fixture usually sent with this machine will grind holes 5 inches long, and 34 inch and upwards in diameter. Wheels not larger than 1 inch in diameter are used with this fixture. The weight of the machine boxed ready for ship- ment is about 2600 pounds. The floor space measured over extreme projections and points of travel of the various parts is 36x69 inches. Each machine is provided with a drawing showing Attach. location of overhead works, copy of this treatise, an "Auces internal grinding fixture, a special speed counter for se internal grinding, a 3-jawed chuck, special chuck for thin cutters, centre rest, back rest, wheel truing stand, tooth rest, large and small dead centre pulleys, centres, pump, wrenches, dogs and complete overhead works, fad 26 BROWN & SHARPE MFG. CO. FIG. 12. No. 2 Universal Grinding Machine. | 1 | ; | | BROWN & SHARPE MFG. CO, 27 No, 2 UNIVERSAL GRINDING MACHINE. The perspective view of the No. 2 Universal Grind- sone ing Machine, shown in Fig. r2, gives an idea of its tion, general form and outward appearance. Figs. 13 and 14 give a general idea of its construction. The stand is made in the form of a closet with stand. shelves on each side of the door, These shelves are cast in the stand and serve to give stiffness as well as to form convenient receptacles for tools and accessories. The bracket, Z, is designed to support a water pail to receive the waste water during the process of wet grinding, : The bed, 7, is made in box form, and well braced by Bea. cross ribs. Upon the bed the sliding table, G, slides on one VY Sliding and one flat slide, as shown in Fig. 14. At each end Table. of the table is a shallow basin. These form convenient places to receive wrenches and other tools which are in frequent use about the’machine. They also serve to protect the slides when the table travels to its extreme movement. The head and foot stocks are mounted upon a Swivel swivel table, Z, which turns on a central stud. This ™ allows the line of centers to be set at an angle with the table slides, for the purpose of grinding tapers, without throwing the head and foot stock spindles out of line— see Fig. 22. When set to any desired position, the swivel table is clamped by a bolt at each end to the sliding table. For the purpose of setting the swivel table to grind any desired taper, it is provided with an adjusting screw, and a scale accurately graduated tore se show the taper, both in degrees and in inches per foot. and Seale The scale marked, “TAPER IN INCHES PER FOOT, gives for Tapers 28 ‘Wheel Bed. Wheel Slide. Wheel Platen, ‘Wheel Guard. Feed. BROWN & SHARPE MFG. CO. the whole taper of the work and the scale marked “DEGREES” gives the taper from the center line of the work, or one-half of the whole tager, which is the angle the swivel table is set out of line. The T slot extends the whole length of the table and receives the heads of the clamp bolts, 4, O, Fig. 13, thus allowing the head and foot stocks to be set at any point in reference to its length. The Z slot is scraped to a straight edge, and the tongues of the head and foot stocks are scraped to fit the slot, Upon the knee, Z, Fig. 14, is mounted the wheel bed, Q, which may be turned in a horizontal plane, and asemi-circumference at the lower edge is graduated to degrees so it can be set at any desired angle relative to the sliding table, When properly set it may be clamped by bolts to opposite sides of the knee. The wheel slide, 7, slides on V gibs, one attached on each side to the wheel bed. One of these gibs is made adjustable for the purpose of taking up sis play which may be caused by wear. ‘The wheel platen, V, is fastened to the wheel slide by a screw, which allows it to be set at any angle in reference to the table slides, The two 7'slots, Y, Fig. 13, receive the clamp bolts which secure the wheel stand, Z, to the platen, The wheel guard is bolted to the wheel stand, and serves to protect the operator from sparks, dust and water, as well as from flying pieces of emery in case of accidental breakage of the wheel, It also forms a con- venient terminus for the water tube which conducts the water to the work in wet grinding. The general arrangement of the feed gearing will be seen in Fig. 14. The feed may be operated either automatically or by hand, and is engaged by tightening the nut, B,. The motion of the table is regulated and automatically reversed at any desired point by the dogs which shift the reversing lever, Q,. The table is moved by hand with the crank wrench. _ BROWN & SHARPE MFG, CO, 5 29 BROWN & SHARPE MFG. Co. BROWN & SHARPE MFG. CO, The feed worm is provided with an oil cellar, A, from which oil is constantly supplied to’ it by a small disk wheel, revolved in the oil by the worm itself. The other gears are conveniently oiled from above by moving the table endwise out of the way. These do not require so much oil, as their motion is slow compared with that of the worm. ‘The cross feed, by means of which the emery wheel is brought against the work to be ground, is operated by the crank wheel. As previously stated, the wheel bed, Q, swivels, and the feed will work smoothly whatever may be the position or angle to which the wheel slide, 7, and the bed, Q, may be set. This uni- versal feature of the cross feed is extremely advantage- ous in grinding large tapers, both external and internal, &, is an adjustable dog fitted to the periphery of the crank wheel. This, with the studs, S,, 7, forms a con- venient stop to prevent accidentally forcing the wheel into the work being ground, and thus damaging one or the other, or both. ‘The head stock shown in Fig. 15 is attached to a base plate which is bolted to the swivel table of the machine. It is clamped to the base plate by two bolts, the heads of which are free to slide in a circular Z'slot. It is made to swivel about a central pin, and its whole cir- cumference at the lower edge is graduated to degrees so it can be set at any desired angle. The spiadle is steel, and the bearings are hardened, ground and lapped. The driving pulley is placed be- tween the uprights. The boxes are phosphor bronze, and fitted to the bearings, Their material makes it possible to run the spindle when they are tightly clamped upon it, and this clamping is necessary to obtain perfect face and hole grinding. The clamping adjustment is simple and positive. " The end thrust of the spindle is taken entirely on the forward bearing, and is conveniently adjusted by check nuts with fine threads. The spindie projects ge Crosse Feed. Head Stock. 3: BROWN & SHARPE MFG, CO, BROWN & SHARPE MFG, CO, 33 Fig.16 Foot Stock, BROWN & SHARPE MFG. CO. through the rear dust cap to allow a bolt to be passed through its entire length to secure the work to the face plate when it is desired to true the periphery of a piece in which a hole is to be ground. A stop is provided for holding the pulley between the uprights and preventing the spindle from turning when work is to be revolved upon centres. The knurled nut serves to protect the thread on the spindle when the chuck or face plate is not in use. The caps inclose and protect the bearings from emery dust. The foot stock is clearly shown in sectional views in Figs. 16 and 17, ‘The spindle is provided with taper boxes, which may be adjusted to compensate for wear, by turning the dust caps, ?, and Q,, The spindle is operated with a lever, A,, instead’ of the usual screw, and the work held between the centres by a stiff spring. By this arrangement the spindle adjusts itself to the varying length of the work —due to the change of temperature caused by grinding—and the pressure be- tween the centres remains substantially constant. It also possesses the advantage of being operated more quickly than a screw. Large work, which is not ap- preciably affected by the heat, may be held more “securely, when necessary, by clamping the lever, Ra Wheel Spindle and Boxes, with the screw, 7’,. ‘I'he movement of the spindle, as well as the tension of the spring, can be regulated with the mut, Ug. At V3, is an oil reservoir for oiling the centres, Both head and foot stock spindles are hollow, hav- ing a half-inch hole through them for the purpose of removing the centres. A section of the wheel stand and spindle is shown in Fig. 18. The spindle is hardened, ground and lapped, and the end play is taken up with the nut, 4, 2 being its check screw. This provides for the delicate adjust- ments necessary in accurate grinding, The journals are 3 inches long by % inches diameter, and rua in bronze bearings which are self-aligning. : | 35 BROWN & SHARPE MFG. CO. 36 Driving Pulley. Small Wheel. Pulleys for Internal Grinding. Wet Grinding. Overhead Works. BROWN & SHARPE MFG, CO. They are adjusted by the nuts, Cand J, and turning both nuts towards the back of the machine takes up the wear. Thespindle and boxes can be removed from the wheel stand without disturbing the alignment of the spindle, and the spindle with the boxes can be turned end for end. Oil is supplied to the spindle by the felt, 7, which is supported by a spring. The driving pulley and flange are made in one piece. The pulley is 4% inches in diameter. This pulley is fitted to the taper arbor at J, and is held in place by the nut, /. A smaller emery wheel is used for backing off cutters, reamers, etc., as in Fig. 60, The shank for this wheel is fitted on the left hand end of wheel spindle. Two extra pulleys, 47 and Z, shown in Fig. 24, are fitted to the spindle to take the place of the emery wheel, and its pulley, when it is desired to do internal grinding. Our patented Internal Grinding Fixture is used on this machine. : Provision is made for wet grinding. The overhead works consist of a compound counter- shaft as shown by Figs. 13 and 14, with a back shaft, a forward shaft, and a drum_ shaft, in combination with the hangers, pulleys and shippers, substantially as shown. ‘The 3-inch main belt runs on 8-inch tight and loose pulleys on the back shaft, and is usually ar- ranged as shown, Fig. 14. It may, however, be driven from back of the machine, as shown by the dotted line, in which case the belt fingers must be extended back- wards and curved over the pulleys, as shown by dotted lines, In either case the shaft should revolve in the direction indicated by the arrow. All the belts connecting the shafts and machine should usually be open. The forward shaft is driven from the back shaft by a 2%-inch belt on tight and loose pulleys, ‘fhe drum shaft is driven from the front shaft by a 14-inch BROWN & SHARPE MFG. CO. 37 belt on the cone pulleys, with three changes of speed. The feed works receive motion from a three-step cone on the drum shaft through a belt 7 of an inch wide. ‘The emery wheel is connected with the back shaft from the large pulley by a r-inch belt. A ¥%-inch belt from the drum drives the dead centre pulley in grinding small work, while for other kinds of work the pulley on the head stock spindle is driven from the same drum by a 13-inch beit. The motion of the emery wheel is controlled with the main belt shipper, while that of the work is con- trolled, independently of the wheel, with the other shipper, By this means work can be changed on the centre or chuck without stopping the wheel. ‘This saves time, and is productive of good work, as the wheel is always in full motion when starting to grind. “That no time may be lost in waiting for the work Brake. to stop revolving after it is ready to be removed from the machine, a friction brake is connected with the rod of the shipper, so that when the belt is shifted from the tight pulley to the loose one, the brake will be brought up against the flange of the cone pulley on the front shaft. By this means the dram, and consequently the work, may be stopped almost instantly. The relation of the counter shaft to the machine Location should be such that, viewing the machine as in Fig. eriek 13, a plumb line from the centre of the middle shaft. hanger should pass 6} inches to the left of the centre of the machine. ‘I'he other hangers can then be located by the length of the shafts. A copy of a large scale drawing, with figures, giving Drawing. the correct location of the most important parts of the counter shaft, is sent with each machine. The speed of the counter shaft should be four speed. hundred revolutions per minute. The hangers are provided with self-adjusting and Hangers, self-oiling boxes. 