MACHINE  TOOLS The machine tools employed in See also:

• MODERN

modern See also:

• ENGINEERING

engineering factories number many hundreds of well-defined and See also:

• SEPARATE

separate types . Besides these, there are hundreds more designed for See also:

• SPECIAL

special functions, and adapted only to the See also:

• WORK

work of firms who handle specialities . Most of the first named and many of the latter admit of grouping in classes . The following is a natural See also:

• CLASSIFICATION (Lat. classis, a class, probably from the root cal-, cla-, as in Gr. icaMce, clamor)

classification: I . Turning Lathes.—These, by See also:

• COMMON

common consent, stand as a class alone . The See also:

• CARDINAL (Lat. cardinalis)

cardinal feature by which they are distinguished is that the work being operated on rotates against a See also:

• TOOL (0. Eng. tdl, generally referred to a root seen in the Goth. taujan, to make, or in the English word " taw," to work or dress leather)

tool which is held in a rigid fixture—the See also:

• REST (O. Eng. rest, reste, bed, cognate with other Teutonic forms, e.g. Ger. Rast, Riiste, rest, and probably Gothic Rasta, league, i.e. resting or stopping place)

rest . The See also:

• AXIS (Lat. for " axle ")

axis of rotation may be See also:

• HORIZONTAL

horizontal or See also:

• VERTICAL (from Lat. vertex, highest point)

vertical . II . Reciprocating See also:

• MACHINES

Machines.—The feature by which these are characterized is that the relative movements of tool and work take See also:

• PLACE (through Fr. from Lat. platea, street; Gr. IrAar6s, wide)

place in straight lines, to and fro . The reciprocations may occur in horizontal or vertical planes . IV . Milling Machines.—This See also:

• GROUP

group uses cutters having See also:

• TEETH (O.E. Eel); plural of tooth, O.E. top)

teeth arranged equidistantly See also:

• ROUND (O. Fr. rond, Lat. rotundus, the Fr. is the source also of Du. rond; Ger., Swed., Dan. and Nor. rond)

round a cylindrical See also:

• BODY

body, and may therefore be likened to saws of considerable thickness .

The cutters rotate over or against work, between which and the cutters a relative See also:

• MOVEMENT

movement of travel takes place, and they may therefore be likened to reciprocating machines, in which a revolving cutter takes the place of a single-edged one . V . Machines for Cutting the Teeth of See also:

• GEAR (connected with " garb," properly elegance, fashion, especially of dress, and with " gar," to cause to do, only found in Scottish and northern dialects; the root of the word is seen in the Old Tent. garwjan, to make ready)

Gear-wheels.—These comprise two sub-See also:

• GROUPS
• GROUPS, THEORY

groups, the older type in which rotary milling cutters are used, and the later type in which reciprocating single-edged tools are employed . Sub-classes are designed for one See also:

• KIND (O. E. ge-cynde, from the same root as is seen in " kin," supra)

kind of gear only, as See also:

• SPUR (A.S. spura, spora, related to spornan, spurnan, to kick, spurn; cf. M.H.G. sporn, mod. Ger. Sporn)

spur-wheels, bevels, See also:

• WORMS

worms, racks, &c . VI . Grinding Machinery.—This is a large and constantly extending group, largely the development of See also:

• RECENT

recent years . Though See also:

• EMERY (Ger. Smirgel)

emery grinding has been practised in crude See also:

• FASHION (adapted from Fr. facon, agon, Lat. factio, making, facere, to do or make)

fashion for a See also:

• CENTURY (from Lat. centuria, a division of a hundred men)

century, the difference in the old and the new methods lies in the embodiment-of the grinding See also:

• WHEEL (0. Eng. hweol, hweohl, &c., cognate with Icel. hjol, Dan. hiul, the Indo-European root is seen in Sanskrit chakra, Gr. r in Aos, circle, whence " cycle ")
• WHEEL, BREAKING ON THE

wheel in machines of high precision, and in the rivalry of the wheels of See also:

• CORUNDUM

corundum, See also:

• CARBORUNDUM

carborundum and alundum, prepared in the electric See also:

• FURNACE

furnace with those of emery . IX . Hammers and Presses.—Here there is a percussive See also:

• ACTION

action in the hammers, and a purely squeezing one in the presses . Both are made capable of exerting immense pressures, but the latter are far more powerful than the former . X . Portable Tools.—This large group can best be classified by the common feature of being readily removable for operation on large pieces of erection that cannot be taken to the See also:

• REGULAR

regular machines .

Hence they are all comparatively small and See also:

• LIGHT

light . Broadly they include diverse tools, capable of performing nearly the whole of the operations summarized in the pre-ceding paragraphs . XI . Appliances.—There is a very large number of articles which are neither tools nor machine tools, but which are in-dispensable to the work of these; that is, they do not cut, or shape, or See also:

• MOULD

mould, but they hold, or grip, or See also:

• CONTROL (Fr. contrdle, older form contre rolle, from Med. Lat. contra-rotulus, a counter roll or copy of a document used to check the original; there is no instance in English of the use of " control " in this, its literal, meaning)

control, or aid in some way or other the carrying through of the work . Thus a See also:

• SCREW (O.E. scrue, from O. Fr. escroue, mod. ecrou; ultimate origin uncertain; the word, or a similar one, appears in Teutonic languages, cf. Ger. Schraube, Dan. skrue, but Skeat, following Diaz, finds the origin in Lat. scrobs, a ditch, hole, particularl

screw wrench, an See also:

• ANGLE (from the Lat. angulus, a corner, a diminutive, of which the primitive form, angus, does not occur in Latin; cognate are the Lat. angere, to compress into a bend or to strangle, and the Gr. ayKOS, a bend; both connected with the Aryan root ank-, to

angle See also:

• PLATE

plate, a See also:

• WEDGE (O. Eng. wecg, a mass of metal, cognate with Dutch wig, wigge, Dan. vaegge, &c.; in Lith. the cognate form outside Teut. is found in wagis, a peg, spigot; there is no connexion with " weigh," " weight," which must be referred to the root wegh, to li

wedge, a piece of packing, a See also:

• BOLT

bolt, are appliances . In modern practice the appliance in the See also:

• FORM (Lat. forma)

form of a templet or See also:

• JIG

jig is one of the See also:

• PRINCIPAL

principal elements in the interchangeable See also:

• SYSTEM

system . I.-LATHES1 The popular conception of a See also:

• LATHE

lathe, derived from the See also:

• FAMILIAR (through the Fr. familier, from Lat. familiaris, of or belonging to the familia, family)

familiar machine of the See also:

• WOOD, ANTHONY A2 (1632-1695)
• WOOD, JOHN GEORGE (1827—1889)
• WOOD, MRS HENRY [ELLEN] (1814—1887)
• WOOD, SEARLES VALENTINE (1798—188o)

wood See also:

• TURNER, CHARLES (1773–1857)
• TURNER, JOSEPH MALLORD WILLIAM (1775–1851)
• TURNER, NAT (1800-1831)
• TURNER, SHARON (1768-1847)
• TURNER, SIR JAMES (1615–1686)
• TURNER, WILLIAM (d. 1568)

turner, would not give a correct See also:

• IDEA (Gr. Ibia, connected with i&eiv, to see; cf. Lat. species from specere, to look at)

idea of the lathe which has been See also:

• DEVELOPED

developed as the engineer's machine tool . This has become differentiated into nearly fifty well-marked,types, until in some cases even the See also:

• TERM

term lathe has been dropped for more precise See also:

• DEFINITIONS

definitions, as vertical See also:

