A Treatise on Lathes and Turning Simple Mechanical and Ornamental 1000177405

8/12/2019 A Treatise on Lathes and Turning Simple Mechanical and Ornamental 1000177405

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r.'.y .

A TREATISE

ON

LATHES AND TURNING

SIMPLE, MECHANICAL, AND ORNAMENTAL

BY

W. HENEY NOETHCOTTAiriBOB or A TBBATlaX OK 'THB THaOBY AMD ACTIOH OF THB SIUII XXOINS'

SECOND EDITION

WITB THRBS BUHDRED ASD TBIBTT-KIOBT ILLVaTRATIOSS

LONDONLONGMANS, GEEEN, AND CO.

1876

Alt right* teierved


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TO

^

EDWABD CAFFIN, ESQ.

MASTER OF THE WORSHIPFUL COMPANY OF TURNERS.

Mt BEAR Sib,

As a member of your Ancient and Honourable G-uild,

I beg to dedicate to you, its Worshipful Master, this second

edition of my treatise on ' Lathes and Turning.'

The useful measures of technical advancement inau-urated

by the Turners Company, and so warmly promoted

by yourself, tend greatly to encourage artistic skill and

honourable emulation amongst craftsmen ; and I trust that

my attempt to expose the mysteries and secrets of the craft

will not be considered treasonable.

I am, dear Sir,

Your obedient servant,

HENRY NORTHCOTT.


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PEEFACE.

The present volume is intended as a * Handbook ' for theuse of students in mechanics, amateur turners, and otherswho are interested in the art of turning. Proficiencyin this most useful art is not to be acquired from booksalone, but I beUeve the information given in the follow-ng

pages may be taken as sound and practical, whilstthe lathes, tools, and appliances described are those ofthe present day.

The first part is devoted mainly to the descriptionof the principal varieties of lathe in use. The secondpart treats of turning with hand tools in hard andsoft woods, ivory, c., also, in iron and the metalsgenerally; this part includes screw chasing, drilhng,fret sawing, and other subsidiary operations. Thethird part describes the self-acting lathe and its uses,including screw cutting, boring, turning irregular shapes,wheel cutting, milling, slot drilling, planing, c. Thefourth part is on ornamental turning, with a descrip-ion

of the ornamental lathe, the ellipse,the eccentric, thegeometric, the compound geometric and other chucks ;the eccentric, ellipse, rose and other ornamentinginstruments, the spherical slide rest, c., c. Thewhole being illustrated by three hundred and thirty-


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VUl FREFAGB.

eight engravings of lathe apparatus and eiuimples ofturned work, of which ninety-nine are new to thisedition.

Messrs. Sir Joseph Whitworth and Co., Messrs.Fairbairn, Kennedy, and Naylor and other eminentmakers were good enough to furnish me with thephotographs from which the illustrations of latheswere engraved. To Mr. Henry Perigal, F.E.A.S.,c., c., I am indebted for much valuable informationand aid in connection with the special subject ofgeometric turning. And last, but not least, Mr. JamesKasmytb has kindly contributed a chapter on ' Hard-ning

and tempering steel tools.'I may add that I hope shortly to publish a sequel

to this work in the form of a volume devoted ex-

dudvely to * Examples of Plain and OrnamentalTurning.'

W. H. NOBTHCOTT.

SomfZEnc Clvb, Lokimk^ 1876.


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CONTENTS.

PAOB

Wbat 18 the lathe 1Definition of turning 1Invention of the lathe 2Course of improvement in the lathe ^8Hand lathes 5Double gearing 6Slide-rests

7

Modesof making slide* rest automatic 8Self-acting lathes 9Sur cing do 10Screw-cutting do 11On leading screws 12Duplex lathee 14Ornamental do 14Special do 15Driving by treadles 16

,,8t and looee pulleys 18

Modes of reversing 19Home-made lathes 21On the choice of a lathe 22

'Points' of a good lathe 23Technical terms 25On hand-tool turning 28Driving chucks

.SO

Universal mandrils 34Temporary chucks 3dSpring do 37Mode of using the chucks 38Tools for soft wood turning 40Tools for hard woods 42On grinding tools 44Cutting position of tools 45


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X CX)NTENTS.

PAOK

Placingthe tool-rest . . 46Callipers 47Woods used for turning 48Chittingspeedsfor woods and ivory . . 50Turning a cylinderin soft wood ..... 52Mode of holdingthe tools . . . 54Polishingsoft woods 57Turning in hard woods ........ 58Polishing do 59Turning a box 60

sphere 62l vHJttS ,. .. ,. , ,. . . OO

Chinese balls . 64,^ spikedarticles 65

Hand-turping in metals . 67Qualities of iron ......... 68Annealing steel . . . ... . ,69Turning cast ircm ......... 70

brass and gun metal 71Cutting anglesof tools for metal . 72Centres and carriers

. . 73Driving chucks ......... 74Mandrils

......... 75Hook tools 76Mode of holding do .77Metal-turningtools 79

jj chisels . . . . '. .80Tools for cast iron 82Tools for brass and cast iron 83Cutting speedsfor metals . 85Polishing cast and wrought iron ..... 86How to turn wrought iron . . . . . . 88Knocking work on and off mandrils . , . .91Screw chasing 93Drillingand baring 96Drills,c 97Mode of using drills 98Rhymers 101Pin drilling 102Boring bits 104Chucking work for boring ....... 106The boring rest 108The D- bit 110


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rCONTENTS.. XI

PAOB

Lapping and grindingholes 112Hand drills . . .118Cironlar sawing 114Fret do 115Making millingtools . . . 116

chasing do 117Buffingand polishing 117The self-actingathe 118Slide rest of do 123Self-actingaming 128Chucks and drivinginstraments 181Slide-Test tools for metals 188Guttingspeedsfor self-actingurning 186Lubricatingthe cuttingtools . 187Speedsof trayerse 188General instruction for turning 189Turning a longshaft 142TheLstaj 148Springtools . . . . ... . . 146Using the standard plugs . . . 148Conical turning 149What is a screw 151Earlymodes of cutdng screws 152Whitworth standard threads 153Shape of screw threads 154Change wheels 156Calculatingwheels 157Screwingtools for woods 159Landingplaces ,, 161Instructions for screw cutting 162Self-actingrilling . . . . 164Turning irregularshapes . 167Wheel cutting 177Bevel do ....:.... 184Spiralwheel cutting 185Hack cutting 186Circular cutters 186Instrument for making cutters 189Flutingand slot drilling 193Planingand slotting 197Repairingtools 201Tool forge 205Hardeningand temperingsteel tools 205


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231 CONTENTS.

PAOBThe ornamental lathe 210Trayening mandril 218Ornamental aiide-rest 215Overhead apparatus 217Ornamental turning 218Tools for do

. .220

Screw traversing 224Ornamental engraving 229Slide-rest applied to engraving 288The eccentric chuck and its uses 287The eccentric cutting instrument

. . . .241

The ellipse chuck 245The ellipsecutting instrument

......250

The rose do do 258Straight line chucks

. .262

Bo8e engine lathes 268Combination of ornamental apparatus , . . . . 264Double counting 266The compensating index 278The geometric chuck

276

Geometric turning. .

280The compound geometric chuck 298Ornamental cutting and carving 808The curvilinear apparatus 806The spherical slide-rest 807Turning skew or oblique work

......809

Ornamental drills. . . : . . . .