38 BROWN & SHARPE MFG. CO, Capacity The machine will swing work between centres 12 of the inches diameter and 28 inches long, while the table Machine. =! may be fed several inches beyond that length. The swivel table, 7, Figs. 13 and 14, will swing to either side of its central position to grind tapers from zero to 2 inches per foot ; or, from zero to 5 degrees in angular measure. For grinding work on the face plate or chuck, the head stock can be set to any angle within the whole circle, The wheel slide, 7, has a movement of 5% inches, and may be fed at any angle from zero to 90 degrees on either side of a line at right angles with the sliding table G. The wheel stand will take in a wheel of 12 inches diameter, and %-inch thick, with a 5-inch hole in centre. ‘The wheel shank, shown at H,, Fig. 18, is adapted to 6-inch wheels, 36 of an inch thick, with a 34-inch hole. The internal grinding fixture usually sent with this machine will receive wheels up to 2 inches in diameter, and will grind 54 inches in length, and x inch and up- wards in diameter. The weight of the machine, boxed ready for ship- ment, is about 2,400 pounds. The floor space, measured over projective and ex- treme points of travel of the various parts, is 38x114 inches. Attach- Bach machine is provided with a drawing showing mentsand location of overhead works, a copy of this treatise, an Acces sories. internal grinding fixture, a 3-jawed chuck, special chuck for thin cutters, tooth rest, centre rest, back rest, face plate, dead centre pulley, wheel shanks for small wheels, centres, wrenches, dogs, and complete overhead works, i | BROWN & SHARPE MFG. CO, 39 No. 2 PLAIN GRINDING MACHINE. The general appearance of this machine is inmany General . Mie dive Construe- respects the same as the No. 2 Universal Grinding Ma- ~ tion, chine, Fig. 12. The stand is made in form of a closet with shelves Stand. on each side of the door. ‘These shelves are cast in the stand and serve to give stiffness, as well as to form’ convenient receptacles for tools and accessories. Over’ the door suitable slides’ are provided to receive an oil pan, which catches the drippings from the mechanism’ above, A bracket supports a water pail to receive the waste water during the process of wet grinding. The bed is made in box form, and is well braced by Bed and cross ribs. Upon the bed the sliding table rests and ae slides on one V and one flat slide. Shallow pockets or basins, one at each end/of the table, form convenient places to receive wrenches and other tools which are in frequent use about the machine. They also serve to protect the slides when the table travels to its extreme movement. The head and foot stocks are mounted upon the sliding table, and may be set at any point in reference to its length. ‘fhe knee supports the wheel slide and stand, which wheel ate cast in one piece, This slides on V_ gibs, one of Slide ani which is made adjustable for the purpose of taking a up any Jooseness that may be caused by wear. ‘The wheel guard is bolted to the wheel stand and Wheet serves to protect the operator from sparks, dust and Guard. water, as well as from flying pieces of emery in case of accidental breakage of the wheel. It also forms a con- venient terminus for the water tube which conducts the water to the work in wet grinding. 42 Feed, Reversing. Cross Feed. Head Ltock, Foot Stock. BROWN & SHARPE MFG. CO. The feed may be operated either automatically, or by hand, and is engaged by tightening a knurled nut on the front of the machine. The motion of the table is automatically reversed by the dogs, which shift the reversing lever. ‘Ihe travel of the table is also regulated by these dogs, as they can be set at any position, being fastened by bolts which are adjusted in a 7'slot the same as on a planer. The cross feed, by means of which the emery wheel is brought against the work to be ground, is operated by the crank wheel on the front of the machine, There is an adjustable stop fitted to the periphery of this wheel, which, with the adjoining studs, form a convenient arrangement to prevent accidentally jam- ming the wheel into the work and thus damaging one or the other, or both. The wheel moves only at right angles with the sliding table. ‘he head stock is clamped to the table, and can be set at any point upon it. The upper part swivels upon the base, and may be firmly clamped to the same. The spindle is provided with a pulley, which can be used either for driving the spindle or for driving the work upon dead centres. When work is driven on dead centres the spindle is locked to prevent its turn- ing. Means are provided to compensate for wear of the boxes and to take up the end play of the spindle. The head stock is marked for two positions, one to show when the spindle is in line with the foot stock spindle, and the other 30 degrees from this, to set the head stock for grinding centres. As it is difficult to set the spindle exactly in line by the graduations, means of adjustment are provided on opposite sides of the base plate. The foot stock is shown in Figs. 16 and 17. The spindle is provided with taper boxes, which may be ad- justed to compensate for wear. It is operated bya lever, and the work held between centres by a stiff spring. By this arrangement the spindle adjusts itself BROWN & SHARPE MFG. CO. tothe varying length of the work, due to the change of temperature caused by grinding, and the pressure between the centres remains substantially constant. It also possesses the advantage of being operated more quickly than a screw. Large work, which is not ap- preciably affected by the heat, may be held more securely, when necessary, by clamping the lever. The movement of the spindle, as well as the tension of the spring, can be regulated by a nut. An oil reservoir is provided for oiling the centres. Both head and foot stock spindles are hollow. The wheel spindles and bearings are the same as shown in Fig. 18, The spindle is hardened, ground and lapped, and the end play is taken up by a nut, which is provided with a check screw. The boxes are 3 inches long and 7% inches diameter. They are self- aligning and made of bronze, and can be adjusted to compensate for wear. Oil is supplied to the spindle from the receptacle below by a piece of felt which is supported by a spring. 41 Wheel Spindle and Boxes, The overhead works consist of compound counter- Overhead shaft, with back shaft, front shaft and drum shaft, in combination with hangers, pulleys and shippers, sub- stantially as shown in Fig. 14, The 3-inch main belt runs on 8-inch tight and loose pulleys, and is usually arranged as shown. It may, however, be driven from back of machine, as shown by the dotted line, in which case the belt fingers must be extended backwards and curved over the pulleys. In either case the shaft should be revolved in the direction indicated by the arrow. All belts connecting the shafts and machine should usually be open. The front shaft is driven from the back shaft by a 24-inch belt on tight and loose pulleys, The drum shaft is driven from the front shaft by a 114- inch belt on the cone pulley with three changes of speed, and the feed works receive motion from a three- step cone on the drum shaft through a %-inch belt. The emery wheel is connected with the back shaft from the large pulley by a 1-inch belt. A 34-inch belt from Works. 42 Brake. ‘Location of Counter Shaft. Drawing. Speed. Hangers. Capacity of the Machine, BROWN & SHARPE MFG. CO. the drum drives the dead centre pulley in grinding small work, while for other kinds of work the pulley on the head stock spindle is driven from the same drum by a 14-inch belt. The motion of the emery wheel is controlled with the main belt shipper, while that of the work is con- trolled independently of the wheel. By this means work can be changed on the centre, or chuck, without stopping the wheel. This saves time and is productive of good work, as the wheel is always in full motion when starting to grind. That no time may be lost in waiting for the work to stop revolving after it is ready to be removed from the machine, a friction brake is connected with one of the shipper rods, so that when the belt is shifted from the tight pulley to the loose one, the brake will be brought up against the flange of the cone pulley on the front shaft. By this means the drum, and consequently the work, may be stopped almost instantly. The relation of the counter shaft to the machine should be such that a plumb line dropped from the centre, Fig. 14, of the drum, will intersect the line of centres of the machine, Viewing the machine, as in Fig. 13, a plumb line from the centre of the middle hanger should pass 536 inches to the left of the centre of the machine, ‘The other hangers can then be located by the length of the shafts. A copy of a large scale drawing, with figures, giving the correct location of the most important parts of the counter shaft, is sent with each machine, The speed of the counter shafts should be about 4oo revolutions per minute, The hangers are provided with self-adjusting and self-oiling boxes. ‘The machine will swing work between centres 12 inches diameter, and will grind pieces 6 inches diameter and 18 inches long, while the table may be fed several inches beyond that length. | | i : : : . BROWN & SHARPE MFG. COQ, 43 The wheel stand has a movement of 5% inches, and will take a wheel 12 inches diameter and ¥% inch thick, with 5-inch hole in the centre. The weight of the machine, boxed ready for ship- ment, is about 2,000 pounds. The floor space, measured over projections and extreme points of travel of the various parts, is 38x96 inches. Each machine is furnished with a drawing showing Attach- location of overhead works, a copy of this treatise, mongent centre rest, back rest, centres, dogs, wrenches and sories. complete overhead works, 44 BROWN & SHARPE MFG, CO. FIG. 19. No. 2 Universal Grinding Machine, , IMPROVED. i BROWN & SHARPE MFG, CO, 45 No. 2 UNIVERSAL GRINDING MACHINE, IMPROVED, The perspective views, Figs. 19 and 20, give a (encral general idea of the No. 2 Universal Grinding Machine Sonera: Improved. The design is well adapted to resist vibra- tions within the machine itself, which is an indispen- | sable element for the durability of the machine and for accuracy in the work produced. The base rests upon three feet, and has an internal Base. web bracing. It is fitted as a closet, with shelves on each side of the door. The bed is made in box form and well braced by Bea cross ribs. From the bottom of the bed there is a descending pipe through which the waste oil can be drawn off, Upon the bed the sliding table moves on one Y_ Sliding and one flat way, as shown in Big. 21. ‘These bearings 7 are twice as large as in the No. 2 Universal Grinder, and are lubricated by two rolls in each, and the oil is thus equally distributed over the bearings, and the proper position of the sliding table is maintained,—a feature of consequence in accurate grinding. The sliding table is heavier than that of the No. 2 Universal Grinding Machine, weighing, with swivel table and head and foot stocks, 225 pounds more than the corresponding parts of that machine. ‘The shallow basins (one at each end of the table), form convenient places for wrenches and other tools in frequent use about the machine. The dust caps beyond the basins protect the slides when the table travels to its extreme movement, and, where accuracy is required, these basins should not be loaded with weights or heavy parts of machines, The caps are curved to prevent weights being placed at the extreme end of the platen. 