• BORING

boring machine, automatic machine, while in others prefixes are necessary, as See also:

• AXLE (in Mid. Eng. axel-tre, from O. Norweg. oxull-tre, cognate with the O. Eng. exe or eaxe, and connected with Sansk. dksha, Gr. a wv, and Lat. axis)

axle lathe, chucking lathe, cutting-off lathe, wheel lathe, and so on . With regard to See also:

• SIZE

size and See also:

• MASS (O.E. maesse; Fr. messe; Ger. Messe; Ital. messa; from eccl. Lat. missa)
• MASS, IN

mass the height of centres may range from $ in. in the See also:

• BENCH (an O.E. and Eng. form of a word common to Teutonic languages, cf. Ger. Bank, Dan. baenk and the Eng. doublet " bank ")

bench lathes to 9 or to ft. in See also:

• GUN

gun lathes, and weights will range from say 5o lb to 200 tons, or more in exceptional cases . While in some the mechanism is the simplest possible, in others it is so complicated that only the specialist is able to grasp its details . See also:

• EARLY
• EARLY, JUBAL ANDERSON (1816-1894)

Early Lathes.—Space will not permit us to trace the See also:

• EVOLUTION

evolution of the lathe from the See also:

• ANCIENT
• ANCIENT (also spelt ANTIENT; derived, through the Fr. ancien, old, from the late Lat. antianum, from ante, before)

ancient See also:

• BOW (pronounced " bo ")

bow and card lathe and the See also:

• POLE (FAMILY)
• POLE, REGINALD (1500-1558)
• POLE, RICHARD DE LA (d. 1525)
• POLE, WILLIAM (1814—1900)

pole lathe, in each of which the rotary movement was alternately for-See also:

• WARD
• WARD, ADOLPHUS WILLIAM (1837- )
• WARD, ARTEMUS
• WARD, EDWARD MATTHEW (1816-1879)
• WARD, ELIZABETH STUART PHELPS (1844-1911)
• WARD, JAMES (1769--1859)
• WARD, JAMES (1843– )
• WARD, JOHN QUINCY ADAMS (1830-1910)
• WARD, LESTER FRANK (1841– )
• WARD, MARY AUGUSTA [MRS HUMPHRY WARD]
• WARD, WILLIAM (1766-1826)
• WARD, WILLIAM GEORGE (1812-1882)

ward, for cutting, and backward . The curious thing is that the wheel-driven lathe was a novelty so See also:

• LATE

late as the 14th and 15th centuries, and had not wholly displaced the ancient forms even in the See also:

• WEST
• WEST, BENJAMIN (1738-1820)
• WEST, NICHOLAS (1461-1533)

West in the 19th century, and the See also:

• CORD (derived through the Fr. corde, from the Lat. chorda, Gr. xop(5rt, the string of a musical instrument)

cord lathe still survives in the See also:

• EAST
• EAST, ALFRED (1849- )

East .

Another thing is that all the old lathes were of dead centre, instead of See also:

• RUNNING

running mandrel type; and not until 1794 did the use of See also:

• METAL
• METAL (through Fr. from Lat. metallum, mine, quarry, adapted from Gr. µATaXAov, in the same sense, probably connected with ,ueraAAdv, to search after, explore, µeTa, after, aAAos, other)

metal begin to take the place of wood in lathe construction . See also:

• HENRY
• HENRY (1129-1195)
• HENRY (c. 1108-1139)
• HENRY (c. 1174–1216)
• HENRY (Fr. Henri; Span. Enrique; Ger. Heinrich; Mid. H. Ger. Heinrich and Heimrich; O.H.G. Haimi- or Heimirih, i.e. " prince, or chief of the house," from O.H.G. heim, the Eng. home, and rih, Goth. reiks; compare Lat. rex " king "—" rich," therefore " mig
• HENRY, EDWARD LAMSON (1841– )
• HENRY, JAMES (1798-1876)
• HENRY, JOSEPH (1797-1878)
• HENRY, MATTHEW (1662-1714)
• HENRY, PATRICK (1736–1799)
• HENRY, PRINCE OF BATTENBERG (1858-1896)
• HENRY, ROBERT (1718-1790)
• HENRY, VICTOR (1850– )
• HENRY, WILLIAM (1795-1836)

Henry Maudslay (1771–1831) did more than any other See also:

• MAN
• MAN, ISLE OF (anc. Mona)

man to develop the engineer's self-acting lathe in regard to its essential mechanism, but it was, like its immediate successors for fifty years after, a See also:

• SKELETON

skeleton-like, inefficient weakling by comparison with the lathes of the See also:

• PRESENT

present See also:

• TIME (0. Eng. Lima, cf. Icel. timi, Swed. timme, hour, Dan. time; from the root also seen in " tide," properly the time of between the flow and ebb of the sea, cf. O. Eng. getidan, to happen, " even-tide," &c.; it is not directly related to Lat. tempus)
• TIME, MEASUREMENT OF
• TIME, STANDARD

time . Broad Types.—A ready appreciation of the broad See also:

• DIFFERENCES, CALCULUS OF (Theory of Finite Differences)

differences in lathe types may be obtained by considering the differences in the See also:

• GREAT

great groups of work on which lathes are designed to operate . Castings and forgings that are turned in lathes vary not only in size, but also in relative dimensions . Thus a See also:

• LONG, GEORGE (1800-1879)
• LONG, JOHN DAVIS (1838– )

long piece of See also:

• DRIVING (from " to drive," i.e. generally to propel, force along or in, a word common in various forms to the Teutonic languages)

driving shafting, or a railway axle, is very differently proportioned in length and See also:

• DIAMETER (from the Cr. &a, through, µErpov, measure)

diameter from a railway wheel or a wheel See also:

• TIRE

tire . Further, while the See also:

• SHAFT
• SHAFT (O. Eng., sceaft, from scafan, to shave; the word is common to Teutonic languages)

shaft has to be turned only, the wheel or the tire has to be turned and bored . Here then we have the first cardinal distinction between lathes, viz. those admitting work between centres (fig . 29) and See also:

• FACE (from Lat. fades, derived either from facere, to make, or from a root fa-, meaning " appear "; cf. Gr. cbatvstv)

face and boring lathes . In the first the piece of work is pivoted and driven between the centres of See also:

• HEAD (in 0. Eng. heafad; the word is common to Teutonic languages; cf. Dutch hoofd, Ger. Haupt, generally taken to be in origin connected with Lat. caput, Gr. KerbOvi7)
• HEAD, SIR EDMUND WALKER, BART
• HEAD, SIR FRANCIS BOND, BART

head-stock and tail-stock or loose poppet; in the second, it is held and gripped only by the See also:

• DOGS, ISLE OF

dogs or jaws of a face-plate, on the head-stock spindle, the loose poppet being omitted . These, however, are broad types only, since proportions of length to diameter differ, and with them lathe designs are modified whenever there is a sufficient amount of work of one class to justify the laying down of a special machine or machines to See also:

• DEAL

deal with it . Then further, we have duplicate designs, in which, for example, See also:

• PROVISION (Lat. provisio)

provision is made in one lathe for turning two or three long shafts simultaneously, or for turning and boring two wheels or tires at once . Further, the position of the axis of a face lathe need not be horizontal, as is necessary when the turning of long pieces has to be done between centres .