810Universal cutting instrument 810The spherical chuck 811The spiral chuck 811The spiral apparatus 812Drilled work 818Spiral do

.814

Examples of drilled and other work 814Sharpening tools 315


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I

ILLUSTBATIONS.- ^

LATHES AND TURNING.nouBs

Simplehand lathe 1n with aUde-rest 2

Compound slide-rest 8Self-actdngnd sor cmg elidelathe,0-in. centres . . . 4Slide break lathe,21-m. oentree 5Duplex screw-cattingathe,lO-in. centres . . . 6Duplex self-actingathe with break 7Screw-cuttingathe for foot power, 5-in. centres . . 8Railwayaxle lathe , . 9Railwaywheel lathe 10Double lathe for bolts and studs 11

HAND-TOOL TURNING IN WOODS, c.DriU-chuck 12Prong driver 18Cross do 14Taper screw chuck 15Five pin or platechuck 16Cone chuck 17Uniyersal mandril 18Male and female screw chucks 19 20Chuck-plate 21Pin-wrench 22Tools for taming soft woods 28 80

^hard woods and ivory . 31 50Position of gouge and soft wood chisel in use . . 51

soft wood scrapinghisel do . .52 hard wood do do 58


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XIV ILLUSTRATIONS.

nauiuB

Hand-tool rest or tee 54Outside callipers 55Inside do 56Indicating do 57Handle for tunung tools 58Vase stem (example of turning) 59Mode of using cross kerf driver . . . . . .60Snufl^-box (example of turning) .... 61 62Vase (example of turning) . 63Object with six spikes (example of tuminff) . . . . 64Cube with intermd spikes(ipleof turSng)... 65Polygon with internal spikes(example of turning) . . 66Vases, c. (examples of turning) 67

HAND TOOL TURNING IN METALS.'

Lathe centres for lightand heavy work . . . 68 69Female do 70Carriers or drivers for round iron,flat iron and screws 71 73Centre punch and cone centre punch . . . 74 75Driving chuck . . . , 76Die do 77Round mandrils and screw mandrils .... 78 80Hook tool for hand-turning 81Tool- rest for metal turning 82Position of hook tool when in use . . \ . . 83Hand- tools for metal turning . . . 84 90Handle for do 91Position of metal-turningchiiselsin use . . . .92Polishingtools for metals . 93Position of tools in use .94Scraping tools for brass and cast iron . 95 104Position of tools in use 105Glazing clamps and emery sticks .... 106 107Position and angle of chisel for turningbrass .... 108

SCREW CHASING BY HAND.Male chasing tools 109Female do

.110


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ILLUSTRATIONS. XV

DRILLING AND BORING.

Drilla . . . 111 116Pin drills,ounter-sinkB,rhymers . . . . 116 120American drill and chuck . 121Faceplate 122Cup or 8-8crew chuck 123Boring tools 124 126Boring rest . . 127Die stay or steadybearing 128Boring wrench * ., . . ... . . 129Lead grinderor lap . , . . ISOFaceplateclamps 131Hand-drillinginstrument .

,. . .

132

MISCELLANEOUS OPERATIONS.Circular sawing machine . . ' 138Fret-cuttingaw . . . . . 134Specimens of fret-sawing . . . . . . 135 136

SELF-ACTING LATHES AND THEIR USES.

End eluration of slide-rest 137Front elevation of universal lathe 138End elevation of do (left) 139End elevation of do (right) 140Square centre . . .' . . . . . 141Long do 142Standard plug and ringgauges 143Four-jaw chuck 144Self-centeringhuck 145Slide-rest tools 146 157Varieties of screw-threads 158Screw-cuttingtools for wood 159 160Screw-tool with shiftinglade 161Boring-barand centres 162Wheel-cuttingapparatus 163Circular cutter for wheel cutting 164Spindlefor flycutters 165Circular cutter for grooving 166


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XVI ILLUSTRATIONS.

Apparatus for making circular cutters . 167 168Drillingnstrument 169Drills for do 170 171Planinghead 172Slottingool 178Forge 174

ORNAMENTAL LATHES AND THEIR USES.Ornamental lathe 175Slide-rest tools for woods and irory,c 176 186Eccentric chuck 187

,, patterns 188 189Eccentric euttingnstrument .... 190Ellipsehuck 191

,y pattern 192Ellipseuttingnstrument 198

patterns 194 196Rose-cuttingnstrument 197

,, patterns 198Combination patterns 199 ^217Greometric chuck (simple) 218Patterns made by do 219 806Compound geometrichuck 807Figuresmade by do 808 828Sphericalliderest 824Examplesof obliquework 825 326Drills for ornamental work 827 880Cuttinginstrument ..... 881Sphericalhuck 882Spiralhudc SSSEgg-shellase . . ^ 884Drilled picturerame . * 885Hollow spiralork 886 887Drilled work (examples) 888


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LATHES AND TUBNING.

; PAET

DEFINITION OP TURNING.

The lathe is essentially an instrument by which sub-tancesare rotated upon an axis under such arrange-ents

that they may be cut and smoothed, or * turned 'by suitable tools. Turning is then the act or operationof shaping bodies by means of the lathe.

In its simplest form a lathe consists of two fixedpoints or centres, between which the object to beturned is rotated, and a chisel or other cutting tool isso held that all the portions of the material projectingbeyond the plane in which the point of the tool ismoved are cut away as the object rotates, leaving asmooth cylindrical surface. Lathes however are nowmade of very complex configuration, and many opera-ions

besides that of simple turning are performed bytheir instrumentality. In some cases, instead of thetool being stationary, and the object rotated, turning isperformed upon a stationary object by a revolving tool.In other cases, although the work is rotated and thecutting point is stationary, the operation is not termedturning, but ' drilling' or * boring/ according to the

B


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2 LATHES AND TURNING.

nature of the cuttingool employed. Generally,hena cylindricalody is producedby continuous rotation,it is said to be turned whether the cuttingtool or thework is rotated. If a circular hole ismade in a rotatingobject,the operationis termed turning only when aturningtool is employedto remove the surplusmaterial.If the hole is made by a revolvingool it is not usuallysaid to be turned, althoughthe operationmay havebeen performedin the lathe.The earliest form of lathe is no doubt of prehistoricinvention. It can at no time have been much moreelementarythan the rude instrument used from timeimmemorial in Eastern countries. This lathe is gene-ally

formed of two short wooden stakes or pegs driveninto the ground at a suitable distance apart, eachcarrying short pointedpieceof wire or even wood,to act as centres or supports for the objectto be turned.The work is rotated by means of a bow, somethinglikea fiddler's bow, the stringf which is twisted once ortwice round the work to giveitthe necessary hold. Inthe East the turner squats upon the ground and holdsthe chisel with one hand, whilst with the other hemoves the bow backwards and forwards so as to causethe work to rotate firstin one direction and then in theother. The chisel is guidedand steadied by the work-an's

great toe.Lathes of this kind are still employed in India,

China, and other Eastern countries,and apparentlyoattempt has been made by native workmen to improveupon them. Notwithstandinghe rudeness of the lathehowever, it must be admitted that Eastern turners areable to produce some very fine specimensof turnedwork.


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were concurrentlyffected in the generalconstructionand workmanship of the lathe,the mode of fixingthelathe centres, the use of a movable poppet, the ar-angement

of the tool rest,c., and the lathe wouldnow become a reallyuseful and eflSdent machine.