46 BROWN & SHARPE MFG, CO. FIG. 20. No. 2 Universal Grinding Machine, Improved. REAR VIEW. BROWN & SHARPE MFG. CO, 47 Fig. 21. l N ai Gain 48 BROWN & SHARPE MFG. CO. Swivel The head and foot stocks are mounted upon a Table. swivel table, which turns on a central stud, and thus allows the line of centres to be set at any angle with the table slides, for the purpose of grinding tapers, without throw- ing the head and foot stock spindles out of line—see Fig. 22. When set at any desired angle, the swivel table is clamped at each end of the sliding table for heavy work. For ordinary work the weight of the table gives sufficient stability, so that clamping is not required. ‘Adjusting For the purpose of setting the table accurately foot to grind any desired taper, it is provided with Scale for an adjusting screw and a scale graduated to show the Tapers taper both in degrees and in inches per foot, ‘The scale marked “taper in inches per foot,” gives the whole taper of the work, and the scale marked “ de- grees” gives the taper from the centre line of the work, or one-half of the whole taper, which is the angle the swivel table is set out of line, By this arrangement very exact settings can easily be obtained. The T slot extends the whole length of the table and receives the heads of the clamp bolts, by which the | head and foot stocks are secured. ‘This slot is scraped to.a straight edge, and the tongues of the head and foot stocks are scraped to fit the slot. The head and foot stocks may be set at any point on the platen, which isa convenience in using the machine for a variety of purposes. Wheel ‘The wheel bed is supported by a rearward projec- Bed. tion of the base, shown in Vig. 20, which extends to the floor and rests upon one of the feet by which the base is supported. It may be turned in a horizontal plane, and a semi-circumference at the lower edge is graduated to degrees so that it may be set at any de- sired angle relative to the sliding table. When properly set it may be clamped by the bolts on opposite sides of the standard. BROWN & SHARPE MFG. co. 49 The wheel slide moves on wide, flat bearings, eight Wheel times as large as those of the No, 2 Universal Ma- ld chine, and is held in place by a 45 degree angular gib, which, with the forward projecting dust cover, com- pletely protects the slides from dust. The weight of the wheel slide, with its platen and stand, is 365 pounds ; corresponding parts on the other machine weigh 112 pounds. : The wheel platen rests on a flat circular bearing, wheet the mean diameter of which is greater than the distance Platen. between the bearings of the wheel spindle. A steady support for the wheel stand is thus provided and rock- ing is prevented. The wheel platen is held in place by a bolt on each side. The object in having the wheel platen arranged so that it will swivel, is to enable the operator to bring the face of the wheel parallel with the line of travel of the wheel slide as shown in Fig. 46. In internal grinding the wheel platen is turned around and the wheel stand is used as a speed counter— see Figs. 23 and 24, while the internal grinding spindle is placed on the opposite end of the wheel platen, which in this position projects over the swivel table and brings the wheel spindle into the proper position for grinding holes., The wheel stand is secured in any position on the whee wheel platen by two T bolts. ‘These, with the two bolts Stand. in the wheel platen and the two bolts in the wheel bed, form a rigid connection with the heavy rearward pro- jection of the base. The wheel guard is heavy and is bolted to the wheet wheel stand. It serves to protect the operator from Guard. sparks, dust and water, and is a safeguard in case of accidental breakage of the wheel. The feed is engaged by turning the knurled knob Feea at the right on the front of the machine. ‘Uhe connec- tion is positive. When desired the table can be moved by the use of the hand wheel, BROWN & SHARPE MFG, CO. 52 Reversing. Cross Feed. BROWN & SHARPE MFG. CO. The motion of the table is automatically reversed by a lever, which is actuated by the dogs on the front of the sliding table. For more delicate adjustment of the length of stroke requisite in grinding up to shoulders, etc., the reversing lever carries a patented device. This lever and its adjoining parts are cushioned by a simple arrangement, so that the table is reversed with- out shock or jar, a decided advantage, as any shock or jar in grinding machinery is detrimental to accurate work, The dogs can be set at any position the same as the dogs on a planer. By raising the device on the lever, the path is cleared for the dogs when it is desirable to move the table beyond the reversing point for trying work. ‘Ihis convenient arrangement preserves the ad- justment of the length of stroke, and at the same time allows any length of movement of the table by hand. Ly simply dropping this device on the Iever, the ma- chine will continue reversing as before. The cross feed by which the emery wheel is brought against the work to be ground, is operated by a gradu- ated hand wheel. ‘These graduations read to .000§ of an inch, By use of the stop top screw on rim of this wheel, the wheel slide can be moved as little as .00005, and .ooor of an inch can be ground from the diameter of the work. ‘This screw forms a convenient stop to prevent accidental jamming of the wheel into the work and damage to one or the other, or both, As previously stated, the wheel bed and wheel platen swivel, and the wheel is fed smoothly at what- ever position or angle the wheel slide, platen or stand may be set. These universal features of the cross feed are in- dispensable in grinding large tapers, either external or internal. 59 Fig. 24. BROWN & SHARPE MFG. CO, 54 Head BROWN & SHARPE MFG. CO. The base plate of the head stock, shown in Figs. Block. 25 and 26, is bolted to the swivel table of the machine, as already explained. ‘The head stock is clamped to the base plate with two bolts on oppasite sides, and the heads of these bolts are free to slide in a circular T slot. ‘lhe head stock swivels upon a central pin, and its whole circumference at the lower end is graduated to degrees, so that it can be set at any desired angle. The upright supporting the forward bearing on the spindle is heavy to absorb all vibration, while the bear- ing itself is long and of unusual diameter. ‘The spindle is made of crucible steel, and both the front and ’ rear bearings are hardened, ground and lapped. These bearings are unusually far apart to secure rigidity and perfect alignment of the spindle while it is being used for hole and face grinding. ‘he pulley which drives the spindle for this work is placed between the uprights, ‘he boxes are bronze, ground and fitted to the bearings. ‘Their material makes it possible to run the spindle when they are tightly clamped upon it, and this clamping is necessary to obtain perfect face and hole grinding. ‘The clamping adjustment is simple and positive. ‘The end thrust of the spindle is taken entirely on the forward bearing, and lost motion is con- veniently taken up by check nuts with fine threads. The thread is not cut up to the shoulder, but a bearing is left on the forward end of the spindle so that chucks or fixtures can be made to run true within a very small limit. ‘bis: bearing and the taper hole in the spindle are ground when the spindle is in place. The spindle projects through the rear dust cap to allow a bolt to be passed through its entire length to secure work to the face plate when it is desired to true the periphery of a piece in which a hole is to be ground, A stop is provided for holding the pulley between the uprights and preventing the spindle from turning when work is to be revolved upon centres. In addition to this driving pulley the head stock is provided with smail and large dead centre pulleys BROWN & SHARPE MFG. CO. 55 ee wT) MUR rier [= ss] Figs 26. Eos wweesg 40 FO CT] PO SAA on a Fig. 26,. 56 Foot Stock, Wheel Spindie and Boxes. BROWN & SHARPE MFG, CO. Work may thus be ground not only upon the live spindle but also upon two dead centres or upon one dead and one Jive centre. ‘Ihe advantage of grinding work upon two dead centres is that any possible imperfection in the spindle bearings does not effect the accuracy of the grinding. The foot stock is secured to the swivel table by a clamp lever and eccentric. The spindle is quickly operated by a lever, and the work is held between the centres by a stiff spring. By this arrangement the spindle adjusts itself to the varying length of the work caused by expansion, and the pressure between the centres remains substantially constant. The spindle may also be clamped when grinding large work or work not injuriously affected by the change of temperature caused by grinding. “There is an oil reservoir for oiling the centres. Both head and foot stock spindles are hollow, hav- ing a 34-inch hole through them for the purpose of re- moving the centres. Sections of the wheel stand and spindle are shown in Figs. 27 and 28. ‘The spindle is steel hardened, ground and lapped. The end play is taken up with the nut, A, B being its check screw. ‘his provides for the very delicate ad- justment necessary in accurate grinding, The boxes are bronze, 4% inches long and 1% inches in diameter. Turning the nuts, C and D, towards the back of the machine takes up the wear, ‘The boxes are tapering outside, and are fitted to sleeves, which, at the centre of their length, have ball joints formed upon them, and rest in seats provided in the uprights, to which they are clamped by the caps # /, which are hinged and held down by bolts and nats 4, Fig. 28. By this arrange- ment, self-aligning boxes are secured, and the entire arrangement may be removed or replaced, or turned end for end, with the greatest facility, and without disturbing the adjustment of the boxes, Oil is supplied to the spindle through the feit, 4, which is supported by a spring. ; CP 5 A ALL ik RR EO 5 PPT ee RIEL NR UNE EW TO eT are ina ~ wn BROWN & SHARPE MFG, CO, BROWN & SHAKPE MFG. CO. - Fig. 23, | | | BROWN & SHARPE MFG. CO. 60 Driving Pulley. Overhead Works. Brake. BROWN & SHARPE MFG. CO. The effort has been made throughout to prevent vibration in the wheel. It is anchored to 500 pounds of iron in the wheel stand, platen, slide and bed, and these rest upon the base, which weighs 900 pounds. The driving pulley and the flange are made in one piece. The pulley is 434 inches in diameter, while the one on the No. 2 Universal Machine is 234 inches in diameter. It is fitted to the taper arbor at /, and is held in place by the nut, /. A smaller emery wheel is used on the end of the spindle for backing off cutters, reamers, etc. For internal grinding, an extra spindle and boxes are furnished to take the place of the emery wheel spindle. bis spindle has two pulleys, Z and w, Figs. 23 and 24, and serves as a counter-shaft for driving the internal wheel spindle. The overhead works consist of three shafts with two drums, with tight and loose pulleys to inches diameter for 3-inch belt, ‘he shafts should run in the direction indicated by the arrows, Figs. 29, 30 and 31, and are arranged for six speeds between 1,300 and 2,000 forthe emery wheel, and for twelve speeds between 36 and Soo for the work. ‘The drum shaft is driven by a 1}4- inch belt, the emery wheel by a 15@-inch belt, the feéd cone by a 13-inch belt, the head stock spindle and dead centre pulley by a 14-inch belt, and the pump bya 1}4- inch belt, The motion of the emery wheel is controlled by the main belt shipper, while that of the work is con- trolled, independently of the wheel, by the shipper, 4, Vig. 29. By this means work can be changed on the centre, or chuck, without stopping the wheel. This saves time and allows the wheel to be in full motion when commencing to grind. That no time may be lost in waiting for the work to stop revolving after it is ready to be removed from the machine, a friction brake is connected with the rod, O, Fig. 31, When the clutch is released the brake is applied, and the work may be stopped almost instantly. i PES SGRT STE ASS ce aI Ra DR Se 62 Location of the Machine, Drawing. Speed, Hangers. ‘Wet Grinding. Capacity of the Machine. BROWN & SHARPE MFG. CO. The relation of the counter shaft to the machine should be such that a plumb line, dropped from the front edge of the work drum will intersect the front face of the head stock pulley, as shown in Fig. 30. The distance from the centre of the machine to the end of the work drum is 2 inches, as shown by Fig. 29. A copy of a large scale drawing, with figures giving the correct location of the most important parts of the counter shaft, is sent with every machine. The speed of the front counter shaft should be 325 revolutions per minute. The hangers are provided with self-adjusting and self-oiling boxes. Provision is made for wet grinding by a centrifugal pump with connections for distributing the water either upon the wheel or work. The machine will receive work between centres 12 inches diameter and jo inches Jong, while the table may be fed several inches beyond that length. ‘he swivel table may be set either side of its central position to grind tapers from zero to 2 inches per foot, or from zero to § degrees in angular measure. For grinding work on the face plate, or chuck, as shown in Figs. 46 and 47, the head stock may be set to any angle within the whole circle. ‘lhe wheel slide has a move- ment of 6 inches, and may be fed at any angle from zero to go degrees on either side of a line at right angles with the sliding table. The wheel stand will take a wheel 12 inches diameter and % inch thick, with 5-inch hole. The internal grinding fixture usually sent with the machine will grind holes 534 inches long, 1 inch and upwards in diameter. Wheels up to 2 inches in diameter are used with this fixture, The weight of the machine boxed ready for ship- ment is 4,000 pounds, ‘The floor space, measured over extreme projections and points of travel of the various parts, is 47 x 122 inches. 