There are obvious advantages in arranging it vertically, the principal being that castings and forgings can be more easily set and secured to a horizontal chuck than to one the face of which lies vertically . The chuck is also better sup-ported, and higher rates of turning are practicable . In recent years these vertical lathes or vertical turning and boring See also:

• MILLS, JOHN (d. 1736)
• MILLS, ROGER QUARLES (1832– )

mills (fig . 30) have been greatly increasing in See also:

• NUMBERS, BOOK OF
• NUMBERS, PARTITION OF

numbers; they also occur in several designs to suit either See also:

• GENERAL
• GENERAL (Lat. generalis, of or relating to a genus, kind or class)

general or special duties, some of them being used for boring only, as chucking lathes . Some are of immense size, capable of boring the See also:

• FIELD (a word common to many West German languages, cf. Ger. Feld, Dutch veld, possibly cognate with O.E. f olde, the earth, and ultimately with root of the Gr. irAaror, broad)
• FIELD, CYRUS WEST (1819-1892)
• FIELD, DAVID DUDLEY (18o5-1894)
• FIELD, EUGENE (1850-1895)
• FIELD, FREDERICK (18o1—1885)
• FIELD, HENRY MARTYN (1822-1907)
• FIELD, JOHN (1782—1837)
• FIELD, MARSHALL (183 1906)
• FIELD, NATHAN (1587—1633)
• FIELD, STEPHEN JOHNSON (1816-1899)
• FIELD, WILLIAM VENTRIS FIELD, BARON (1813-1907)

field magnets of electric generators 40 ft. in diameter . See also:

• STANDARD
• STANDARD, BATTLE OF THE

Standard Lathes.—But for doing what is termed the general work of the engineer's turnery, the standard lathes (fig . 29) predominate, i.e. self-acting, sliding and surfacing lathes with headstock, loose poppet and slide-rest, centres, face plates and chucks, and an equipment by which long pieces are turned, either between centres or on the face chucks, and bored . One of the greatest objections to the employment of these standard types of lathes for indiscriminate See also:

• DUTY (from " due," that which is owing, O. Fr. deu, dil, past participle of devoir; Lat. debere, debitum; cf. " debt ")

duty is due to the limited height of the centres or axis of the head-stock, above the face of the See also:

• BED
• BED (a common Teutonic word, cf. German Bett, probably connected with the Indo-European root bhodh, seen in the Lat. fodere, to dig; so " a dug-out place " for safe resting, or in the same sense as a garden " bed ")

bed . This is met generally by providing a See also:

• GAP

gap or deep See also:

• RECESS (Lat. recessus, a going back, withdrawal, from recedere, to withdraw)

recess in the bed next the fast headstock, deep enough to take face work of large diameter . The See also:

• DEVICE

device is very old and very common, but when the See also:

• VOLUME

volume of work warrants the employment of separate lathes for face-work and for that done between centres it is better to have them . Screw-cutting.—A most important See also:

• SECTION
• SECTION (Lat. sectio, cutting, secare, to cut)

section of the work of the engineer's turnery is that of cutting screws (see SCREW) . This has resulted in differentiation fully as great as that existing between centres and face-work .

The slide-rest was designed with this See also:

• OBJECT

object, though it is also used for See also:

• PLAIN (O. Fr. plain, from Lat. plenum)

plain turning . The standard " self-acting sliding, surfacing and screw-cutting lathe " is essentially the standard turning lathe, with the addition of the screw-cutting mechanism . This includes a See also:

• MASTER (Lat. magister, related to tnagis, more, as the corresponding minister is to minus, less; the English form is due partly to the O. Eng. maegister, and partly to O. Fr. maistre, mod. maitre; cf. Du. meester, Ger. Meister, Ital. maestro)

master screw—the See also:

• LEAD
• LEAD (pronounced iced)

lead or See also:

• GUIDE (in Mid. Eng. gyde, from the Fr. guide; the earlier French form was guie, English " guy," the d was due to the Italian form guida; the ultimate origin is probably Teutonic, the word being connected with the base seen in O. Eng. witan, to know)

guide screw, which is gripped with a clasp See also:

• NUT
• NUT (0. Eng. knutu, cf. Dutch noot, Ger. Nuss; allied with Gael. cno; it is not of the same form as Lat. nux)

nut, fastened to the travelling See also:

• CARRIAGE

carriage of the slide-rest . The lead-screw is connected to the headstock spindle by See also:

• CHANGE (derived through the Fr. from the Late Lat. cambium, cambiare, to barter; the ultimate derivation is probably from the root which appears in the Gr. «a urmu', to bend)

change wheels, which are the variables through which the relative rates of movement of the spindle and the lead-screw, and therefore of the screw-cutting tool, held and traversed in the slide-rest, are effected . By this beautiful piece of mechanism a guide screw, the See also:

• PITCH
• PITCH, MUSICAL

pitch of which is permanent, is made to cut screw-threads of an almost See also:

• INFINITE (from Lat. in, not, finis, end or limit; cf. findere, to deave)

infinite number of possible pitches, both in whole and fractional numbers, by virtue of rearrangements of the variables, the change wheels . The objection to this method is that the trains of change wheels have to be recalculated and rearranged as often as a screw of a different pitch has to be cut, an operation which takes some little time .. To avoid this, the See also:

• NEST

nest or cluster system of gears has been largely adopted, its most successful embodiment being in the Hendey-See also:

• NORTON, CAROLINE ELIZABETH SARAH (18o8–1877)
• NORTON, CHARLES BOWYER ADDERLEY, 1ST BARON (1814–1905)
• NORTON, CHARLES ELIOT (1827-1908)
• NORTON, THOMAS (1532–1584)

Norton lathe . Here all the change wheels are arranged in a See also:

• SERIES (a Latin word from serere, to join)

series permanently on one shaft underneath the headstock, and any one of them is put into engagement by a sliding pinion operated by the See also:

• SIMPLE

simple movement of a See also:

• LEVER (through O. Fr. leveour, levere, mod. levier, from Lat. levare, to lift, raise)
• LEVER, CHARLES JAMES (1806-1872)

lever . Thus the lead-screw is driven at different rates without removing any wheel from its spindle . This has been extensively applied to both small and large lathes . But a moment's thought will show that even this device is too cumbrous when large numbers of small screws are required . There is, for example, little in common between the screw, say of 5 or 6 ft. in length, for a massive penstock or See also:

• VALVE (Lat. valva, a leaf of a double or folding door, allied to volvere, to roll, as of a door on its hinges)

valve, and 2-in. bolts, or the small screws required in thousands for See also:

• ELECTRICAL
• ELECTRICAL (or ELECTROSTATIC) MACHINE

electrical fittings .