As the use of machinery extended so the value ofthe lathe became more apparent, and its applicationsmore numerous. It is adapted to the production oflargerand heavier work by the addition to the lathehead of double gearing for reducingthe speed and in-reasing

the power. The uncertain hand of the turnerwould find a substitute in the slide rest a mechanicalhand at once stronger and more exact than the humanhand. Some simple means are devised for moving thehandle of the slide rest from the lathe itself,nd thetool then becomes self-acting.y a mere extension ofthe slide rest principle,he lathe bed is itself formedinto a sUde for the tool carrier,and with a leadingscrew or other tool-movingmechanism we have thatmost useful of all machines ^the Self Acting SlideLathe.

Specialadaptationsof the lathe to the purposes ofcertain trades or certain work have been, and are,continuallymade. Many of these lathes with Iheiradjuncts possess great interest,and have been workedout with great ingenuity. For the purposes of thepresent work however, the lathes described and chieflyalluded to will be hand lathes,or simplelathes intendedfor the productionof moderatelylightturningin metalsand wood with hand tools ; the self-actinglathes,usedby the mechanical engineerin the productionof steamengines and other machinery; and the ornamental


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VARIETIES OP LATHE. 5

lathes,employed in the execution of light fancy orornamental turnery, chieflyin ivory and wood. A fewspecial lathes are described in connection with the self-actinglathe.

The hand lathe, at no very distant date the onlyone in use, is now chieflyused by wood tamers andamateurs. One of these is shown at Fig.1 ; a is thebed; b the cone-poppet or headstock; c the screw-poppet ; d the tool-rest ; e the treadle. These lathes canbe bought anywhere, and at pricesvarying from 21. to20^. Their capabilitiesre rather limited, but they arewell adapted * to teach the young idea how to turn.'

A better constructed lathe, of similar properties,asmade by Messrs. Easterbrook and AUcard, is shown atFig. 2. In this lathe a isthe bed, which is of metal;/ is the cone, or fast head-stock, also of metal, with asteel mandril and gun-metal bearings; c is themoving or screw head-stock, with a hand-wheeland tightening lever ; dis the tool-rest and holder;e the treadle for the feet;/ is the chain connectingthe treadle to the crank A ; j(^ is the gut band passingJover the driving pulley ion the crank-shaft, andcommunicating motion to the cone of the lathe-spindle;k, k are handles for listening the head-stock


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6 LATHES AMD TUEKING.

and rest-holder firmly on to the bed in a convenientposition;6, J are the two standards or supports for thelathe-bed; mis the back-board, or shelf, for placingtools and instruments upon within reach of the work-an's

hand.In these lathes, whether driven by the toot or by

eteam, it ia impossibleto produce work requiringmudiforce. Although ample power may be available,thestrap is insufficient to transmit it to the lathe-spindle,and the capabilityof varying the speed is but small,and unsuitable for any but smaU variations in the dia-eter

of the work. Lathes are therefore fitted withdouble or back gearing,which enables them to be usedupon

much heavier work, and of course renders thelathe much more serviceable. This double gear ac-omplishes

its object by diminishing the speed and


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THE SLIDE BESrr. 7

iQcreafdng the power in a corresponding proportion.It isvariouslyarranged,but usuallyit is set at the backof the lathe-spindle,s shown in several of the lathesillustrated. The neatest arrangement is that in whichthe wheels are enclosed in the cone-pulley;but thisis not so powerfiil,or is it so accessible as outsidegearing.

The capabilitiesf these lathes can be stillfurtherincreased by the addition of a aUde-rest, but then theycan scarcely be considered 'hand-lathes,' as that termis used to denote those lathes with which the work isperformed by hand-tools, or tools held in the hand.

The slide-rest,Fig. 3, is a sort of mechanical hand,

or instrument to be used instead of the hand, for hold-ngthe tools and applying them to the work. The

example given in the figureis of plain but convenientconstruction. The part a bolts down upon the bedwith the projectingpiecebetween the bars of the bed; is a handle, by moving which the sUde c is caused tomove upon a ; ^ is well fitted upon c, and is movedaround a central pin, and adjusted at any required


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10 LATHES AND TDKNING.

The rest, and consequently the tool, will then tra-erseor slide along the bed without further manual

assistance.A lathe of this sort is shown at Fig. 4, which is

taken from the lathes made by Messrs. Fairbaim,Kennedy, and Naylor, of Leeds. The cone-spindlecarries a supplementary con^puUey, for giving motionto the self-actingechanism. This lathe is automaticon both the longitudinalnd transverse motions thatis to say, the motion of the slide-rest along the bed isautomatic, as also is the motion of the tool along theslide of the slide-rest.

These lathes are seldom made smaller than with tenor twelve-inch centres, and the bed is usually madevery long ; but as in some cases the whole length ofbed is not required,it is customary to utilise the un-mployed

length by placing one or more headstocksupon the bed. These are removed when very longshafts have to be turned.

Self-actingurfiudng-lathesre for turningup largeplane sur ces, and are generallymade very massiveand heavy. The beds of these lathes are seldom madeof any great length,but their centres are raised veryhigh,so as to admit articles of large diameter. Theslide-rest is not required to travel any great distancealong the bed parallelto the line of centres, its chiefmotion being requiredparallelto the face-platecrossthe bed, at rightanglesto the line of centres. In largesurfacing-latheshere is some little difficultyn gettingthe proper variation of speed. The best are constructedso that the number of revolutions diminish as the tool


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VABIETI S OP LATHE. 11

travels from the centre, so as to keep the cuttingspeedconstant.

Many lathes are constructed for both siirfacingndtraversing.They have the beds of moderate length,and moderatelyhigh centres, and are adapted to turnarticles of small diameter and good length,surfaces ofmoderatelylargediameter, and also cylindersof mode-ate

size and length. Such a lathe is illustrated atFig.5, which is a Slide Break Lathe, 21-inch centres,made by Messrs. Fairbaim, Kennedy, and Naylor.These are used only by mechanics.

The lathe in greatest request is the self-actingcrew-cuttinglathe. This is able to perform all the work ofthose described,and, in addition,is capableof cuttingscrews of any incUnation or pitch. In some of thesethe rack and pinionfor traveramg are done away withaltogether,nd the saddle of the rest is caused to travelalongthe bed by means of a screw called a leadingcrew.When this is the case, the screw is used aUke for ordi-ary

sUding up or traversingnd for screw-cutting,hevariation in relative speed of traverse beinggainedbymeans of wheels termed * change wheels.' By changingthe wheels connecting the lathe-spindlend the lead-ng

screw, any required relative speed is obtainedbetween these two. Thus, for ordinary plain turningor traversing,he lathe-spindleould run very muchster than the leadingscrew. For cuttingfine screwsor screws of fine pitch,wheels woidd be put on whichwould cause the screw to run somewhat faster than fortraversing.To cut a moderately coarse thread, say,the same pitch as the leading screw itself,he lathe-


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12 LATHES AND TDBMNQ.

spindlewould be connected to the leadingscrew bysuch wheels as would cause the two to revolve at thesame speed,or at the same angularvelocity and forcutting screws or spiralsmuch coarser than the lead-ng

screw the lathe-spindleust be caused to revolvemuch slower than the screw. For most lathes theleadingscrew is made with two threads to the inch that is,it has to revolve twice to cause the saddle andtool to traverse one inch along the bed. Other num-ers

of threads are also used, but two is the mostconvenient for generalwork. If other numbers be usedthey should be even such as 4 to the inch,and 8 to theinch, unless the pitchbe 1 to the inch. Such pitchesas fths or ^thsshould be avoided.It is obvious that, to cut a perfectscrew in thelathe,the leadingscrew must itself be perfect. This,however, is not always the case, even in these daysof * perfectionf mechanism.' And even should thescrew be perfectlyrue in the first place,it does notlongremain so, especiallyn those lathes in which theordinarytraversingmotion is derived from the screw ;as the screw soon gets out of truth and unequallyworn. In most lathes the greater part of the work isdone within a foot or two of the cone centre, or, inother words, there is more short work done than long;and, as only a few inches of the leadingscrew are usedto obtain the requiredtraverse of the rest,it followsthat these few inches are much more used and conse-uently

more worn than the remainder. With a screwthus injuredit is utterlyimpossibleto originater cuta perfectcrew of any pitch. This cause of deteriora-ion

is obviated to some extent by usingthe screw only


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14 LATHES ANJ) TURNING.

when the screw is used for both screwingand traverseturning. The largerand heavier screw-cuttingathesare employed solelyby mechanics; there are manydifferent designs,but that given at Kg. 6, which isSir Joseph Wliitworth and Company's Duplex Lathe,embodies, perhaps,the latest improvements.