64 BROWN & SHARPE MFG, CO. Machine to This machine is also made to take 4o inches be- ries tween centres. Weight, 4.200 pounds; floor space, Oentres. 47 X 152 inches. Attach- ‘The machine is provided with a drawing showing ments and Location of overhead works, a copy of this treatise, an ries, internal grinding fixture, three-jawed chuck, special chuck for thin cutters, special spindle pulleys with bearings for internal grinding, face plate, wheel tru- ing stand, centre rest, back rest, tooth rest, large and small dead centre pulleys, centres, arbors, pump, wrenches, dogs, and complete overhead works. 165 BROWN & SHARPE MFG. CO, 66 BROWN & SHARPE MFG. CO. FIG, 32. BROWN & SHARPE MFG. CO. No. 3 UNIVERSAL GRINDING MACHINE, A general view of the machine is given in Fig. 32, The bed is supported by two hollow pedestals, which form closets for the reception of various articles that are frequently used about the machine. The head and foot stocks are mounted upon a swivel table, which rests directly upon the bed and turns on a central stud, ‘This allows the line of centres to be set at any angie with the centre line of the machine, for the purpose of grinding tapers, without throwing the head and foot stock spindles out of line. When set to any desired position, the table may. be clamped at each end to the bed. 67 General Sonstone: Table. For the purpose of setting the table accurately to Adjusting grind any desired taper, it is provided with an adjust- ing pinion and a scale graduated to show the taper both ‘in degrees and inches per foot. The scale marked “taper in inches per foot,” gives the whole taper of the work, and the scale marked “degrees,” gives the taper from the centre line of the work, or one-half of the whole taper, which is the angle the swivel table is set out of line. By this arrangement very accurate settings can easily be obtained. The head and foot stocks are gibbed to the table, and may be set at any point upon it, which is a con: venience in using the machine for a variety of purposes. The upper surface of the table is inclined back- . ward, Fig. 33, for the purpose of conducting the water used in grinding toward a channel on the back side of the bed, from which it passes through a pipe at one end. Screw Scale for Tapers, 68 Wheel Bed, Wheel Stand. Wheel Guard. Feed. Reversing. BROWN & SHARPE MEG. CO. The wheel bed may be turned in a horizontal plane and a semi-circumference at its lower edge is graduated to degrees so that it may be set at any desired angle relative to the bed of the machine. When properly set it may be clamped by bolts on opposite sides of the carriage. The wheel slide moves on wide, flat bearings, and is held in place by a 45 degree angular gib. The slides are completely protected from dust. The wheel platen rests on a flat, circular bearing, the mean diameter of which is greater than the dis- tance between the bearings of the wheel spindle. A steady support for the wheel stand is thus provided and rocking is prevented. The wheel platen is held in place by a bolt on each side. The object in thus arranging the wheel platen so that it may swivel is to enable the operator to bring the face of the wheel parallel with the line of travel of the wheel slide, as shown in Fig. 46. _In internal grinding this wheel platen is turned around and the wheel stand proper is used as a speed counter, while the internal grinding fixture is placed on the opposite end of the wheel platen, which in this position projects over the wheel slide and brings the wheel spindle into the proper position for grinding holes. The wheel stand is secured in any position on the wheel platen by two T bolts. The wheel guard is heavy, and is bolted to the wheel stand, It serves to protect the operator from sparks, dust and water, and is a safeguard in case of ac- cidental breakage of the wheel. The carriage which supports the wheel bed and ad- joining parts is fed longitudinally, either automatically or by hand. The feed is engaged by turning a knob in the centre of the front of the machine. The motion of the wheel carriage is automatically reversed by a lever which is actuated by the sliding collars on the rod at the back of the bed, and the 69 BROWN & SHARPE MFG. CO, 7O Cross Feed. BROWN & SHARPE MFG, CO. carriage is reversed without shock or jar. The collars can be set at any position the same as the dogs on a planer. The machine may also be reversed by using the lever at the front of the machine. The wheel slide is moved and the emery wheel brought against the work to be ground, by a hand wheel at the right of the emery wheel. Twenty revolutions of this wheel advance the emery wheel 1 inch. Below this hand wheel there is a second wheel by which the wheel slide may be quickly moved, ‘Ihe connection for the quick movement is readily made by turning the milled knob. As previously stated, the wheel bed swivels and the wheel may be fed smoothly at whatever position or angle the wheel slide may be set. ‘The head stock shown in Fig. 34 is made to swivel about a central pin, and its whole circumference at the lower edge is graduated to degrees, so that it can be set _ at any.desired angle. The uprights supporting the spindle are heavy, to absorb all vibration, while the bearings are long and of unusual diameter. The pulley which drives the spindle is placed between the uprights. The boxes are bronze, ground and fitted to the bearings. ‘heir material makes it possible to run the spindle when they are tightly clamped upon it, and this clamping is necessary to obtain perfect face and hole grinding. The clamping adjustment is simple and positive. The end thrust of the spindle is taken entirely on the forward end of the front bearing, and is conveniently adjusted by the thrust and check nuts. The spindle has a portion of its forward end ground perfectly true with its bearings, which insures the accurate running of the chuck and fixtures. This bearing and the taper hole in the spindle are ground when the spindle is in place. The spindle projects through the rear dust cap to allow a bolt to be passed through its entire leng*h, to secure work to the face plate when it is desired to true the periphery of a piece in which a hole is to be ground. BROWN & SHARPE MFG, CO, qt i W Fig. 34, 72 Foot Stock. Wheel Spindle and Boxes. BROWN & SHARPE MFG. CO. A stop is provided for holding the pulley between the uprights and preventing the spindle from turning when work is revolved upon centres. The head stock is provided with a small and large dead centre pulley. ‘The small dead centre pulley runs upona stem fitting in the taper hole of the spindle, and the thread on the end of this stem and dead centre pulley is the same as thread on end of spindle and dead centre pulley of No. 2 Improved. Work may be ground upon two dead centres and upon one dead and one live centre, as well as upon the live centre alone. The ad- vantage of grinding work upon two dead centres is that any possible imperfection in the spindle bearings does not affect the accuracy of grinding. The foot stock spindle is large and is operated by a hand wheel and screw, and the work is held between the centres by a stiff spring, By this arrangement the spindle adjusts itself to the varying length of the work caused by expansion, and the pressure between the centres remains substantially constant. By the use of the hand wheel and screw the tension of the spring may be varied, and by tightening the set screw the spindle can be made fast, There is an oil reservoir for oiling the centres, and when the spindle is drawn back the centre is thrown out. A section of the wheel spindle and boxes is shown in Fig. 35. ‘The spindle is hardened, ground and lapped. The end play is taken up with the nut, 4, B being its check screw. This provides for the very delicate adjustment, necessary in accurate grinding. ‘he boxes are 4% inches long and 14% inches in diameter. They are self-aligning and made of bronze. ‘They are adjusted by the nuts, Cand D, and turning both nuts towards the back of the machine takes up the wear. The spindle and boxes can be removed from the wheel stand without disturbing the adjustment of the boxes, and the spindle with the boxes may be turned end for end by turning the cap nuts and raising the caps. 73 BROWN & SHARPE MFG. CO. "96°81 ZZ i iN ZI LL | \y 74 Driving Pulley. Wet Grinding. Overhead Works, BROWN & SHARPE MFG, CO. Oil is supplied to the spindle through the felt, H, which is supported by a spring. The driving pulley and the flange are made in one piece, and the pulley is 4% inches in diameter. It is fitted to the taper arbor at /, and is held in place by the nut, 7. A smaller emery wheel is used on the end of the spindle for backing off large cutters, reamers, etc., and a large wheel may here be used for grinding up to shoulders, collars, etc., as shown in Fig, 36. For internal grinding, an extra spindle and boxes are furnished, This spindle has two pulleys, Z and m, Figs. 23 and 24, and serves as a counter-shaft for driving the internal wheel spindle. Provision is made for wet grinding by a centrifugal pump with connections for distributing the water either upon the wheel or upon the work, The overhead works consist of a compound counter- shaft, Figs. 37, 38 and 39, with a back shaft, forward shaft, and drum shaft, in combination with the hangers, pulleys and shippers substantially as shown. The 4%- inch main belt runs on ¢2-inch tight and loose pulleys on the back shaft, and the shaft should revolve in the direction indicated by the arrow. All the belts con- necting the shafts and machine should usually be open. The forward shaft is driven from the back shaft by a 2-inch belt on cone pulleys, with five changes of speed, and the drum shaft is driven from the back shaft by a 234-inch belt on cone pulleys, with two changes of speed. The feed work receives motion from a four- step cone on the front shaft through a 1}4-inch belt, ‘The emery wheel is connected with the drum by a 134- inch belt, A 2-inch belt from the drum on the front shaft drives the dead centre pulley. In grinding small work the small dead centre pulley is used, It is driven by a 14-inch belt. For other kinds of york the pulleyon the head stock spindle is driven from the same drumby a 2%-inchbelt. For convenience in changing these belts, the larger one should have its ends connected with belt hooks so it can be unhooked when put on the pulley. BROWN & SHARPE MFG. CO. 15 76 Brake. Location of Counter Shaft Drawing. Speed. Hangers. Capacity of the Machine. BROWN & SHARPE MFG. CO. The motion of the emery wheel is controlled by the main belt shipper, while that of the work is con- trolled independently of the wheel by the shipper con- nected with the front shaft, By this arrangement the work can be changed on the centre, or chuck, without stopping the wheel. Time is thus saved as the wheel is always in motion when brought against the work. That no time may be