Clearly while the self-acting screw-cutting lathe is the best possible machine to use for the first, it is unsuitable for the last . So here at once, from the point of view of screw cutting only, an important divergence takes place, and one which has ultimately led to very high specialization . Small Screws.—When small screws and bolts are cut in large quantities, the guide-screw and change wheels give place to other devices, one of which involves the use of a separate master-screw for every different pitch, the other that, of encircling cutting See also:

• INSTRUMENTS

instruments or See also:

• DIES, CHRISTOPH ALBERT (1755-1822)

dies . The first are represented by the See also:

• CHASING, or ENCHASING

chasing lathe, the second by the screwing lathes and automatics . Though the principles of operation are thus stated in brief, the details in See also:

• DESIGN (Fr. desiin, drawing; Lat. designare, to mark out)

design are most extensive and varied . In a chasing lathe the master-screw or hob, which may be either at the See also:

• REAR

rear of the headstock or in front of the slide-rest, receives a hollow clasp-nut or a See also:

• HALF

half-nut, or a See also:

• STAR

star-nut containing several pitches, which, partaking of the See also:

• TRAVERSE

traverse movement of the screw-See also:

• THREAD (0. Eng. praed, literally, that which is twisted, prawan, to twist, to throw, cf. " throwster," a silk-winder, Ger. drehen, to twist, turn, Du. draad, Ger. Draht, thread, wire)

thread, imparts the same horizontal movement to the cutting tool . The latter is sometimes carried in a hinged holder, sometimes in a common slide-rest . The attendant throws it into engagement at the beginning of a traverse, and out when completed, and alsothis is an economical system, but in others not . It cannot be considered so when bolts, screws and allied forms are of small dimensions . Hollow Mandrel Lathes.—It has been the growing practice since the last See also:

• DECADE (from Gr. Oka, ten)

decade of the 19th century to produce See also:

• SHORT, FRANCIS JOB (1857– )

short articles, required in large quantities, from a long See also:

• BAR
• BAR (0. Fr. barre, Late Lat. barra, origin unknown)
• BAR, CONFEDERATION OF
• BAR, FRANCOIS DE (1538-1606)
• BAR, THE

bar . This involves making the lathe with a hollow mandrel; that is, the mandrel of the head-stock has a hole drilled right through it, large enough to permit of the passage through it of the largest bar which the class of work requires . Thus, if the largest section of the finished pieces should require a bar of i 2 in. diameter, the hole in the mandrel would be made 18 in .

Then the bar, inserted from the rear-end, is gripped 3y a chuck or collet at the front, the operations of turning, screwing and cutting off done, and the bar then thrust farther through to the exact length for the next set of identical operations to be A, Table, running with See also:

• STEM (O. Eng. staefn, stemn, cf. Du. stain, Ger. Stamm, &c., probably related to " staff ")

stem in vertical bearing . B, See also:

• FRAME

Frame of machine . C, Driving cones . D, Handle giving the choice of two rates, through concealed sliding gears, shown dotted . E, See also:

• BEVEL (from an O. Fr. word, cf. mod. biveau, a joiner's instrument)

Bevel-gears driving up to pinion gearing with See also:

• RING (O.E. hring; a word common to Teutonic languages; and probably cognate with the Lat. circus, Gr. KtpKOS or KpLKOS, Skt'. chakra, wheel, circle, cf. also " harangue "); in art, a band of circular shape of varying sizes, made of any material and used f

ring of teeth on the table . F, See also:

• SADDLE (a word common to Teutonic languages, cf. Ger. Sattel, Dut. zadel, also in Russ. siedlo and Lat. sella, for sedla; it is not derived directly from Lat. sedile, which means a chair, but all the words are to be referred to the root sad-, which gives

Saddle moved on See also:

• CROSS

cross-See also:

• RAIL

rail G . changes the hobs for threads of different sections . The screwed stays of See also:

• LOCOMOTIVE

locomotive See also:

• FIRE (in O. Eng. f j'r; the word is common to West German languages, cf. Dutch vuur, Ger. Feuer; the pre-Teutonic form is seen in Sanskrit pu, pavaka, and Gr. irup; the ultimate origin is usually taken to be a root meaning to purify, cf. Lat. purus)

fire-boxes are almost invariably cut on chasing lathes of this class . In the screwing machines the thread is cut with dies, which encircle the rotating bar; or alternatively the dies rotate round a fixed See also:

• PIPE

pipe, and generally the angular lead or advance of the thread draws the dies along . These dies differ in no essentials from similar tools operated by a See also:

• HAND
• HAND (a word common to Teutonic languages; cf. Ger. Hand, Goth. handus)
• HAND, FERDINAND GOTTHELF (1786-185r)

hand lever at the bench . There are many modifications of these lathes, because the work is so highly specialized that they are seldom used for anything except the work of cutting screws varying but little in dimensions . Such being the See also:

• CASE
• CASE, JOHN (d. 1600)

case they can hardly be classed as lathes, and are often termed screwing machines, because no provision exists for preliminary turning work, which is then done elsewhere, the task of turning and threading being divided between two lathes .

In some caseslathe . (See also:

• WEBSTER
• WEBSTER, ALEXANDER (1707-1784)
• WEBSTER, BENJAMIN NOTTINGHAM (1797-1882)
• WEBSTER, DANIEL (1782-1852)
• WEBSTER, JOHN (fl. 1602-1624)
• WEBSTER, NOAH (1758-1843)
• WEBSTER, THOMAS (1773-1844)
• WEBSTER, THOMAS (1800-1886)

Webster See also:

• BENNETT, CHARLES EDWIN (1858- )
• BENNETT, JAMES GORDON (1794-1872)
• BENNETT, JOHN
• BENNETT, JOHN HUGHES (1812–1875)
• BENNETT, SIR WILLIAM STERNDALE (1816-1875)

Bennett, Ltd., See also:

• COVENTRY, SIR JOHN (d. 1682)
• COVENTRY, SIR WILLIAM (c. 1628-1686)
• COVENTRY, THOMAS COVENTRY, 1ST BARON (2578–1640)

Coventry.) H, Vertical slide, carrying See also:

• TURRET (from O. Fr. tourette, diminutive of tour, tower, mod. Fr. tourelle)

turret J . K, Screw feeding F across . L, Splined shaft connecting to H for feeding the latter up or down . M, M, See also:

• WORM

Worm-gears throwing out clutches N, N at predetermined points . 0, See also:

• CONE (Gr. Kwvos)

Cone See also:

• PULLEY

pulley belted up to P, for driving the feeds of saddle and down-slide . performed, and so on . This mechanism is termed a See also:

• WIRE (A.S. wir, a wire; cf. Swed. vire, to twist, M.H.G. wiere, a gold ornament, Lat. viriae, armlets, ultimately from the root wi, to twist, bind)

wire feed, because the first lathes which were built of this type only operated on large wires; the heavy bar lathes have been subsequently developed from it . In the more advanced types of lathes this feeding through the hollow spindle does not require the intervention of the attendant, but is performed automatically . The amount of preliminary work which has to be done upon a portion of a bar before it is ready for screwing varies . The simplest object is a See also:

• STUD

stud, which is a parallel piece screwed up from each end . A bolt is a screw with a head of hexagonal, square or circular form, and the See also:

• PRODUCTION (Lat. productionem, from producere, to pro-duce)

production of this involves turning the shank and See also:

• SHOULDER (in O.E. sculder, cognate with Ger. Schulter, Dutch schouder, Swed. skuldra, &c; the root is unknown)

shoulder and imparting convexity to the end, as well as screwing .

But screw-threads have often to be cut on See also:

• OBJECTS

objects which are not primarily bolts, but which are spindles of various kinds used on mechanisms and machine tools, and in which reductions in the form of steps have to be made, and recesses, or flanges, or other features Turret Lathes.—The turret or See also:

• CAPSTAN (also spelt in other forms, or as " capstock " and " cable stock," connected with the O. Fr. capestan or cabestan, from Lat. capistrum, a halter, capere, to take hold of; the conjecture that it came from the Span. cobra, goat, and estanto, standin

capstan (fig . 32) is a device for grippsoduced . Out of the demands for this more complicated work, ping as many separate tools as there are distinct operations to be as well as for plain bolts and studs, has arisen the great group of turret or capstan lathes (fig . 31) and the automatics or automatic screw machines which are a high development of the turret lathes . performed on a piece of work; the number ranges from four to as many as twenty in some highly elaborated machines, but five or six is the usual number of holes . These tools are brought round RlKLANMUt Wa nm . _FIG . 31.—Turret, Lathe . ° ... Webster & Bennett, Ltd., Coventry.) A, Bed . N, Bearing to feed the work through mandrel (constituting the B, See also:

• WASTE (O. Fr. wast, guast, gast, gaste; Lat. vastus, vast, desolate)

Waste oil See also:

• TRAY

tray. wire or bar feed) . A See also:

• COLLAR

collar is clamped on the work, and is C, Headstock. pushed by the bearing N at each time of feeding .