Sir Joseph Whitworth and Company also make anexcellent form of Duplex Lathe, Fig.7, which differsfrom the last mainly in being adapted to turn largeshort articles. The bed has an opening,or gap, whichincreases the heightof centres, and provisionis madefor boltingon an additional slide-rest. Screw-cuttinglathes of smaller size and lightermake are employedby mechanics and also by gentlemen amateurs. Oneof this class of good designis given at Fig. 8.

The slide-rests for screw-cuttingand other lathesare made of many varieties. Some are made to slidealong the bed past the headstocks, which is veryconvenient. The headstocks are fastened down asusual, but the slide-rest is fastened to the front sideof the bed. The Messrs. Muir, of Manchester, have apatent for a neat plan of lathe of this sort, in whichthere is a double bed, or bed formed of a casting,,having three longitudinalbars or faces,the centre onebeing rather wider than the others. The headstocksslide upon one of the outside bars and half the insidebar, and the slide rest travels upon the other half ofthe middle bar and the other outside bar.

Ornamental lathes are the ones chieflyused byamateurs; as, althoughthe work to be done in themis not so largeand substantial as that to be done inscrew-cuttingathes,yet it is far more ornamental.


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VARIETIES OP LATHE. 15

delicate,and beautiful. Ornamental lathes are alsoused by ladies ; and, as a great deal depends upon thetaste and lightnessf touch of the operator, it is notunfrequent to see work produced by lady and gentle-an

amateurs which equals,if not surpasses, in beautythat produced by the professionalurner. These lathesare made very light,but very accurate; they aresimilar to the hand-lathe without back gear, the orna-ental

work being produced more by the aid of inde-endentinstruments than by the lathe itself,lthough

the lathe has to be fitted up in a peculiarmanner toallow of these instnunents being applied and con-eniently

used.In addition to these there are many lathes designedfor specialork, or the manufacture in largenumbers

of one article of peculiarshape. Fig.9 is a lathe madesolelyfor turningrailwayaxles. The ends only of theaxle having to be turned, it is put in the lathe, asshown, and both ends are turned at the same time byseparate tools. This lathe is also shown as made bySir Joseph Whitworth and Company.

Fig.10 is a lathe made by Messrs. Fairbairn,Ken-edy,and Naylor,for turningrailwaywheels on their

axles. Both wheels are turned at once, two tools beingemployed on each wheel.

Fig.1 1 is a neat lathe,by the same makers, fo rturningbolts and short work. There are two completelathes on the same bed, and the saddle having only totraverse a short distance,it is moved in a simpleman-er,

as will be seen.The lighterorts of lathe are frequentlyriven by

the operator'soot. This,of course, renders the work


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somewhat more laborious,and until one becomesaccustomed to the unsteadiness of the motion it is moredifficultto producegood work with lathes of this kind.The inconvenience wears off to a great extent afterpracticeand use ; but of course this unsteadiness doesnot affect tools held in the slide-rest.

For many sorts of ornamental work, professionalturners preferto drive their lathes by the foot,becauseof the delicacyith which they can adjustthe pressureand speed. There are many plansfor drivingby foot,but in all the power derived from the pressure is com-unicated

to a shaft underneath by a treadle andcrank. Sometimes the treadle and crank are connectedby connectingods,and sometimes by flatchains passingover the trucks or pulleys.The latter planis preferred,owing chieflyo its havingless friction. If connectingrods or links be used theymust be hooked on to thecrank or treadle pins, so .that,should anythinggetunder the treadle the operator'soot,for instance when beingpushed down, the treadle being stoppedby the obstacle,the Unk shall unhook. Otherwise, ifthe connection were rigid,he momentum of the fly-heel

would urge the treadle down with such force aswould crush the operator'sfoot,or, if the obstructionwere of a harder nature, would fracture or strain someof the mechanism.

In working with foot-treadles of ordinaryconstrue-tion,when the treadingeases, the weightof the treadleand connectingrods, or chains and cranks, causes thecrank to take such a positionthat no pressure what-ver

on the treadle will cause the crank to again move.This positionis known as the * crank being on thecentre.'


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MODES OP DRIVING LATHES. 17

In order to again start the lathe,the operator mustmove the crank off the centre by hand before com-encing

treading. Now, as in ornamental turningitisnot unfrequentlyhe case that both hands are engagedand cannot well be spared,it is very annoying to findthat the lathe cannot be started without havingto moveit by hand ; this inconvenience can be obviated in sosimplea manner, that the wonder is that the plan isnot more frequentlyadopted. By balancingthe weightof the treadle and crank by a counter weight,the crankcan be made to stop at any pointin its circle of revo-ution.

That pointor positionhould be chosen whichis the most convenient for startingi:om. This arrange-ent

has another advantage: it lessens the vibration,and reduces the power requiredto drive the lathe.

The power to be obtained by the treadle is neces-sarilysmall ; but Messrs. Muir, of Manchester, havepatentedand broughtinto use a method of drivingbymany treadles and many feet. The power obtained inthis case of course increases with the number of menemployed in treading. Lathes of considerable size canthus be driven; and the plan is obviouslyof greatvalue on board ship,where men to tread can be hadwithout any extra expense, and where, perhaps,owingto a break-down of the engines,o other power isobtainable. When steam or other motive power is tobe got, no one would think,except in the cases beforestated,of drivingby foot power.

Slide and surfacinglathes are continuallyriven inone direction,and generallyrom a small shaft,calleda counter-shaft,placedover the lathe,and driven fromthe main shaft by a belt. This shaft is either stopped

c


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18 LATHES AND TUENING.

or started by means of a pairof pulleysn the counter-haft,one fastened to the shaft,and the other,termed

the loose or idle pulley,free to run round upon it.When the belt is sUpped on to the loose pulley,thatpulleyis set in motion upon the shaft,but the shaftitselfremains still. When, however, the belt is sKppedon to the fast pulley,ot only does the pulleyrevolve,but, it being fastened to the counter-shaft,the shaftrevolves also. This motion is then communicated froma cone-pulleyn the. counter-shaft,to the cone-pulleyof the lathe-spindle,y a belt passingover both. Inself-actingathes the direction of motion is the same ;but when the saddle of the rest has travelled the whole

lengthof the bed, or as far as is required,t is reversed,or caused to go back again,without either reversingrstoppingthe lathe itself.