lost in waiting for the work to stop revolving after it is ready to be removed from the machine, a friction brake is connected with the shipper on the front shaft. By this means the drum, and consequently the work, may be stopped almost instantly. The relation of the counter shaft to the machine should be such that a plumb line dropped from the centre of the drum, Fig. 38, will intersect the line of centres of the machine. ‘The front shaft is placed by the cone from which the feed cone is driven, and the positions of the other shafts are determined by the cone pulleys. A copy of a large scale drawing, with figures giving the correct location of the most important parts of the counter shaft, is sent with each machine. The speed of the back counter shafts should be about 250 revolutions per minute. The hangers are provided with self-adjusting and self-oiling boxes. The machine will receive work between centres 20 inches diameter and 6 feet long, and the swivel table will swing to either side of its central position to grind tapers from zero to 2 inches per foot, or from zero to 5 degrees in angular measurement. The head stock can be set to any angle within.the whole circle, and the wheel slide has a movement of 12 inches, and can be fed at any angle from zero to go degrees on either side of a line at right angles with the ways of the machine. The wheel stand will take a wheel 12 inches diameter and '-inch thick, with a 5-inch hole in centre, S oO 3 5 a a ay 4 4 a n 3 ta 8 % a ; = "a0 . a THe i OS = | eri = & & = = aS ae o) InN Z A [oy iS CS Fig. 39, 80 Attach- BROWN & SHARPE MFG. CO. The internal grinding fixture usually sent with the machine will grind holes 54 inches long, 2 inches and upwardsindiameter, Wheels upto 3 inches in diameter are used with this fixture. When a large wheel is used on the end of the spindle, a piston rod, for example, may be ground up to a piston 20 inches in diameter. The weight of the machine boxed ready for ship- ment is about 8,400 pounds. The floor space, measured over extreme projec- tions and points of travel of the various parts, is 63, inches by 12 feet. Each machine is furnished with a drawing showing mentsandigcation of overhead works, a copy of this treatise, an Accesso- ries. internal grinding fixture, a special speed pulley with spindle and bearings for internal grinding, a three- jawed chuck and centre rest, two back rests, wheel arbor for small wheels, large and small dead centre pulley, centres, dogs, pump, wrenches and complete overhead works, BROWN & SHARPE MFG. CO. INTERNAL GRINDING FIXTURE. The Internal Grinding Fixture, recently patented, is a decided improvement upon earlier fixtures. For- merly it was customary to employ a solid spindle or shaft, with a driving pulley at one end and a small wheel at the other end. ‘lo grind holes of any con- siderable depth the end of the spindle necessarily pro- jected acorresponding distance beyond the bearing, and any motion or play in the bearing was multiplied at the end of the spindle so that even a slight motion or play in the bearing caused a considerable movement at the end of the spindle and necessarily produced imperfect work. In order to give it sufficient rigidity the spindle was made of a considerable diameter, but this large diameter rendered impossible the attainment of the high speed requisite for thoroughly efficient work. Also, when pressure-was brought upon the end of the spindle by the action of the wheel upon the work, this pressure tended to force the spindle against its bearing with considerable power, owing to the leverage, due to the distance between the grinding wheel and the bearing, and this necessarily produced a great amount of fric- tion between the spindle and the bearing and tended to prevent the attainment of high speeds. The present fixture overcomes these difficulties, and is thoroughly efficient. It consists, primarily, of a grinding spindle of comparatively small size, mounted in a bearing of telescopic tubes of sufficiently large diameter, to give the required rigidity. These tubes are adjustable, longitudinally relatively to each other, and furnish a support or bearing for the spindle in close 8r 82 BROWN & SHARPE MFG, CO, Ria aE AZ am jl e [pte BROWN & SHARPE MFG. CO. proximity to the grinding wheel. The small-diameter of the spindle enables it to be revolved at the neces- sary high speeds. Figs. 40, 41 and 42 show the construction. A, is the stand; JB, the wheel spindle bearing ; C, the pulley spindle; DD, the pulley spindle bearings. The bronze box, &, is tapered on the outside to fit in the tapered end of the external tube, /, and this tube is made to screw on to the internal tube, G. It follows, that when the external is turned upon the internal tube, the box, &, will be moved toward or from the internal tube, de- creasing or increasing the end play of the wheel spindle collar, 2. ; When the external tube has been screwed on to the internal tube far enough to take out all end play of the collar, 7, still further movement will force the box, &, into the taper end of the external tube and close the box to compensate for wear. After the box has been forced far enough into the taper, the external tube is unscrewed sufficiently to relieve the pressure on the collar, 7, and make a running fit. In adjusting as above the screw, 7, should be loosened and the spanner wrench used in the notches, J /. The projection of the wheel from the stand has a limited adjustment, which is made by loosening the screws, Zand X. The wheel spindle, with its connect- ing tubes, can be removed from the stand without dis- turbing the pulley and Spindle, as connection is made by the spindles, Z Z, and pins, m m. Provision is made for excluding dust from the bearings. Four sizes of the fixtures may be used on the No. t Universal Grinding Machine, and five sizes may be used on the No. 2 Universal Grinding Machine, No. 2 Universal Grinding Machine Improved, and No. 3 Uni- versal Grinding Machine. In ordering these fixtures it should be stated whether or not they are to be used on the No. 1 Universal 84 BROWN & SHARPE MFG. CO, Grinding Machine, as the fixtures sent for this machine have lower standards than those used on the other machines. No. 1 will grind holes 14!" long, &" to 4"! diameter. wg Hw gy we re Kn “ % 3G “ “gyn 4 EYE or “ ce ay Se ae ow gugik a 1! and upwards ** og ee gy gh “oc Wheels up to 2 inches diameter may be used on the No. 4 Fixture. Wheels as large as 3 inches in diameter may be used on the No. 5 Fixture. Diameter of hole in wheels used on No. 1 Fixture, 3," “ oe a re yn “ fee a OR ag MS yl “ oe woe ga 5qu “ rr rT) wow Yay Speed of No, 1 Fixture, 16,800 revolutions per minute. wow eg 13,400 “ ou BEE BES ay 12,200 a SP a ae 11,200 “ Hoe gw 8,050 “ woe Fixture No. 3 is usually sent with the No, 1 Universal Grinding Machine. Fixture No. 4 is usually sent with the No. 2 Universal Grinding Machine. Fixture No. 4 is usually sent with the No. 2 Universal Grinding Machine, Improved. Fixture No. 5 is usually sent with the No. 3 Universal Grinding Machine, Improved, If any other size is preferred it will be for- warded at the expense of the customer, the fixture sent with the machine being returned without expense to us, .BROWN & SHARPE MFG. CO, MATERIAL, WORKMANSHIP, ETC. Throughout the construction of the machines we Material aim to employ first-class material and workmanship, w, and obtain the highest degree of durability as well as accuracy. All plane surfaces requiring fitting are scraped to surface plates, while all round surfaces, such as shaft bearings, etc., are fitted by grinding, All screws, bolts and nuts requiring frequent adjustment, are hardened. Special attention has been given to the protection of all wearing surfaces from the emery dust, which una- voidably accumulates about the machine. This dust would, of course, ruin a machine in a very short time if it were admitted to the bearings. The feed gearing is completely enclosed. ‘The dust caps, which protect the spindle bearings of the head and foot stocks and wheel stand have been referred to, All oil holes are provided with plugs or screws. and ‘orkman- ship, 86 BROWN & SHARPE MFG. CO. CARE AND USE OF THE MACHINES. SELECTION OF WHEELS—EXAMPLES OF GRINDINGS. Oil and Oiling. Cleaning. As the durability of a machine depends very largely upon the care of the operator, however well a machine may be constructed, if it is not properly cared for it will soon become unreliable. The wearing surfaces should be especially guarded and kept well oiled. In all cases we recommend the use of a good quality of oil in pre- ference to one of low grade. Sperm oil should be used on the Internal Grinding Fixtures. Those holes which are closed with screws have the words “oil hole” stamped around them, and all oil holes should be well guarded. Among the least prominent oiling places in the No. 2 Universal Grinding Machine, may be mentioned the bearing of the cross feed worm which has an oil hole in the centre, on the upper end, and may be oiled after running the wheel slide back out of the way, ‘The oil hole to the bearing of the feed cone, /, in this machine, Fig. 14, is covered by a sleeve encircling the bracket. ‘This sleeve, when turned a quarter of a turn, will expose the hole. The operator should make himself familiar with all oiling places, so none will be overlooked, The counter-shaft hangers should be cleaned out about once a year and re-filled with clean oil. If the oil wicks are found to be badly worn where they come in contact with the shaft journals, they should be replaced by new ones of sufficient length to have the ends well immersed in the oil. The machines should be kept as clean as possible, and in no case should the bearings be allowed to “gum up.” When bearings are opened and exposed for any purpose whatever, they should be carefully wiped off, before they are closed again, to free them from any grit that may have found its way upon the surfaces. BROWN & SHARPE MFG. CO, The spindle boxes should be perfectly clean when put together. Before tightening the cap the oil space G, Figs, 9, 18, 27 and 35, should be filled with good oil, never lard oil, and the wheel turned slowly while first one cap and then the other is screwed until quite tight. The felt by which oil is supplied to the spindle should be kept clean where it rubs on the spindle. A loose fit between the wheel spindle and its boxes will produce imperfect work, and when very fine work is required the bearings should run nearly, if not quite metal to metal. This necessarily will cause the boxes to heat, but in this case the heat is not injurious, for, as the bearings are hard and the boxes bronze, the belt will slip, unless it is exceedingly tight, before abrasion can occur. All end motion should be taken out of the wheel spindle before the wheel is used on the work. The pump is a simple fan revolving in a loose case and the shaft should be kept packed air tight and the driving belt should be open. A satisfactory Emery Wheel is an important factor in the production of good work. Too much, however, must not be expected of one wheel. A variety of shapes, sizes and grades of wheels are necessary to bring out all the possibilities of the Grinding Machine, the same as a variety of shapes and sizes of tools are necessary to obtain the best results from the Lathe or Milling Machine. Our aim in grinding is usually to obtain an accurate or true surface, but as a true surface is almost always a good surface it should be remembered that generally the same methods are employed, whether an exact size ora fine finish is the object desired. Oursuggestions are not offered as positive rules but as the embodiment of our experience and as represent- ing the methods which our shop practice has indicated are desirable. In selecting and using a wheel, we are governed by the character of the metal to be operated upon, the 87 Adjusting Spindle Boxes. End Motion of* Spindle. Pump, Emery Wheels, 88 Coarseness or Fineness of Wheels, Softness or Hardness of ‘Wheels, BROWN & SHARPE MFG. CO. shape and size of the work and the degree of accuracy desired. We have to consider the size of the particles of emery in the wheel, the hardness of the wheel and its width, We also have to