Hollow 0, Cross-slide . mandrel . D, P, Hand-wheel operating screw to travel O . E, Cones keyed to D . F, Split tapered See also:

• CLOSE
• CLOSE (from Lat. clausum, shut)
• CLOSE, MAXWELL HENRY (1822-1903)

close-in chuck, actuated by See also:

• TUBE (Lat. tuba)

tube G . Q, Turret-slide . H, Toggle dogs which push G . R, Cross-handle moving Q to and fro . J, Coned collar acting on H . S, Turret or capstan . K, Handle to slide J through See also:

• SLEEVE (O. Eng. slieve, slyf, a word allied to " slip," cf. Dutch sloof, apron)

sleeve on bar L . T, U, Sets of fast and loose pulleys, for open and crossed belts .

M, See also:

• RACK

Rack slid on See also:

• RELEASE (O.Fr. reles, variant of relais, from relaisser, to release, let go, Lat. relaxare)

release of chuck, moving bearing N forward . V, Cone belted down to E on lathe . in due See also:

• SUCCESSION (Lat. successio, from succedere, to follow after)

succession, each one doing its little See also:

• SHARE (O. Eng. scearu, chiefly in compounds, e.g. land-scearu, a share of land, from sceran to cut; cf. " shear" )

share of work, until the See also:

• CYCLE
• CYCLE (Gr. KUK)^os, a circle)

cycle of operations required to produce the object is See also:

• COMPLETE

complete, the cycle including such operations as turning and screwing, roughing and See also:

• FINISHING

finishing cuts, drilling and boring . Severance of the finished piece is generally done by a tool or tools held by a cross-slide between the headstock and turret, so termed because its movements take place at right angles with the axis of the machine . This also often performs the duty of " forming," by which is meant the shaping of the exterior portion of an object of irregular outline, by a tool the edge of which is an exact counterpart of the See also:

• PROFILE

profile required . The exterior of a cycle hub is shaped thus, as also are numerous handles and other objects involving various curves and shoulders, &c . The tool is fed perpendicularly to the axis of the rotating work and completes outlines at once: if this were done in See also:

• ORDINARY (med. Lat. ordinarius, Fr. ordinaire)

ordinary lathes much tedious manipulation of separate tools would be involved . Automatics.—But the marvel of the modern automatics (fig . 33) lies in the mechanism by which the cycle of operations is rendered absolutely See also:

• INDEPENDENT

independent of attendance, beyond the first adjustments and the insertion of a fresh bar as often as the previous one becomes used up . The movements of the rotating turret and of the cross-slide, and the feeding of the bar through the hollow spindle, take place within a second, at the conclusion of the operation preceding . These movements are effected by a set of mechanism independent of that by which the headstock spindle is rotated, viz. by cams or See also:

• CAM (CAO), DIOGO (fl. 1480-1486)

cam drums on a horizontal cam shaft, or other See also:

• EQUIVALENT

equivalent device, differing much in arrangement, but not principle . Movements are hastened or retarded, or pauses of some moments may ensue, according to the cam arrangements devised, which of course have to be varied for pieces of different proportions and dimensions .

But when the machines with their tools are once set up, they will run for days or See also:

• WEEKS, EDWIN LORD (1849-1903)

weeks, repeating precisely the same cycle of operations; they are self-lubricating, and only require to be fed with fresh lengths of bar and to have their tools resharpened occasionally . Of these automatics alone there are something like a dozen distinct types, some with their turrets vertical, others horizontal . Not only so but the use of a single spindle is not always deemed sufficiently economical, and some of these designs now have two, three and four separate work spindles grouped in one head . C A, Turret . B, Tool for first operation or chucking . C, Cutting tools for second operation, starting or pointing . D, See also:

• BOX
• BOX (Gr. irl or, Lat. buxus, box-wood; cf. 2r6Eir, a pyx)

Box tool carrying two cutters for third operation, rough turning . E, Similar tool for See also:

• FOURTH

fourth operation, finish turning . F, Screwing tools in head for final operation of screwing . Specialized Lathes.—Outside of these See also:

• MAIN (from the Aryan root which appears in " may " and " might," and Lat. magnus, great)
• MAIN (Lat. Moenus)

main types of lathes there are a large number which do not admit of group classification . They are designed for special duties, and only a representative See also:

• LIST (O.E. lisle, a Teutonic word, cf. Dut. lust, Ger. Leiste, adapted in Ital. lista and Fr. lisle)
• LIST, FRIEDRICH (1789-1846)

list can be given . Lathes for turning tapered work form a limited a, a, a, Cams for actuating chuck movements through pins b, b .

The cam which re-turns D is adjustable but is not in view . c, Feeding cam for turret . d,d,Return cams for turret . e, e,Cams on cam disk for operating the lever f, which actuates the cut-off and forming slide . T, Worm-wheel which drives cam shaft by a worm on the same shaft as the feed-pulley U . V, Handwheel on worm shaft for making first adjustments . W, Change feed disk . g, g,Change feed dogs adjustable round disk . X, Change feed lever . Y, Oil tube and spreader for lubricating tools and work . Z, Tray for tools, &c . number, and they include the usual provisions for ordinary turning .

In some designs change wheels are made use of for imparting a definite movement of cross traverse to the tool, which being compounded with the parallel sliding movements produces the See also:

• TAPER (probably of Celtic origin, cf. Irish tapar, Welsh tampr, taper, torch)

taper . In n others an upper bed carrying the heads and work swivels on a See also:

• LOWER

lower bed, which carries the slide rest . More often tapers are turned by a cross See also:

• ADJUSTMENT (from late Lat. ad juxtare, derived from juxta, near, but early confounded with a supposed derivation from justus, right)

adjustment of the loose poppet, or by a taper See also:

• ATTACHMENT

attachment at the rear of the lathe, which coerces the movement of the See also:

• TOP (cf. Dan. top, Ger. Topf, also meaning pot)

top or tool-carrying slide of the rest . Or, as in short tapers, the slide-rest is set to the required angle on its carriage . Balls are sometimes turned by a spherical attachment to the slide-rest of an ordinary lathe . Copying lathes are those in which an object is reproduced from a See also:

• PATTERN

pattern precisely like the objects required . The commonest example is that in which gun-See also:

• STOCKS

stocks and the spokes of wheels are turned, but these are used for See also:

• TIMBER

timber, and the engineer's copying lathe uses a form or cam and a milling cutter . The form milling machine is the copying machine for metal-work . The manufacture of boilers has given See also:

• BIRTH (a word common in various forms to Teutonic languages from the root of the verb " to bear ")

birth to two kinds of lathes, one for turning the See also:

• BOILER

boiler ends, the other the boiler flue flanges, the edges of which have to be caulked . Shaft pulleys have appropriated a special lathe containing provision for turning the convexity of the faces . Lathes are duplicated in two or three ways . Two, four, six or eight tools sometimes operate simultaneously on a piece of work .