Frequently,owever, these lathes are constructed tocut or traverse only in one direction ; and when thesaddle has travelled bs far in that direction as the natureof the work requires,he mechanism connectingitwiththe lathe-spindles thrown out of gear, and the saddlemoved back along the bed by the workman himself.Screw-cuttinglathes are also driven from a counter-shaft,but in a different manner. When the rest and saddlerequireto be reversed,it is usuallydone by drivingthelathe-cone in the oppositedirection,the tool beingthrown out of cut until the motion is again reversed,and the saddle is travellingn the originaldirection.The lathe-cone is reversed by reversing the counteror auxiliarydriving-shaft.here are many methodsof doing this,but the most generalis to have two strapsor leather belts,one passing straightaround the two


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of the saddle is time wasted. It is a good plan,therefore, to make the pulley on the main shaft oftwo sizes, that size which drives the lathe duringits return stroke being made largerthan the other.This has the effect of causingthe return of the saddleto be accomplishedin less time, and consequentlylesstime is wasted.

The belt-guidehaving a considerable distance totravel,the motion of the lever-handle which actuatesthe slide is much too great for ease of manipulation.The belt employed also, if worked hard, gives somelittletrouble by stretchingand breaking; nevertheless,the motion is very noiseless,nd is communicated andreversed without any injuriousshock to the mechanismor work.

In order to do away with the inconvenience arisingfrom the length of travel of the reversinglever,a planhas been devised which effectuallynd in a simplemanner accomplishesthat object,and which is espe-ially

applicableto those lathes in which starting,top-ing,and reversing,re effected by self-actingeans, or

throughthe motion of the lathe itself. In this plan theuse of two straps is retained, and the two loose pulleyson the counter-shaft are also used, togetherwith thedrivingpulleyon the main shaft of either one or twosizes. The loose pulleyson the counter-shaft are, how-ver,

only half their usual width, and no belt-guideisused, the straps always remainingin one place on theirrespectivepulleys. For the fast pulleybetween theothers is substituted a friction-clutch,aused to revolvewith the shaft by being fastened thereto by a featherand groove, which, however, permits it to have a slight


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MODES OP DRIVING LATHES. 21

slidingr longitudinalotion on the shaft. The insiderim of the pulley is turned taper to fit the taperingparts of the iriction-clutch. The clutch is moved by alever to gear with either of the pulleys,or into apositionbetween the two and out of contact with both.In the former case the clutch,and consequentlytheintermediate shaft, partakesof the motion of that pulleywith which it is in contact. In the latter case the shaftremains still. In this plan the motion of the leverhandle is not more than one-third or one-fourth of thatnecessary in the other plan with shiftingelts.

In addition to these, there is also a method fordrivingand reversing,by means of a singlebelt,threebevel wheels and a double clutch. It is, however,much inferior to the two plans described.

IAmateurs are advised to purchasetheir lathes of a 'respectablemaker, and not to attempt to make one forthemselves. It may be generallyonsidered that whenan amateur makes his own lathe although he himselfmay consider it a remarkable work of genius inrealityt will be found to be of littlevalue. This maybe an unwelcome truth to many mechanical aspirants,but it is not the less inexorable ; and I am constrainedto intimate it from having been a spectator of manysuch miscarriages. I have even heard of a woodenslide-rest and wooden ellipticalhuck having been thusconstructed. But these 1 have not seen. J

In purchasing lathe,the tyro must not suppose thatall those made for the same purpose are necessarilyalike. Each maker has his own peculiarstyle,nd al-hough

lathes differ much in design and workmanship,each maker probablyconsiders his own make the best.


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The designof a lathe more especiallyfiects its conve-ienceand usefulness,and the workmanship the quality

and accuracy of the articles manufactured in the lathe.With regardto the workmanship there can be but oneopinion,and that is that it cannot be too good or tooaccurate. Money spent in burnishing,or otherwiseuselesslyrnamenting a lathe is money wasted ; butmoney spent in procuringaccuracy of workmanship iswell invested.

There is a vast difference between good work, ormechanical ornament (ifI may so express myself),anduseless or tawdry ornament. A good mechanic willleave those edges sharpwhich form joints,o that thejoint can scarcelybe seen, whilst terminal edges hewill chamfer or round off,to prevent them hurtingthe operator, or ' being bruised or broken off,and leftraggedthemselves. By judiciouslyhapingthe compo-ent

parts of a machine, he will contrive to givethewhole a graceful,inished,and mechanical appearance,which would otherwise be wanting,and this he doeswithout extra expenditure,and without impairingtheusefulness of the machine. Whereas another will cut anumber of beads and mouldings on his work, burnish agreat portionof it,make as much of the machine aspossible bright,'nd paintthe unpolishedr * black 'portionof some flamingcolour, and daub it with giltor bronze. This he does imagining he improves theappearance of his work, whereas he impairsit. Thebeads and sharp edges and anglesweaken the articleconsiderably,and, in course of working, they arccertain to be bruised and indented in some way,and the hand seems always to be knoclsiinggainst


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ON CHOOSING A LATHE. 23

them, and being cut or scratched. They also serve asreceptaclesfor dirt. Burnishing machinery usuallyhas the appearance of being done to cover defects,and the style becomes what is known amongst me-hanics

as *deep scratch and high polish/ Gaudycolouringsoon loses its bloom, but in whatever stateit may be it impartsto the mechanism such a tawdryappearance as to excite the ridicule of every sensibleman.

As to the design of a lathe,that depends so muchon the fancyof the user, and is so much a matter ofopinion,hat it is difficult to laydown many arbitraryrules. When one is accustomed to use a lathe of

any particularesign even though it be in reaUty abad arrangement being famiharised with its defectsand inconveniences, one is apt to overlook its badfeatures,and be prejudicedin its favour. The follow-ng

may, however, be mentioned as a few of the mainpointsof a good lathe :

1. It should be constructed wholly of metal, foralthoughsome are of opinionthat the introduction ofwood is advantageous,as preventing that injuriousjarringor * chattering'which frequentlyannoys theoperator, and renders it difficult for him to producegood work, I believe the notion to be almost explodedamongst mechanics ^thechatteringeingalwayscausedby the weakness of the mechanism or by the inattentionor the imskilfulness of the operator.

2. The various parts should be as strong and massiveas possible,ithout clumsiness.3. The bed should be thoroughlyunyielding,ndstand immovably firm and level.


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4. The spindleshould be of good size,and its bear-ngsnot too close together.

5. Conical bearingshardened are perhapsas good asany. When well made, with proper care and occasionalregrinding,they will last a long time, and give butlittletrouble ; but if left unlubricated,screwed up tootightor improperly,r if the metal of the headstockyieldto the pressure of the screw, then in either casethe necks *bind,' get hot, abrade, and cause greattrouble and annoyance.

6. The startingand reversinghandle should bewithin easy and convenient reach of the operator.

7. The slide-rest should have a motion independentof the ordinaryscrew, for throwingthe tool in and outof cut. For screw-cuttinghis motion is very valu-ble.

8. The tool-holder should be one of those allowingthe tool to be placedat any angleor convenient posi-ion

on the tool-plate.9. All wearing or working surfaces should be pro-ided

with oU holes for lubrication,and those holeslikelyo get filled with dust or gritshould be furnishedwith proper stoppers.

10. All slidingurfaces should be scrapedto a goodbearing,and without grinding.

There are certain technical terms and expressionsused by turners which should be understood by learners.These terms vary accordingo the locality,ut I beUevethe meanings here given to them are those most gene-ally

received.* Traverse turning,'traversing,'nd * sliding-up,'

are the expressionsvariouslyused to denote those


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TECHNICUi TERMS. 25

operationsin which the tool is caused to move alongthe lengthof the bed, the tool being set either parallelor nearlyso to the line of centres, and by which thework produced is of the same size throughout,ornearly so.

* Surfece- turning,'surfacing,'nd * facing-up,'reused to denote those operationsn which the tool doesnot slide along the bed, but across it,at rightanglesto the line of centres, and in cuttingproducesa planesmrface.