determine the speed at which it is to be revolved, the speed at which the work is to travel or be revolved, and whether or not water is to be used, For the sake of clearness we refer separately to the various characteristics of wheels, but it should be borne in mind that a wheel should not be selected for a single characteristic but that each of the essential elements is importantly affected by the others, and that all should be considered in choosing or using a wheel for any desired work, Wheels are numbered from coarse to fine; that is, a wheel made of No. 60 emery is coarser than one made of No, 100. Within certain limits, and other things being equal, a coarse wheel is less liable to change the temperature of the work and less liable to glaze than a fine wheel. Asa rule, the harder the stock the coarser the wheel required to produce a given finish. For example, coarser wheels are required to produce a given surface upon hardened steel than upon soft steel, while finer wheels are required to produce this surface upon brass or copper than upon either hardened or soft steel. Wheels are graded from soft to hard and the grade is denoted by the letters of the alphabet, A denoting the softest grade. A wheel is soft or hard chiefly on account of the amount and character of the material combined in its manufacture with emery or corundum, But other characteristics being equal, a wheel that is composed of fine emery is more compact and harder than one made of coarser emery. For instance, a wheel of No. roo emery, grade B, will be harder than one of No. 60 emery, same grade. The softness of a wheel is generally its most im- portant characteristic. A soft wheel is less apt to cause a change of temperature in the work, or to become BROWN & SHARPE MFG. CO. glazed than a harder one. It is best for grinding hard- ened steel, cast iron, brass, copper and rubber, while a harder or more compact wheel is better for. grinding soft steel and wrought iron. As a rule, other things being equal, the harder the stock the softer the wheel required to produce a given finish, Generally speaking, a wheel should be softer as the surface in contact with the work is increased. For example, a wheel 54; inch face should be harder than one finch face. If a wheel is hard and heats or chat- ters, it can often be made somewhat more effective by turning off a part of its cutting surface; but it should be clearly understood that while this will sometimes prevent a hard wheel from heating or chattering the work, such a wheel will not prove as economical as one of the full width and proper grade, for it should be borne in mind that the grade should always bear the proper relation to the width. The width should be in proportion to the amount of material to be removed with each revolution, and as a wheel cuts in proportion to the number of particles in contact with the work, less stock will ordinarily be removed by a narrow wheel than by one that is of full width, The feed will also have to be finer if a narrow wheel is used. ‘ The quality of the work as a rule is improved by using a wheel of full width if the wheel is soft in pro- portion. Judgment should be exercised in deciding upon the width of wheel to be used, as sometimes the work is of such size and shape as to make it necessary to use a wheel with a narrow face. Where this is the case the wheel should, where strength will admit, be only that width throughout, and care should be taken 89 Width of Face of Wheel, that the grade is kept in the proper relation to the width. ° A wheel is most efficient in grinding just at the point before it ceases to crumble. The faster it is run up to this point the more stock will be removed and the more economically the work will be produced. Occasion- ally, however, it is necessary to run a wheel rather Speed of Wheel. -9o Speed of Work, Accurate Grinding. BROWN & SHARPE MFG. CO. slowly, as the more slowly it runs the coarser it cuts and the less likely it is to change the temperature of the work. As a general rule, on any given stock, the softer the wheel the faster it should be run, Should a wheel heat or glaze it can often be made somewhat more effective by being run more slowly. On the other hand if it be too soft, it can often be made to somewhat better hold its size and grind straight by being run more rapidly. The surface speed of the work should be propor- tionate to the speed of the wheel, that is, other things being equal, if the speed of the wheel is reduced the speed of the work should be reduced also, The desire is to have the work revolve at such a speed as to allow time for the wheel to cut away the high points on the work. Ifthe work is run so fast that there is no time given for the wheel to cut, but the work is simply crowded against the wheel, the tendency is for the wheel to follow the inequalities in the form of the work and straight or round surfaces are not obtained, When the wheel is not free cutting and the pressure of the wheel against the work is sufficient to cause the work itself to spring or to cause a slight movement of the oil upon the centres the accuracy of the result is impaired. The coarser or softer and more free cutting the wheel the greater can be the speed of the wheel, and consequently of the work, It is, however, not necessary to graduate the speed of the work as closely as the speed of the wheel. The character of the wheel being in- fluenced so readily by a change of speed it is sometimes essential and often very convenient on Universal Grind- ing Machines to be able to slightly increase or decrease the speed of the wheel. The desire in accurate grinding is to have a free cutting wheel and to obtain the proper speeds so that the stock may be removed with the least possible amount of pressure, thus preventing a change of temperature in the work and allowing the high parts to be most speedily reduced. BROWN & SHARPE MFG. CO, Thus far we have had in mind the selection and use of wheels for the comparatively small or medium sized work ordinarily ground on our machines. ‘The require- ments in grinding extremely large or long pieces are somewhat different. For example, in grinding a piece of steel three inches long, one inch diameter, on a Universal Grinding Machine we have indicated that the most absolutely accurate work would be accomplished by selecting a wheel only just hard enough to retain its size while passing six or eight times over the surface of the piece, and we have suggested that such a wheel should be run at a high rate of speed. We have con- sidered rapidity of production as more important than economy of emery. If, however, we should attempt to use such a wheel to grind a piece of steel one inch diameter and three feet long, it is clear that before the wheel had passed over two of the three feet it would have ceased to cut. : The problem now is to maintain the diameter of the wheel so as to take a uniform cut over a large area. Each particle of emery must be used as long as possible before being thrown away. A wheel full width and full diameter should be used, and the face should be true so that as many particles as possible may be brought in contact with the work, and each particle be dulled as little as possible while the wheel is passing over the work, ‘The particles may be used a longer time and are not so rapidly thrown away in a hard as in a soft wheel. Accordingly one expedient in grinding large areas is to increase the grade of the wheel as the area increases, the speed of the wheel being reduced as the grade is increased. The loss of fine particles will not decrease the diameter of the wheel as rapidly as the loss of coarser or larger particles. . Thus another expedient is to use a finer wheel. A fine wheel can be relatively softer than a coarser wheel, and so with a fine one there need be less pressure between the wheel and the work and there is more certainty of obtaining an accurate surface. gr Require- ments in Grinding Large or Long Pieces. g2 ‘Water. BROWN & SHARPE MFG. CO. If a wheel is run rapidly the particles of emery soon become dull and have to be thrown away, To retard this loss it is well to run the wheel more slowly as the length or area of the work increases. If the speed of the wheel is reduced the speed of the work should be reduced accordingly. As the length or area of the work increases the feed should be coarser, so that the wheel may travel the entire length or area of the piece while its diameter is practi- cally unchanged. Water should be used on such classes of work as are injuriously affected by a change in temperature caused by grinding. It should be used upon work revoived upon centres, as in this work a slight change of temper- ature will cause the wheel to cut on one side of.the piece, after it has been ground apparently round. In very accurate grinding water is especially useful, for it should be remembered that the exactness of the work will be affected by a change in temperature which is not perceptible to the touch. In very accurate grinding it is also well to use the .water over and over again, as by so doing there is less Internal Grinding. Summary. difference between the temperature of the water and that of the work than if fresh water is used. For many purposes soda water is the most satisfactory, as it has less tendency to rust the work or the machine. For internal grinding it is especially important that a wheel should be free cutting and the work revolved so slowly as to enable the wheel to readily do its work- ‘The wheels should generally be softer than for external grinding, as a much larger portion of the periphery is in contact with the work. ‘Their small diameters make it impossible for the proper periphery speed to be obtained, and this must be considered in regulating the speed of the work. . To repeat some of the more important suggestions offered above, the numbers given on the labels denote the coarseness, and the letters indicate the grades of the wheels. BROWN & SHARPE MFG. CO. 93 94 BROWN & SHARPE MFG. CO. Fig, 44, BROWN & SHARPE MFG. CO, Soft free cutting wheels such as are made by a number of the companies using the vitrified process are the best for most purposes. - ‘Ihe ideal wheel is the one composed entirely of cutting materials. The width of the wheel should be in proportion to the amount of stock to be removed at each revolution. The wheel should be soft in proportion to the surface in contact with the work, ‘The speed of the wheel should be in proportion to its softness, and the speed of the work should be in proportion to the speed of the wheel. The wheels listed at the end of this book are those which our experience has shown to be suitable for the various purposes specified. Special cases may demand changes in the grade letter, but under ordinary circum- stances the list should be accepted as a guide. The speed, diameter and width of wheels, and the number of the emery cannot be changed without chang- ing the grade and cutting qualities of the wheels. Wheels should always be kept true. They-can be easily kept so by truing them off with a diamond tool, known as the black diamond or carbon point, held by hand or in the fixture sent with several of the machines. A new wheel should be started slowly and trued gradu- ally. Fig. 43 shows the method of truing the face, Fig. 44 the side of a wheel. In mounting emery wheels there should always be elastic washers placed between the wheel and the flanges. Sheet rubber is best for this purpose, but soft leather will answer very well. In some cases manufac- turers of emery wheels attach a thick, soft paper washer to each side of the wheel for this purpose, in which case no further attention is required in this direction. 