Two lathes are mounted on one bed . A tool will be boring a hole while another is turning the edges of the same wheel . One will be boring, another turning a wheel tire, and so on . The rolls for See also:

• IRON [symbol Fe, atomic weight 55.85 (0=16)]

iron and See also:

• STEEL, FLORA ANNIE (1847– )

steel- mills have special lathes for trueing them up . The thin See also:

• SHEET

sheet metal-work produced by See also:

• SPINNING (from O. Eng. spinnen, to spin, cf. Ger. spinnen, &c., the Teut. root is seen, to draw out, cf. span, spider)

spinning has given rise to a special kind of spinning lathe where pressure, and not cutting, is the method adopted . Methods of Holding and Rotating Work . Chucks.—The term chuck signifies an appliance used in the lathe to hold and rotate work . As the dimensions and shapes of the latter vary extensively, so also do those of the chucks . Broadly, however, the latter correspond with the two principal classes of work done in the lathe, that between centres, and that held at one end only or face work . This of course is an extremely comprehensive classification, because chucks of the same name differ vastly when used in small and large lathes . The chucks, again, used in turret work, though they grip the work by one end only, differ entirely in design from the face chucks proper . Chucking between Centres: The simplest and by far the commonest method adopted is to See also:

• DRILL

drill countersunk centres at the ends of the work to be turned, in the centre or See also:

• LONGITUDINAL

longitudinal axis (fig .

34, A), and support these on the point centres of headstock and poppet . The angle included by the centres is usually 6o°, and the points may enter the work to depths ranging from as little as in. in very 116 light pieces to i in., a in. or I in. in the heaviest . Obviously a piece centred thus cannot be rotated by the See also:

• MERE
• MERE, ADALBERT (1838-1909)

mere revolution of the lathe, but it has to be driven by some other See also:

• AGENT (from Lat. agere, to act)

agent making See also:

• CON

con- D FIG . 34 . A, Centring and driving ;a, point B, Face-plate See also:

• DRIVER, SAMUEL ROLLES (1846– )

driver or catch-centre; b, See also:

• CARRIER
• CARRIER, JEAN BAPTISTE (1956-1794)

carrier; c, driver plate; a, centre; b, driver. fixed in slot in body of point C, Common See also:

• HEART
• HEART, LUNG

heart-shaped carrier. centre; d, back centre; e, D, See also:

• CLEMENT (Lat. Clemens, i.e. merciful; Gr. K)4gs)
• CLEMENT, FRANCOIS (1714-1793)
• CLEMENT, JACQUES (1567-1589)

Clement doubledriver ; a, f See also:

• ACE (derived through the Lat. as, from the Tarentine form of the Gr. etc)

ace- work. plate ; b, b, drivers ; c, loose plate carrying drivers . nexion between it and the mandrel . The wood turner uses a forked or prong centre to obtain the necessary leverage at the headstock end, but that would be useless in metal . A driver is therefore used, of which there are several forms (fig . 34), the essential See also:

• ELEMENT (Lat. elementum)

element being a short stiff prong of metal set away from the centre, and rotating the work directly, or against a carrier which encircles and pinches the work . As this method of driving sets up an unbalanced force, the " Clement " or See also:

• DOUBLE
• DOUBLE (from the Mid. Eng. duble, the form which gives the present pronunciation, through the Old Er. duble, from Lat. duplus, twice as much)

double driver (fig . 34, D), was invented, and is frequently made use of, though not nearly so much as the common single driver . In large and heavy work it is frequently the practice to drive in another way, by the dogs of the face-plate .

Steadies.—Pieces of work which are rigid enough to withstand the stress of cutting do not require any support except the centres . A, Travelling steady with adjust- slotted bolt holes a, a; b, b, able studs a, a; b, work; See also:

• BRASS
• BRASS (O. Eng. braes)

brass or steel facings . c, tool; d, slide-rest . C, Fixed steady with hinged top B, Steady with horizontal and and three setting pieces. vertical adjustment through But long and comparatively slender pieces have to be steadied at intermediate points (fig . 35) . Of devices for this purpose there are many designs; some are fixed or bolted to the bed and are shifted when necessary to new positions, and others are bolted to the carriage of the slide-rest and move along with it—travelling A, Main body . B, Waste oil tray . C, Headstock . • Wire-feed tube . • Slide for closing chuck . • Shaft for See also:

• DITTO (from the Lat. dictum, something said, Ital. detto, aforesaid)

ditto . • Feed-slide .

• Piece of work . • Turret with box tools . • Turret slide . • Sadule for ditto, adjustable along bed . Screw for locating adjustable slide . • Cut-off and forming cross-slide . • 0, Back and front tool-holders on slide . • Cam shaft . Cam See also:

• DRUM (early forms drome or dromme, a word common to many Teut. languages, cf. Dan. tromme, Ger. Trommel: the word is ultimately the same as " trumpet," and is probably onomatopoeic in origin; it appears late in Eng. about the middle of the 16th century)

drum chuck . • Cam drum turret . • Cam disk for actuating cross-slide . for operating for operating A, Plain mandrel .

B, Stepped mandrel . C, Expanding mandrel. adopted when wheels, pulleys, bushes and similar articles are bored first and turned afterwards, being chucked by the See also:

• BORE

bore hole, which fits on a mandrel . The latter is then driven between point centres and the bore fits the mandrel sufficiently tightly to resist the stress of turning . The large number of bores possible involves See also:

• STOCKING (a diminutive of " stock," post, stump, properly that which is stuck or fixed)

stocking a considerable number of mandrels of different diameters . As it is not usual to turn a mandrel as often as a piece of work requires chucking, See also:

• ECONOMY

economy is studied by the use of stepped mandrels, which comprise several diameters, say from three to a dozen . A better device is the expanding mandrel, of which there are several forms . The essential principle in all is the capacity for slight adjustments in diameter, amounting to from ; in, to 1 in., by the utilization of a long taper . A split, springy See also:

• CYLINDER (Gr. KvAwSpos, from KvXivaety, to roll)

cylinder may be moved endwise over a tapered body, or separate single keys or See also:

• BLADES, WILLIAM (1824-1890)

blades may be similarly moved . Face-Work.—That kind of work in which support is given at the headstock end only, the centre of the movable poppet not being required, is known as face-work, It includes pieces the length of which ranges from something less than the diameter to about three or four times the diameter, the essential See also:

• CONDITION (Lat. condicio, from condicere, to agree upon, arrange; not connected with conditio, from condere, conditum, to put together)

condition being that the unsupported end shall be sufficiently steady to resist the stress of cutting . Work which has to be bored, even though long, cannot be steadied on the back centre, and if long is often supported on a cone plate . The typical appliance used for face-work is the common face-plate (fig . 37) .

It is a plain disk, screwed on the mandrel A, Screwed hole to See also:

• FIT

fit mandrel See also:

• NOSE (O.Eng. nosu, cf. Dutch neus, Swed. nos, snout; the Aix in Provence. Both at Aix and at Lyons he acquired great connexion with O.Eng. nasu is obscure, cf. Ger. Nase, Lat. pares, distinction by his labours during outbreaks of the plague. In nostrils,

nose . B, Slots for common bolts . C, Tee-slots for tee-head bolts . nose, and having slot holes in which bolts are inserted for the purpose of cramping pieces of work to its face . There are numerous forms of these clamps, and common bolts also are used . The face-plate may also serve to receive an intermediary, the angle-plate, against which work may be bolted when its shape is such as to render bolting directly to the plate inconvenient . See also:

• JAW (Mid. Eng. jawe, jowe and geowe, O. Eng. cheowan, connected with " chaw " and " chew," and in form with " jowl ")

Jaw Chucks.—When a face-plate has fitted to it permanent dogs or jaws it is termed a See also:

• DOG

dog or jaw chuck (fig . 38) . In the commonest form the jaws are moved radially and independently, each by its own screw, to grip work either externally or internally . In some cases the dogs are loosely fitted to the holes in a plain face-plate . In all these types the radial setting is tentative, that is, steadies . In some the work is steadied in a vee, or a right angle, in others adjustable pins or arms are brought into contact with it .