' Burr,' * fash,'and * raw-edge,'re generallysed todenote the edge or angleof junctionof two cuts, at rightangles,r less than rightangles,o each other. Suchedges are usuallyrather sharp,or wire-edged,and jfre-quently inflictserious cuts and gashesin the workman'shands, should he happen to touch the edge whilst thework is in motion. When cuttingholes in metal theorificesof the hole, and espedaUy that one from whichthe point of the tool makes its exit when cutting,refrequentlyexceedinglysharp and dangerousto touch.

' Trueingup ' is the expressionused to denote turn-ngup an article for the sake of having a smooth

surface, and without regard to size,and would beaccomplishedwhen the rough castingor forginghadall the black or scale turned off.

*Hold up to size,'r *not to hold up to size.' Whenan objecthas been turned to certain dimensions, if allthe black or scale is turned off,it is said to ^ hold upto size ;'but if when the proper dimensions are attained,patches of scale are still seen, the article is said ^ notto hold up to size.'

* True,' * out of truth.' Sur ces are said to be * true '


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26 LATHKS AND TURNING.

when smooth and level,cylindershen perfectlyylin-rical,and so with other shapes. Articles are said to

* run true ' when, in the case of a surface, the surfacerevolves in a plane at right anglesto the centre oflathe spindle,and in the case of a cylinderwhen itrevolves concentrically.

* Chattering,'r * shattering,'s the characteristicterm apphed to a peculiarnoise,made generallybythe rapid vibration of the article turning. The noise isvery unpleasant.When once heard it is not soon to beforgotten,nd it is a tolerablyure signthat somethingis wrong. Work produced while this chatteringisgoing on is usually' out of truth ' and wavy.

' Thread ' of a screw is that part raised above thesurface of a cylinderupon which the screw is cut.Screws may have several threads.

The * pitch of a screw isthe distance from thread tothread, or the longitudinalistance which the threadadvances in one revolution of the spindleupon whichthe screw is cut.

'Drunken pitch'is the term used to denote a badlymade screw. When the thread advances faster duringsome portionsof a revolution than at others,or a screwhas an uneven pitch,r one not uniform, it is said todrunken.

' Centres ' are the indentations made at the endsof articles,for retainingthem in place whilst beingturned.

' Catch in * is the expressionused when the tool incuttingsuddenlyjerksdeeperinto cut, and either digsout an irregularole in the material,or throws it outof the centres, or jerks the tool out of the operator's


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PAET n.

PDAIN TURNING WITH HAND-TOOLS.

In order to describe the simplestoperationsfirst,Ishall commence with instructions for plainturningwithhand-tools in the simplelathe. It is necessary that theoperator should have a good knowledge of the use ofthese tools before he can become a good workman ateither the slide and screw-cuttingathes,or the orna-entallathes. In the working of slide-lathes,ndothers of that sort, it is frequentlyecessary to makeuse of a hand-tool to touch out some corner or curvewhich it is difficultto come at properlywith the toolsin the slide-rest. It is also far easier to judge of thecorrect shape and method of using tools in the slide-rest when one thoroughly understands the cuttingaction of hand-tools. As these tools are held in theoperator'shands, and guided by him, he very soonfeels when they are out of order, or applied in thewrong position.But when tools do not cut arightin the slide rest, the workman has to rely on hissightalone to inform him of the fact,and this to theinexperienceds seldom sufficient.

In ornamental tiuning,hand-tools are stillmore fre-uentlyrequired,nd for this work especially,houldthe operator be able to use them with dexteritynd

certainty,s the slightestlipor clumsy touch would


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PLAIN TURNING WITH HAND-TOOLS. 29

result probably in the work being spoiled. The pri-arylessons should be learned upon a rough or strong

lathe of some sort, as, although it may appear theeasiest thing imaginable to use these tools, it is,nevertheless,generallyfound upon trial that some ofthem ^unless carefullyused are extremely apt toplay awkward tricks.

I do not mean to say that the difficultys verygreat, because it is not: with cautious handling nomishap need occur. But it is,however, desirable toguard againstaccidents,which, if they were to happen,would perhaps damage beyond repair the delicatemechanism of the ornamental lathe. Those who aretotallyunacquainted with turningshould at firsttakea few lessons Irora a proficientn the art, acquiringbythis means much rudimentary but necessary know-edge,

which could scarcelybe gathered from a book.There are many professionalurners who make it theirbusiness to teach amateurs in all branches of the art,and also to procure for them the necessary fancywoods, and any instruments they may require. Ithink the present work will furnish the reader withmost of the information these gentlemen could com-unicate

; but I would, nevertheless,advise beginnersto attentivelyatch the movements of a good turner,as, by this means, they will best be able to form anidea as to how they should proceed themselves.

The lathe itself having been previouslydescribedand illustrated at Fig. 2, I shall proceed to describethe chucks or instruments for communicating themotion of the lathe-spindleo the work. Thesechucks or drivers are screwed either on to the male


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30 LATHES AND TUBNIKG.

screw on the spindleend or *nose* of the lathe, orinto the female screw of the spindle. Chucks are notonly necessary for giving motion to the work, but insome cases for firmlyfasteningnd holdingthe materialin a convenient positionfor allowingthe tools to beapplied to it As the articles to be chucked varyg^tlyn rize,.hape,.d m.. u l, Ae chuck, n.Zbe constructed variously.Many will,however, answerequallywell for hard and soft woods, and ivory.A fewcan be used indiscriminatelyor these materials andmetals,but, as a rule,metals requirechucks of greaterstrengthand different construction. The drill-chuck,

Fie. 12. Fig. 13.

Fig.12, is made either of brass or cast or wrought iron.The dotted lines denote that it is fitted with a femalescrew for screwing on the spindleend. It also has ataper square, or taper round hole to receive a set ofdrillingools,and also the two drivers.Pigs.13 and 14.Fig.13 is the prong driver for the softer varieties ofwood. Fig.14 is the cross kerf driver. Both are madeof steel,nd the latter isused mostlyfor the hard woods,ivory,bone, and small work in metals. When thesedrivers are used, the work is alwayssupported at theother extremityby the screw centre. The taper-screwchuck. Fig.15, is made of metal, and screws on themale screw of the mandril. The taper-screw itself is


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PLAIN TUMPING WITH HAND-TOOLS. 31

made of steel,nd is fastened to the body of the chuckby a screw thread,so that if the screw be broken off ordamaged, another can be substituted. This chuck isused for either soft or moderatelyhard woods. It isnot well adaptedfor hard wood or ivory,althoughit isoccasionallyade to answer for them. Any attemptto chuck metals with it would result in the breakingor spoilingf the screw. Generally,his chuck is usedfor holding piecesof wood from half an inch to sixinches in thickness. Thinner pieceshave not sufficientsubstance to givethe thread the requisiteamount of

Fie. 14. Fie. 16.

holdingpower. When the wood exceeds six inches inlength,it must be supportedat the other extremitybythe centre, or by a proper bearing or stay. This chuckmay be very convenientlyused when it is requiredto turn any recesses in moderately thick pieces ofwood; but when this has to be done in the case ofvery long pieces,tis inconvenient to support the otherend by the screw centre, as that centre would then bein the way of the tool. In cases such as this,theexterior should be turned, whilst the end is supportedby the centre. This, of course, can be done withoutinconvenience; the centre is then removed, and the


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work supportedby a wooden bearing,whilst the in-erioris being operatedupon, and the requiredrecess

or cavityturned out. A piece of wood is then madeto fit the mouth of this cavity,nd to form an abut-ent

for the centre while the outside is being finished.If the cavitybe sufficientlyarge to allow the centreand the spindleto enter, the former may be forced intothe wood at the bottom of the cavity. In this case nostopper is required.