95 List of Wheels, Truing Wheels, Mounting Wheels. The wheel with its pulley can be removed from the Removing spindle at any time by: unscrewing the nut /, and screwing up the nut X, Figs. 9, 18, 27 and 35. In no case should a hammer be used for removing the wheel. In all kinds of grinding the work should move in a direction opposite to that of the wheel at the cut- ting point, as shown by the arrows in Fig. 21. Wheel from Spindle. Direction in which 96 Lapping. ‘True Centre Holes. True Face Plates, Different Methods of Grinding. Grinding Slight ‘Tapers. Grinding Abrupt Tapers, BROWN & SHARPE MFG. CO, Where a high finish is desired on hardened work, such as jewelers’ rolls, standard gauges, etc., the final finish is usually given by lapping. To obtain good results when the grinding is done on the centres:it must be remembered that true centre holes in the work, as well as true centres, are absolutely necessary. The face plates should be kept true. They can be readily ground in place on the machines. From the description of the machines it may be noticed that work can be ground on the live spindle in the head stock, or that it may be ground on one dead and one live centre, being driven by the pulley between the uprights on the head stock, or upon two dead centres, the work in this case being driven by the large or small dead centre pulley furnished with each machine. Also from their construction it is clear that for plain grinding, the various parts of the universals are set practically the same as corresponding parts of the plain grinding machine. When slight tapers are desired for either external or internal grinding, the swivel table is set to the proper angle. When more abrupt tapers are wanted for work ground on centres or for internal surfaces, the wheel slide is set to the proper angle. By placing the wheel slide and the swivel table at the proper angles, two tapers, for either external or internal work, may be ob- tained without changing the settings of the machine, the one automatically by the longitudinal movement of the table, the other by operating the cross feed by hand. When an abrupt taper is required on work held on the head stock spindle, independent of the foot stock, the taper is obtained more conveniently by swiveling the head stock than by setting the wheel slide. In this case the work is driven by the pulley between the uprights on the head stock. BROWN & SHARPE MFG. CO. 97 This pulley is frequently used for driving large See work ground on centres, when it is desirable to run centres, slowly.. Most work, however, when ground on centres is driven by the large or small dead centre pulley. Most pieces, whose internal surfaces are ground, are driven by the pulley between the uprights on the head stock. The advantage of grinding on two dead centres is Advantage that any possible play in the spindle bearing does not Grinding affect the character of the work, Centres. In grinding straight work both ends should be cal- Grinding ipered. If one end measures a little more than the =e other, the defect may be corrected by swinging the table / atrifle by means of the adjusting screw X, Fig. 13. Sometimes it is more convenient to correct this defect by taking a slightly heavier cut at the large end. By very great care the wear of the wheel can be practically offset by feeding up the wheel, but the best method, in most instances, to straighten work is to take a number of very light cuts. Passing from these general suygestions, the reader Examples will gain a clearer idea of the manipulation, use and Speen arrangement of the machinés by studying the descrip- tions and illustrations of special operations. In Figs. 3, 10, 11, 13, 14, 21, 29, 30, 33, 37 and 38 Plain the machines are shown properly arranged for parallel Sues or plain external grinding. The work, in Figs. 3,2tand y,, of 33, is shown supported by a back rest. It is used Back to absorb vibration caused by the emery wheel in Re slender pieces, and should be so placed that only the high points of the work will touch as the work is re_ volved. When it is thus placed and a light cut is taken by the wheel the back rest assists in the production of round or approximately round work, and the cut of the wheel and the pressure on the rest may be increased as the work approaches to a perfectly cylindrical form. In other words when work is first commenced ona piece the back rest should be considered more as an absor- bent of the vibration than as a support. After the work has become quite round the rest can be used to regulate ° 98 BROWN & SHARPE MFG. CO. the size at different points. This method of using the rest is particularly advantageous in grinding pieces that are apt to be large midway from the ends. Slender work, until it becomes approximately cylindrical, as a rule, requires a very coarse feed when the back rest is used. The back rest is stationary when used for straight grinding on the No, 1 and No. 2 Universal, No. 2 Universal Improved and No. 2 Plain Grinding Machines, On the No. 3 Universal Machine one of the rests is arranged to travel with the wheel and the other is station- ary. In Fig. 45 the use of a back rest is shown in taper grinding on the No. 1 Machine, The rest here is fastened to the table by means of a special block and travels with the work. Figs. 21 and 33 illustrate two kinds of back rests, that in Fig, 33 being usually preferred when grinding slender work or very long pieces. Sometimes the wooden point of the back rest is replaced by soft metal, which conforms, by wear, to the shape of the piece to be ground. The exact way in which a back rest must be used depends upon the various conditions existing in each individual case. Plain Fig. 36 shows an example of plain grinding which Grinding may be done onthe No. 3 Universal Grinding Machine. ane on In this, as in the previous cases, the automatic longitu- bests dinal feed is used; the wheel is brought up against * the work by means of the cross feed, and the work is on centres and driven by the large dead centre pulley. ‘The wheel, however, inthis example is not on the centre of the wheel spindle, but on the end, the object being to grind up to a shoulder, collar or piston as shown. The wheel is driven by the small pulleys on the centre of the spindle the same as in internal grinding, and the length of the stroke is regulated by the collars on the rod at the back of the bed. For very many operations a small wheel is convenient on the end of the spindle, and FIG. 45, BROWN & SHARPE MFG. CO, may be so used on either Universal Machine. A large. wheel is thus used only on the No. 3. The adjustment of the machines for plain internal grinding is shown by Fig. 23. The wheel platen and the wheel stand are turned about the central stud 180 degrees from the position usually occupied in plain ex- ternal grinding and shown in Fig. 21. The internal grinding fixture is bolted to the forward end of the wheel platen, and the spindle of this fixture is driven from a small pulley which is substituted for the emery wheel on the centre of the spindle of the large wheel stand. In internal grinding the belt from the overhead works to pulley # must be crossed and the emery wheel run backwards or opposite to the direction shown in Fig, 36. he work is held in the chuck and run for- ward in the usual way as indicated by the arrow. Here, as in external grinding, the emery wheel is brought against the work by means of the cross feed, while the automatic table feed may be used for feeding longitud- inally and the length of stroke is regulated by the dogs on the front of the table. ‘The piece might be strapped to the face plate instead of held in the chuck as shown. The arrangement of the machines for grinding ex- ternal tapers, not over 134 or 2 inches per foot, isshown by Figs. 22 and 45. It is the same in all respects as for plain grinding except that the swivel table is set at the proper angle. The reading on the scale marked degrees, it should be remembered, is one-half the whole taper. Where the work isto be ground toa fit, it is usually placed in the machine in the manner shown, the smallest end of the taper being toward the foot stock, The wheel and the table are operated, the work is driven, and the length of the stroke regulated the same as in plain grinding. Ior Plain Internal Grinding. Grinding External ‘Tapers. When an abrupt taper similar to that shown in Fig.: 46 is to be ground, the swivel table remains parallel to the ways of the bed as in plain grinding, but the wheel 102 Two Tapers with One Setting. Grinding Spindle and Box, Grinding Internal ‘Tapers. BROWN. & SHARPE MFG. CO. bed is set to the angle which brings the line of motion of the wheel slide when operated by the cross feed, parallel with the taper to be obtained. The wheel platen is set at right angles with the line of movement of the wheel slide, indicated by the arrow, and the face of the wheel is thus brought parallel with the line of the de- sired taper. The work is revolved by the dead centre pulley, as shown in cut, and the wheel is moved over the surface of the work by the cross-feed, The method of grinding two tapers with one setting of the machine when one of the tapers is not more than 10 degrees is shown in Fig, 47. For grinding the slight taper the swivel table is set as in Fig. 22, and for grinding the more abrupt taper tne wheel bed is set as in Fig. 46. But the wheel platen is here set to bring the face of the wheel parallel with the longest surface to be ground. Were the abrupt taper longer than the slight taper it would be well to set the wheel platen as in Fig. 46, so that the face of thewheel would be parallel with the line oftaper. In obtaining the angle at whichthe wheel bed is tobe set when the swivel table has been set over, it should be remembered that the angle must equal the sum of the two tapers, The abrupt taper is ground by feeding the wheel across the work by hand. ‘The slight taper is ground while the table is fed automatically, When, as suggested by the cut, a spindle and box are both to be ground, the box is ground first and the spindle is, fitted to it. For convenience in fitting the work, the ‘box may be placed as shown by the dotted lines and supported so that it will not touch the spindle as the latter revolves. The spindle thus need not be removed from the centres when it is necessary to try it in the box. * In grinding the box the machine is set as shown in Fig. 24. Provision is made for grinding the slight taper by setting the swivel table and for gtinding the abrupt taper by swiveling the wheel bed. As in exter- nal grinding, the bed is set so that the line of motion of BROWN & SHARPE MFG. CO, 104 SSS BROWN & SHARPE MFG, CO, Io5 Fig. 29: BROWN & SHARPE MFG, CO, 106 FIG, 50. e@ s—- 108 BROWN & SHARPE MFG. CO. the wheel slide will be parallel with the line of the taper to be ground. The angle with the ways of the machine in this case, the swivel table having been set over, is equal to the difference in the angles of the tapers. As in external grinding, the abrupt taper is ground by feed- ing the wheel across the work by hand and the slight taper is ground while the table is fed automatically. Fig. 48 illustrates work ground on the No. 3 Uni- versal Machine, " ees Fig. 49 shows a method of squaring the end of Bushings, Steel bushings. The wheel is turned away on the side, leaving a narrow cutting corner, and should be very soft. If the axis of the arbor and the axis of the wheel spindle are exactly parallel the surface will be perfectly flat and at right angles with the axes, A concave or convex surface can be obtained by varying the relation of the axes. Work A great deal of odd work in manufacturing ma- Swung by ° 5 Manton chinery may be done on the machines; for example the Centres. spiral box of the milling machines, Fig. 50, may be swung on centres by hand and the curved surfaces, shown at the right in the cut, may be satisfactorily ground, Grinding The accuracy of all work ground on centres is so Pb iaed dependent upon the centres being true that the opera- realy “tion shown in Fig. 51 is very frequently seen, ‘To grind Centres, or true a centre it is only necessary to set. the head stock to the proper angle, and this can be done on the plain as on the universal grinding machines. Grinding Fig, 52 shows another illustration of the class of om work ground by swiveling the head stock in which may be included grinding the sides of collars, washers, mill- ing cutters, etc. The plate or disk shown is held in the chuck, and the head stock is turned at right angles to the sliding table, The wheel is brought against the work by the cross-feed and the automatic table feed can be used for passing the work in front of the wheel. It is evident that the surfaces ground in this manner may be plain, concave