As the pressure of the cut would cause an upward as well as back-ward yielding of the work, these two movements are invariably provided against, no See also:

• MATTER

matter in what ways the details of the steadies are worked out . Before a steady can be used, a light cut has to be taken in the locality where the steady has to take its bearing, to render the work true in that place . The travelling steady follows immediately behind the tool, coming in contact therefore with finished work continually . Mandrels.—Some kinds of work are carried between centres indirectly, upon mandrels or arbors (fig . 36) . This is the method the jaws being independent, there is no self-centring capacity, and thus much time is lost . A large group, therefore, are rendered self-centring by the turning of a ring which actuates a face See also:

• SCROLL

scroll A, Body. b, Square heads of screws for a, Recess to receive face-plate . See also:

• KEY
• KEY (in O. Eng. tang; the ultimate origin of the word is unknown; it appears only in Old Frisian kei of other Teutonic languages; until the end of the 17th century the pronunciation was kay, as in other words in O. Eng. ending in aeg; cf. daeg, day; clang
• KEY (the phraseograms being indicated by hyphens)
• KEY, SIR ASTLEY COOPER (1821-1888)
• KEY, THOMAS HEWITT (1799-1875)

key, B, Jaws or dogs. c, Tee-grooves for bolts . C, Screws for operating jaws . A a a - ----- -------- C A, Face-plate screwed to man- E, Jaws in chuck face, having drel nose. sectional scroll teeth en- B, Back of chuck screwed to gaging with scroll a, and A. moved inwards or outwards C, Knurled chuck body with by the scroll when C is scroll a on face. turned . D, Chuck face. b, Tommy or lever hole in C . F, Piece of work outlined .

Scroll Chuck . A, Back plate; a, recess for face-plate . B, Pinions . C, Circular rack with scroll b on face . D, Chuck body . E, Jaws fitting on intermediate pieces c that engage with the scroll b . d, Screws for operating jaws independently . A, Back . B, Body . C, See also:

• SPIRAL

Spiral plate with teeth engaging in jaws D . E, Bevel pinions gearing with teeth on back of C . (fig .

39) or a circular rack with pinions (fig . 40), turned with a key which operates all the jaws simultaneously inwards or outwards . But as some classes of jobs have to be adjusted eccentrically, many chucks are of the See also:

• COMBINATION (Lat. combinare, to combine)

combination type (fig . 40), capable of being used independently or con-centrically, hence termed universal chucks . The change from one to the other simply means throwing the ring of teeth out of or into engagement with the pinions by means of cams or equivalent devices . Each type of chuck occurs in a large range of dimensions to suit lathes of all centres, besides which every lathe includes several chucks, large and small, in its equipment . The range of diameters which can be taken by any one chuck is limited, though the jaws are made with steps, in addition to the range afforded by the operating screws . The " See also:

• TAYLOR
• TAYLOR, ANN (1782-1866)
• TAYLOR, BAYARD (1825–1878)
• TAYLOR, BROOK (1685–1731)
• TAYLOR, ISAAC (1787-1865)
• TAYLOR, ISAAC (1829-1901)
• TAYLOR, JEREMY (1613-1667)
• TAYLOR, JOHN (158o-1653)
• TAYLOR, JOHN (1704-1766)
• TAYLOR, JOSEPH (c. 1586-c. 1653)
• TAYLOR, MICHAEL ANGELO (1757–1834)
• TAYLOR, NATHANIEL WILLIAM (1786-1858)
• TAYLOR, PHILIP MEADOWS (1808–1876)
• TAYLOR, ROWLAND (d. 1555)
• TAYLOR, SIR HENRY (1800-1886)
• TAYLOR, THOMAS (1758-1835)
• TAYLOR, TOM (1817-1880)
• TAYLOR, WILLIAM (1765-1836)
• TAYLOR, ZACHARY (1784-1850)

Taylor " spiral chucks (fig . 41) differ essentially from the scroll types in having the actuating threads set spirally on the sloping interior of a cone . The result is that the outward pressure of each jaw is received behind the body, because the spiral rises up at the back . In the ordinary scroll chucks the pressure is taken only at the bottom of each jaw, and the tendency to tilt and pull the teeth out of shape is very noticeable . The spiral, moreover, enables a stronger form of tooth to be used, together with a finer pitch of threads, so that the wearing See also:

• AREA

area can be C1 increased .

The foregoing may be termed the standard chucks . But in addition there are large numbers for dealing with special classes of work . Brass finishers have several . Most of the hollow spindle lathes and automatics have draw-in or push-out chucks, in which the jaws are operated simultaneously by the conical bore of the encircling nose, so that their action is instantaneous and self-centring . They are either operated by hand, as in fig . 31, or automatically, as in fig . 33 . There is also a large group used for drills and reamers—the drill chucks employed in lathes as well as in drilling machines . II.—RECIPROCATING MACHINE TOOLS This is the only convenient head under which to group three great classes of machine tools which possess the feature of reciprocation in common . It Includes the planing, shaping and slotting machines . The feature of reciprocation is that the cutting tool is operative only in one direction; that is, it cuts during one stroke or movement and is idle during the return stroke . It is, therefore, in precisely the same condition as a hand tool such as a See also:

• CHISEL (from the O. Fr. cisel, modern ciseau, Late Lat. cisellum, a cutting tool, from caedere, to cut)

chisel, a See also:

• CARPENTER, LANT (1780-1840)
• CARPENTER, MIRY (1807-1877)
• CARPENTER, WILLIAM BENJAMIN (1813-1885)

carpenter's See also:

• PLANE

plane or a hand saw .

We shall return again to this feature of an idle stroke and discuss the devices that exist to avoid it . Planing Machines.—In the standard planer for general See also:

• SHOP

shop purposes (fig . 42) the piece of work to be operated on is attached to a horizontal V table moving to and fro on a rigid bed, and passing underneath the fixed cutting tool . The tool is gripped in a box having certain necessary adjustments and movements, so that the tool can be carried or fed transversely across the work, or at right angles with the direction of its travel, to take successive cuts, and also downwards or in a vertical direction . The tool-box is carried on a cross-slide which has capacity for several feet of vertical adjustment on up-right members to suit work of varying depths . These up-rights or housings are bolted to the sides of the bed, and the whole framing is so rigidly designed that no perceptible tremor or yielding takes place under the heaviest duty imposed by the stress of cutting . a 44 S -a 44 b 44 GO -~ R ! U N a a 3 w nv 0 N o a • ss 'le SID ''5 n op x E- in a N _- ':N cv oa 3 u . X .0 v 64Coal / ro N o ° o P . ~ . [° txO w 0.4 Zs, > b.O C3r °= chi', > buo 44 ae u cub 3s . ° ao v a d 008 .