Sometimes, after the cavityis made, itis requiredtoremove the work from the chuck, and change endswith it,in order to get at the end which hitherto hasbeen against the chuck. In this case, remove thework, and on to the same chuck screw a pieceof thinflat wood, which turn down to the size of the mouthof the cavity,r to fitthe cavity rather tightly.Thearticle being then gently pushed on to this stopper,and the centre forced into the hole made by the taper-screw, the work may be finished with ease. When thisplan is followed, the end of the article on the stopperor chuck, as well as the cavity,s certain to run as' true ' as may be required.

The five-pinr plate-chuck.ig.16, isalso of metal.It screws on the mandril end, and its body or * boss 'is of the same shape as the chuck last described,onlyinstead of being furnished with a taper-screw, it hasfive steel pinsor pointsprojectingrom its face. Thesepins are arranged as is shown in the figure. Thischuck is used almost wholly for holdingthin piecesofsoft wood.

The cone-chuck is made of metal and screwed onthe spindleend. Its construction will be understood


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PLAIN TUBNIKG WITH HAHD-T00L8. 33

by referringto Kg. 17, The projectingpin a is ofsteel,and has a screw cut upon It to receive the nutb. The cone c is also of metal, but sometimes fortemporary use it is made of hard wood : it slides onthe pin a. This chuck is used for turning pieceaofwood of large diameter, and having a hole throughthem. Articles of this sort are by ite means chuckedtrue or concentric with their central holes. Theuniversal mandril, Fig. 18, is used for the same de-cription

of object as the last,than which for manypurposes it is somewhat better.

Fi6. 18. Pre. 17.

The mandril a is of steel,the ends are carefiillyhardened, and are furnished with centre holes for run-ing

between the ordinary lathe centres. It is drivenby means of a carrier or driver. The mandril isscrewed throughout almost its whole length,and isfitted with a nut b, and washers c c. When it is re-uired

to turn any article having a hole through it ofa size for which the operator has no mandril, a pieceof hard wood is taken and bored through with a holerather smaller than the mandril thread. This woodbeing then twisted on the mandril, a thread is formed


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purpose especiallyt is very useful. Four or fivescrews, such .as are shown at Fig.A, are made to fitincommon all the holes in the plate.

Any rough piece of wood which it is wished tofasten to the plateis laid on its face,and two or moreholes,in convenient positions,re made in the woodby a gimletpassingthrough the holes in the platefrombehind. The screws are then used to fasten the one tothe other. These should be inserted in such positionsthat they may take into those parts of the wood whichdo not require turning,and not into any place wherethey would projectand be in the way of the tools.The holes being made all over the plategive everychance of the screws being properlyarranged.Temporary chucks, for which this plateis used asan attachment, are merely cavities turned out of asohd piece of wood fastened to the chuck-plate,sexplained. The recess or cavity or it may be a pro-ection

to take into a cavity ^is turned so that thearticle may fit it rather tightly.Such chucks as theseare frequentlyrequired: they are principallysed forholding half-turned articles whilst they are beingfinished.

The work to be chucked may be of either hard orsoft wood, or ivory,c.; but these chucks do notpossess sufficient holding power to answer well formetals,although a chuck of hard wood is sometimesused to hold small spheresof brass whilst being turned.Wooden cup-chucks are very inexpensive,they areeasilyand readilymade, and do not damage the toolsshould theyinadvertentlye allowed to come in contactwith them. The great objectionto their use lies in the


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liabiUty,r rather certainty,f their shrinking,arp-ng,and gettingout of truth and out of shape. For

this reason chucks of universal use are made of metal ;but when, as is frequentlyhe case, a peculiarchuck isneeded for only one or a few articles,nd, these done,it is of no further service,the wooden chucks are farpreferable.

Spring chucks are tnade of either box-wood ormetal, and screw on the spindle-end.They are formedin several parts or staves,somethinglike a cask. Thesestaves, having considerable elasticity,pringopen ; sothat an article to be held by one of the chucks beinginserted in the mouth of the chuck, and the stavescompressed upon itby means of ringswhich encompassthe staves, is held whilst being turned. These ringsare sometimes made to compress the staves by beingslid towards their largestdiameter. And sometimesthe outside of the staves is screwed, and the ringis alsocut with a correspondingscrew ; the staves are thencompressed by twistingthe ringround so as to advanceit towards the largestdiameter of the chuck. In somecases these chucks are very convenient, but as theyhave onlylittlepower of variation in size or expansion,their use is necessarilyimited. Some turners, how-ver,

have such a great likingfor them that they keepthem in all sizes. In most cases, a chuck turned froma solid pieceof wood fastened to the chuck-plateillbe found to answer just as well. Split or springchucks are used for wood and ivory,and occasionallyfor metals.

There are numbers of other chucks used by turnersin wood and ivory,but those described are probably


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amongst the best and most generallyuseful. Manylathes are furnished with chucks in great number andvariety,ut, as a rule, one half of them are utterlyvalueless and never come into requisition.It is a badplan to buy too many chucks with a lathe. Turnerswill find it much to their advantageto purchaseat firstonly those which are of great use and extended appli-ation,

and to add other chucks as they find theyrequirethem.

Most good lathe-makers make all their work tostandard sizes, and use standard Whitworth screwthreads; so that any chucks purchased even yearsafter the lathe,can generallybe relied upon to fitthespindleand * rim true.'As before mentioned, chucks are usuallymade ofmetal ; for the larger sorts cast iron is the bestmaterial,but for some of the smaller ones, wroughtiron is to be preferred. Brass is frequentlysed forboth large and small chucks; but, beyond its non-iability

to rust, it possesses no advantage over iron.On the other hand, it is much more costly,t is moreeasilyruised and indented,and is much more trouble-ome

to keep clean. The hands of the workman arealso somewhat soiled by touching brass,and this doesnot conduce to the productionof dean and unsoiledwork.

Chucks are generallyput on by hand, the threadsof the screws being well fitted,but not made so tightas to prevent this being done. The usual mode isafler removing the centres and clearingaway all dirtfrom the spindle-endnd also from the chuck itselfto hold the mouth of the chuck againstthe nose of the


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PLAIN TUENING WITH HAND-TOOLS. 3^

Spindleby the right hand, the left hand being at thesame time applied to the driving-strap,nd thecone and spindle caused slowly to revolve in thesame direction as for turning. After a chuck hasbeen used for any but very lightwork, it will be foundto be jammed up againstthe collar of the spindletootightlyo allow of its beingstarted by the hands. Thechucks, therefore,are all furnished with some means forapplyingthe power of a lever to unscrew them. Thosedescribed are shown with a small hole in the bosses, inorder that they may be removed by the pin and circlewrench, as shown at Fig. 22. This method is as neatand convenient as any.

Some tiuners are in the habit of takingup a drillor an old piece of iron and forcingit into the pin-

Fio. 22.

holes; but this is a very bad practice,and is onlyfollowed by careless workmen. When this slovenlymethod is resorted to, the pin-holesoon becomesbruised out of shape,and so much enlarged,hat theproper instrument is rendered useless. Taper-pinsarenot good instruments to use for this purpose, and theyshould be discarded,except in those cases where butlittleforce is required,and that not frequently.