or convex, according to the setting of the head stock. BROWN & SHARPE MFG, CO, 109 TIo Use of Centre Rest. Use of Special Chuck, Grinding Cutters and Reamers, BROWN & SHARPE MFG. CO. Two surfaces may be ground on pieces held in the head stock with only one setting of the machine. For example, if the portion of the work ground in Fig. 46 were detached from the shaft or arbor and it were de- sired to grind the flat and bevel surfaces, the head stock would be turned at right angles to the table as in Fig. 52, and the wheel bed would be set to such an angle that the line of motion would be parallel with the taper. The general position of the wheel and wheel platen in this case is suggested by Fig, 24. Fig. 53 shows an operation similar to Tig. 52, but the piece is here ground by a small wheel on the end of the spindle. Fig. 54 illustrates the use of the centre rest in con- nection with work held in the chuck on the head stock, the work being driven as in Fig. 23 and theswivel table set to produce the desired taper. ‘Ihe cut also illus- trates the use of an indicator to determine that the work runs absolutely true. Thin washers and cutters are conveniently mounted on a special chuck furnished with the machine. This chuck, as indicated by Tig. 55, holds the cutters by the hole in the centre and should be used in all disk grind- ing where both sides of the pieces must be parallel. Vor most disk grinding it is also more convenient than a common chuck and more accurate results are generally attained by its use. hin saws, Tig. 56, are held this way and are ground concave or thinner at the centre than at the teeth, to give the proper clearance. The machines are used for grinding the holes in milling, form and gear cutters, Vigs. 57, 58 and 59, as well as for grinding their sides or ends ‘They also are suitable for grinding the teeth or cutting edges of a large variety of cutters and reamers, and for use on this work are provided with a tooth rest which may be bolted to the wheel platen at one of its 7’slots. The ordinary place for the tooth rest, when in use, is directly in front of the wheel as in Fig. 60, where the face of a side milling cutter, Fig. 61, is being ground, OWN & SHARPE MFG, vO, BROWN & SHARPE MFG. CO, 114 BROWN & SHARPE MFG, CO. FIG. 56. FIG, 57. Fig. 60. BROWN & SHARPE MFG. CO. Fig..62. 116 BROWN & SHARPE MFG, CO. the cutter being held ona mandrel. To get the necess- ary amount of clearance or backing off to the tooth the end of the rest which supports the tooth must be set a little lower than the centre of the wheel, so that the ground surface will have the proper clearance angle. For this kind of work the wheel must, of course, be small enough to clear the tooth next above the one be- ing ground. Fig. 62 is a top view, showing areamer on centres. The machine is very quickly and conveniently operated by grasping with one hand the shank of the reamer, or the mandrel as the case may be, and holding the tooth firmly upon the tooth rest, while the other hand is engaged in feeding the reamer, or cutter, across the face of the wheel with the crank wrench, or hand wheel. When a tooth has been run by the wheel and off the tooth-rest the reamer, or cutter, may be turned to bring the next tooth upon the rest, and the table moved in the opposite direction whileit is being ground, ‘Thus a tooth can be ground at every stroke of the table when the grinding is done simply for the purpose of sharpening; but when it is necessary to grind a cutter to a certain diameter, it must, of coarse, be ground repeatedly until the required size is obtained. As the tooth slides over the tooth rest, in feeding it by the wheel, it is obvious that the clearance will always be the same whether the teeth are straight or spiral, since the relation of the tooth to the wheel is always the same at the grinding point. The wheel should be run in the direction indicated by the arrow; then the action of the wheel will tend to hold the tooth upon the rest. Angular or taper cutters, such as shown in igs. 63 and 64, may be ground by holding them on a mandrel, as in Fig. 60, but the swivel table must be set over for the proper taper. When the taper of the cutter is greater than two inches per foot, the feeding may be done with the cross-feed, and the wheel set as shown in and ex- plained in connection with Fig. 46. The side teeth of a cutter, Fig. 61 for example, may be ground ona Universal Grinding Machine, but the way 118 BROWN & SHARPE MFG. CO. machine is not recommended for such a purpose, as, in order to obtain the proper clearance, the wheel stand must be elevated so that the centre of the wheel will be above the tooth rest; the tooth rest, in this case, having to be set as high as the centre of the head stock spindle. Where many cutters of this class have to be ground, or in fact for manufacturing establishments having a great deal of tool grinding we would recommend our special tool and cutter grinding machines as more convenient and economical. Special Our Nos. 1 and 2 Tool Grinders and No. 3 Cutter aries and Reamer Grinder are illustrated and described in Machineryour catalogue, and the No. 3 Universal Cutter and Reamer Grinder is more completely described and a number of its operations are shown ina special pam- phlet, which is mailed, with the catalogue, to any ad- dress on application, BROWN & SHARPE MFG. CO. 11g GAUGES AND CALIPERS. Next in importance to a machine, which is directly used to produce true and accurate work, come the supplementary tools used in testing and determining the dimensions of the work, It is evident that unless these are accurate and trustworthy, there can be no certainty as to the true quality of the work which is tested by them. In the following pages we illustrate some of the measuring tools, manufactured at our works, which are well adapted.to a large variety of work in connection with our grinding machines, as well as for general machine shop use. Fig. 65 illustrates our Standard Caliper. Gauges which are hardened and ground to the sizes marked onthe ee side of the gauge. Oneend is adapted to outside and the Gauges. other to inside calipering. The use of these gauges has the effect of eliminating, in a large degree, the personal differences in measuring work with ordinary calipers, and therefore results in a greater uniformity in the production of machine parts, These gauges are made in sizes from one-quarter to two and a half inches, varying by sixteenths up to two inches, and above that by eighths. Every full set is neatly arranged in a suitable box. Special sizes are usually made to order. Standard Cylindrical Gauges shown in Fig. 66, are Standard arranged in sets, ranging in size from three-sixteenths “Yay to two inches diameter, varying by sixteenths, Other sizes are usually made to order. They are very con- venient for ordinary machine work, as calipers can be 120 BROWN & SHARPE MIG, CO. FIG. 68. BROWN & SHARPE MFG, CO, 121 FIG, 69. FIG. 70. | [3 a dhobulr hl 122 Standard Internal and BROWN & SHARPE MFG. CO. set and diameters transferred from them much more accurately than from a rule. For measuring work internally these gauges can be used directly, without the use of calipers. The more costly Standard Internal and External Cylindrical Gauges are illustrated in Figs. 67 and 68. External They are arranged in boxes in sets ranging in size from Cylindrical Gauges. Standard Reference Disks. Caliper Squares. Vernier Calipers one-quarter to two inches in diameter, and varying by sixteenths. The sizes are stamped on the handles as shown, both in common and decimal fractions. The Standard Reference Disks, Fig. 69, are used, generally without handles, for setting calipers, testing measuring tools, and reference for sizes in shop practice. With handles, they are used in place of Standard Cylindrical Gauges, but are not recommended for con- stant use as substitutes for these, ‘They are designed to serve principally as reference, not as working gauges, A complete set consists of 45 disks, varying by 16ths of an inch, from } inch to 3 inches diameter, and six handles. A suitable box is furnished with each com- plete set of disks and handles. The Caliper Square shown in Fig. 70 is a convenient tool for ordinary use, It is graduated on one side, to sixty-fourths, and on the other to hundredths, There are different sizes of these tools, varying from two to nine inches in length, either with or without the adjust- ing screw. ; For accurate measurements, the Vernier Calipers, “illustrated in Figs. 71, 72 and 73, are very convenient, as they can be readily set to any desired distance, and the jaws are adapted to both outside and inside measurements, They are divided to read to the thousandth part of an inch on one side, and on the other to sixty-fourths, or to the one-fiftieth part of a millimeter (Jy m. m. = (0007874 inch), as may be desired. The one shown in Fig. 71 is about three and five-eighths inches long and will measure, between the jaws, when fully open, one inch and eleven-sixteenths. ‘This makes a convenient size to carry in the pocket. The caliper, BROWN & SHARPE MFG. CO. 123 FRONT SIDE. ee Fig. 26 isa fac-simile of one side of the Vernier Gollbety which reads to thousandths of inches. On the other side (Fig. 27) are 6iths or 50ths of inches, to read without a Vernier. This instrument is furnished with both inside and outside cal paia and points to transfer the distance with dividers. An explanation of the Vernier accompanies each instrument. These instruments are made of steel, and have the points temper- ed and jaws ground. Price, in Morocco Case—6 in. $20; 12 in. 3 24 in. $30. BACK SIDE. nam Fig. 73. 124 Microme- ter Calipers. BROWN & SHARPE MFG. CO, shown in Figs. 72 and 73 is a larger size and is made of different lengths, from six to twenty-four inches. Fig. 72 shows the side which reads to thousandths, and Fig. 73 the other side, which is divided to sixty-fourths, or French measure, if desired, Directions for reading and setting the caliper by the vernier accompany every instrument, Perhaps the most convenient and accurate instru- ments for small external measurements are the Micro- meter Calipers shown, full size, in Figs. 74 to 83, The smallest measures all sizes up to one-half inch and the largest, all sizes up to two inches. They are graduatde to read to thousandths of an inch, but one-half and one-quarter thousandths are readily estimated. Some of the calipers have verniers by which sizes can be obtained to ten-thousandths. We also graduate some of these instruments to read to hundredths of a millimeter instead of to thousandths of an inch, When they are so graduated the tables of decimal equivalents are omitted. The gauge screws are encased, and protected from dirt and liability to injury. The parts most subject to wear are hardened, and means of adjustment are pro- vided to compensate for wear of the screw or nut. The decimal equivalents stamped on the frame are very convenient, and render possible the immediate expres- sion of readings in eighths, sixteenths, thirty-seconds and sixty-fourths. The chief mechanical principle embodied in the construction is that of a screw free to move ina fixed nut. An opening, to receive the work to be measured, is afforded by the backward movement of the screw, and the size of the opening is indicated by the gradua- tions. The pitch of the screw is forty to the inch, The graduation of the hub, in a line parallel to the axis of the screw, is forty to the inch, and is figured, 0, 1, 2, etc., every fourth division. As the graduation conforms to the pitch of the screw, each division equals the BROWN & SHARPE MFG. CO. FIG. 75. “exer tc test 6z SN gSTs’ cc stzv zz * goss" sc TeeTezwermd 906c" Se 4996" TE SLEG St 2506 62 Sete er FIG. 77. BROWN & SHARPE MFG. CO. 2996" TC SLES" st 2908" 6z SZra" et LE0e 42 -pgasuspuag S189" TT wl mogy SEIS” 6 oduoimess unig $2956 \ zrel sz “ate e@ z9so" tz Lees’ 6T eres ZT “3o% 2896" TE SLEG ct § 2906" 6e Sere et ZE0S LE -rz-aouspuoig SL89° TT f eter se “ete ce zoso 2 4e6S" 6t eres’ ZT cog 3ytadmyg gum SEIS 6 am Fe Cer FIG. 79. FIG, 78. S MAG sles st S = fee. Shee tr a LE5! Te eouapuasy \ Zier sz rnoig SZ9S" 6 Ci E810" ce SOUS TUE ETT \ zoso" ete’ ¢ LE6S' oT ae © eres’ £T seso 7 £899 ST . : =U oT