Zm 7 +See also:

• DAM

dam d • N m o o to [ v • w P.P. a i .--• ; . ~No Moreover, after the required adjustments have been made and the machine started, the travel and the return of the work-table and the feeding of the tool across the See also:

• SURFACE

surface are performed by self-acting mechanism actuated by the reciprocations of the table itself, the table being driven from the See also:

• BELT (a word common to Teutonic languages, the Old Ger. form being bale, from which the Lat. balteus probably derived)
• BELT, THOMAS (1832-1878)

belt pulleys . To such a design there are objections, which, though their importance has often been exaggerated, are yet real . First, the cross-rail and housings make a rigid enclosure over the table, which sometimes prevents the See also:

• ADMISSION

admission of a piece that is too large to pass under the cross-rail or between the housings . Out of this A, Bed . G, Tool-box on travelling See also:

• ARM (a common Teutonic word; the Indo-European root is ar, to join or fit; cf. the Lat. armus, shoulder, and the plural word arma, weapons, Gr. apphs, joint, and the reduplicated apapilKSV, to join)

arm H, travelled by fast and loose B, B, Feet. pulleys J for cutting, and by pulleys K for See also:

• QUICK

quick return . C, C, Work tables adjustable vertically on the faces D, D, by L, Feed-See also:

• ROD (O.E. rodd, probably related to Norw. rudda, stick, rodda, stake)
• ROD, EDOUARD (1857-1910)

rod with adjustable dogs a, a, for effecting reversals through means of screws E, E, from handles F, F, through bevel the belt forks b, b . gears . M . See also:

• BRICKWORK

Brickwork See also:

• PIT (O. E. pytt, cognate with Du. put, Ger. Pfutze, &c., all ultimately adaptations of Lat. puteus, well, formed from root pu-, to cleanse, whence gurus, clean, pure)

pit to receive deep objects . (G . See also:

• RICHARDS, ALFRED BATE (182o-1876)
• RICHARDS, HENRY BRINLEY (1819-1865)
• RICHARDS, WILLIAM TROST (1833-1905)

Richards & Co., Ltd., See also:

• MANCHESTER
• MANCHESTER (popularly Manchester-by-the-Sea)
• MANCHESTER, EARLS AND DUKES OF

Manchester.) FIG .

43.—20-in . See also:

• SIDE
• SIDE (mod. Eski Adalia)

Side Planing Machine . c B A, See also:

• BASE

Base . B, Work-table, having vertical movement on carriage C, which has horizontal movement along the face of A . D, Screw for effecting vertical movement, by handle E, and bevel gears . F, Screw for operating longitudinal movement with feed by hand or See also:

• POWER [WILLIAM GRATTAN] TYRONE (1797-1841)

power . G, Tool See also:

• RAM
• RAM, PIERRE FRANCOIS XAVIER DE (18o4-1865)

ram . H, Tool-box . a, Worm-gear for setting tool-holder at an angft . b, See also:

• CRANK

Crank handle spindle for operating ditto . c, Handle for actuating down feed of tool . J, Driving cone pulley actuating pinion d, disk wheel e, with slotted disk, and adjustable nut moving in the slot of the crank f, which actuates the lever g, connected to the tool ram G, the See also:

• MOTION (Lat. motio, from movere, to move)
• MOTION, LAWS OF

motion constituting the See also:

• WHITWORTH
• WHITWORTH, SIR JOSEPH

Whitworth quick return; g is pivoted to a See also:

• BLOCK
• BLOCK (from the Fr. bloc, and possibly connected with an Old Ger. Block, obstruction, cf. " baulk ")
• BLOCK, MAURICE (1816–19or)

block which is adjustable along a slot in G, and the clamping of this block in the slot regulates the position of the ram G, to suit the position of the work on the table .

k, Feed disk driven by small gears from cone pulley . j, Pawl driven from disk through levers at various rates, and con-trolling the amount of rotation of the feed screw F . K, Conical mandrel for circular shaping, driven by worm and wheel 1 . objection has arisen a new design, the side planer (fig . 43), in which the tool-box is carried by an arm movable along a fixed bed or base, and overhanging the work, which is fastened to the side of the base, or on angle brackets, or in a deep pit alongside . Here the important difference is that the work is not traversed under the tool as in the ordinary planer, but the tool moves over the work . But an evil results, due to the overhang of the tool arm, which being a See also:

• CANTILEVER (a word of doubtful origin, probably derived from " lever," in its ordinary meaning, and " cant," an angle or edge, or else from modern Lat. quanta libra, of what weight)

cantilever supported at one end only is not so rigid when cutting as the cross-rail of the ordinary machine, supported at both ends on housings . The same idea is embodied in machines built in other respects on the reciprocating table See also:

• MODEL (0. Fr. modelle, mod. modele; It. modello, pattern, mould; from Lat. modus, measure, standard)

model . Sometimes one See also:

• HOUSING

housing is omitted, and the tool arm is carried on the other, being therefore unsupported at one end . Sometimes a housing is made to be removable at See also:

• PLEASURE (through Fr. plaisir from Lat. placere, to please; Gr. rlbovii)

pleasure, to be temporarily taken away only when a piece of work of unusual dimensions has to be fixed on the table . Another objection to the common planer is this . It seems unmechanical in this machine to reciprocate a heavy table and piece of work which often weighs several tons, and let the tool and its holder of a few hundredweights only remain stationary .

The mere reversal of the table absorbs much greater See also:

• HORSE (a word common to Teutonic languages in such forms as hors, hros, ros; cf. the Ger. ross)

horse-powerthere is no See also:

• LIMITATION, STATUTES OF

limitation whatever to the length of the work, since it may extend to any distance beyond the base-plate . Shaping Machines.—The shaping machine (fig . 44) does for comparatively small pieces that which the planer does for long ones . It came later in time than the planer, being one of See also:

• JAMES
• JAMES (Gr. 'IlrKw,l3or, the Heb. Ya`akob or Jacob)
• JAMES (JAMES FRANCIS EDWARD STUART) (1688-1766)
• JAMES, 2ND EARL OF DOUGLAS AND MAR(c. 1358–1388)
• JAMES, DAVID (1839-1893)
• JAMES, EPISTLE OF
• JAMES, GEORGE PAYNE RAINSFOP
• JAMES, HENRY (1843— )
• JAMES, JOHN ANGELL (1785-1859)
• JAMES, THOMAS (c. 1573–1629)
• JAMES, WILLIAM (1842–1910)
• JAMES, WILLIAM (d. 1827)

James See also:

• NASMYTH, ALEXANDER (1758-1840)
• NASMYTH, JAMES (1808-1890)

Nasmyth's inventions, and beyond the fact that it has a reciprocating non-cutting return stroke it bears no resemblance to the older machine . Its design is briefly as follows: The piece of work to be shaped is attached to the top, or one of the vertical side faces, of a right-angled See also:

• BRACKET

bracket or brackets . These are carried upon the face of a main standard and are adjustable thereon in horizontal and vertical directions . In small machines the ram or reciprocating arm (see fig . 44, G) slides in fixed guides on the top of the See also:

• PILLAR (0. Fr. piler, Mod. pilier, Late Lat. pilare, from pila, column)

pillar, and the necessary side traverse is imparted to the work table B . To the top of the main standard, in one design, a carriage is fitted wifh horizontal traverse to See also:

• COVER (from the Fr. convert, from couvrir, to cover, Lat. cooperire)

cover the whole breadth, within the capacity of the machine, of any work to be operated on . In the largest machines two See also:

• STANDARDS

standards support a long bed, on which the carriage, with its ram, traverses past the work . These machines are frequently made double-headed, that is carriages, rams and work tables are dupli- A, Main framing . B, Driving cone .

C, D, Gears driven by cones . E, Shaft of L . F, Tool ram driven from shaft E through disk G and rod H, with quick return mechanism D . J, See also:

• COUNTER

Counter-See also:

• BALANCE (derived through the Fr. from the Late Lat. bilantia, an apparatus for weighing, from bi, two, and lanx, a dish or scale)