The tools requiredfor turningsoft woods are veryfew and simple. The professionalturner seldom usesmore than half a dozen, and with these he can manageto produce a' great varietyof work. The bobbin or


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40 LATHES AND TUKNINQ.

spoolturner, with the aid of one tool only the gouge,and occasionallyhe gouge and chisel ^will turn outtwelve dozen or more of the bobbins used in spinningand other factories in one day. That number isgenerallyconsidered a da/s work. It can thereforebe readilyimagined that there is no time to wastein putting down one tool and taking up another.Although a workman does so much, he seldom appearsto be in any violent hurry, but continues his workalmost with the easy celerityand regularityof amachine. These tools,besides being so few, are fre-uently

very rough,and they are usuallysurpassedinthat respect by the lathe ; yet an amateur, with thebest of lathes and any number of tools,would scarcelysucceed in doinghalf that quantityof work. Indeed,I am inclined to think that he would consider it a verygood day'swork if he had completed one dozen or onetwelfth the number.

It will be understood that the above refers only toturning in soft wood. Turners in hard woods andivory require a much more extensive Collection oftools ; and the number is never complete,but requirescontinual additions for the variation in the nature ofthe work to be done. Many sorts of work requiretools of such peculiarshape that they are only usefulfor that purpose for which they were designed. As,however, these differ only in shape but are alike incuttingprinciple,t would be unnecessary if it werepossible to describe all those used. When theoperator becomes acquaintedwith the peculiaritiesfa few of the principaltools,he will seldom have muchdifficultysupposing him to be possessedof a due


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PLAIN TURNING WITH UAKD-TOOLS. 41

amount of common aenae inwill enable him to satisfactorilyof work he may have in hand,rallyin use for soft woods arethe gouge Fig 23, chisel Pig.25, diamond point, or V toolKg. 27, cranked point Fig. :

contriving tools whichexecute any description

The tools most gene-those shown ; namely,24, scraping chisel Fig.Fig. 26, cranked chisel38, cranked round Fig.

Fio. 20. Flo. 27.

12d, and parting tools Fig. 30. The gouge and chiselare those in most frequent use. These differ altogetherfrom those used for hard woods and ivory; but theothers do not differ so much, being of similar shapesomewhat differentlyround.

The hard-wood tools are shown at Figs.31 to 50.The uses of these tools wiU be spoken of presently.


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42 LATHES AND TURNINQ.

I may, however, mendoii here that, although to theinexperienced eye the tools may appear to be so verymuch alike that they may be used indiacrimmatelyfor hard and soft woods, that is not the case. Theydo differ materially. If the soft-wood tools be used

for hard materials, their edges will very soon not onlybe blunted, but knocked off altogether and they willrequire considerable regrinding before they can againbe applied to their legitimatese. On the other hand,

when hard-wood tools are used upon soft substances,although the tool may not get damaged the work does,as it cannot be done nearly so smooth as with theproper tools. The woody fibres do not get cut or


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44 LATHBS AND TURNING.

entirely,and is the result of their own careless andslovenlygrinding. On examining the tools,it ia foundthat, uistead of the cutting edge being formed of twoetraightsurfaces,or one straightand the other con-ave,

as it should be, it ia ground with convex surfaces,Fie. 46. Fia. 47.

tlor surfaces formed of such a collection of curves that Iam not sufficiently geometrician to give a name tothem. The same tool, ground by a careftil person,will work as well as can be wished.

Fie. fil.

Should the operator be unable to judge of the properangles by the eye, it will be better for him to cut outa piece of thin sheet-iron or brass to fitthe tool whenproperlyground, and to grind the tool to this gaugewhen it gets out of order.


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46 LATHBS AND TUBNINO.

turning latbe, such as that shown, and adapted only tothat kind of work, then no alteration of rests is required.If the lathe be one with a slide-rest,nd we wish to exe-ute

any hand-turning,it ia generallythe better plan toremove the slide-rest altogether. But if the lathe be aslide and screw cutter, the slide-rest cannot at all timesbe removed so easily. It is not, therefore,worth whileto be at the trouble of removing it,unless absolutelyin the way, or the turning to be executed will occupya considerable time. When this is the case, themoving or screw headstock should be taken off,andthe shde-rest altogethertraversed along the bed untilpast the place where the headstock is to be fastened.

The headstock is then replaced,and aFio. 54. rest-holder and rest placedon the bed

between the headstocks, and fasteneddown in any convenient position.Thisrest-holder and rest is similar to theone shown in positionn the lathe-bedat Fig.1, and needs no separate illus-ration.

It can be moved anywhere along the bedof a lathe between the headstocks, can be placed atany distance from the hne of centres to accommodatedifferences in diameter of the work, and can also beplaced at any angle to the line of centres. The rest, ortee, can also be raised to any height,for the better ac-ommodation

of any of the tools,and can also be setwith the edge of the rest either parallelto or at anangle with the line of centres, as is found most conve-ient

for the work in hand.Care must always be taken that the rest-holder be

firmlybolted to the bed of the lathe and the rest, and


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fiwleoed tightin ite socket before the work ia com-enced.It may otherwise result in a serious smash of

the tools,of the work, or of the operator's fingers.A pair or two of different sized callipersare also an

indispensablepart of a turner's collection of tools.Those shown at Kg. 55 will be found of convenientconstruction. They are used as gauges for turning toany particularsize,and the same pair answers equallywell for measuring either internal or external work.In Fig. 55 they are set for external and at Pig. 56 for

internal meaauremenfa. Those illustrated at Fig. 57are of capital construction, but they are not welladapted to soft woods indeed, they are seldom usedwith woods at all,but principallyor metal. The pe-uliarity

of these consists in one of the 1^ beingformed to act as a spring,so that when appUed to anyarticle which is not turned small enough, the spring1e^ opens.Attached to the lower part of the leg is a pointerextending up the aide of the leg aa shown ; the ex-


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tremityof this pointer is made by the springingutof the leg to indicate the extent the article is abovethe requiredsize. I believe that these calliperseredevised by a workman at the establishment of Messrs.Penn Son at Greenwich, and am inclined to thinkthey would be much more used were they betterknown.

The gauge is formed of a graduated slipof steelslidingn a stock of either the same material or bra?s.This is used to measure the depth of holes,cavities,rrecesses, and for other purposes. Another convenientinstrument is the temporary tool support, or arm-rest,which is simply a piece of steel with its end crankedup for about half an inch. It is set in a handle, andis used with the cranked part up, on the ordinaryhand-tool rest, as a temporary or moveable support for thetool,and to obviate the continual necessityf shiftingthe rest itself.

The woods chieflysed for plainturningare alder,applewood, box, beech, holly,lignum vitaB,mahogany,and pine. A great many other woods are used, butchieflyfor ornamental purposes, and then more fortheir rarityand colour than for any other superioritythey possess over those above mentioned. Amongstthe more beautiful sorts are the African black wood,black and green ebony, cam wood, Spanishyew, kingwood, c. These, and a multitude of other sorts, canbe procuredof dealers in foreignwoods in wholesalequantities.They can also be purchasedin small lotspreparedfor the lathe in various sizes,of almost anysmall-lathe and tool maker. Many of the sorts, how-ver,

are rather expensive and therefore the tyro will


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very similar in texture to some of the hard woods, andis easilyturned by the same tools,and in a mannersimilar to hard wood ; but being more expensivethaneven the fancywoods, care should be taken that thereis no unnecessary waste of material in working it.

Besides these substances, there are others used bythe ornamental turner. Amongst them may be men-ioned

jet,cannel coal, bone, glass,Derbyshirespar,cocoa-nut shell,coquillanut, ivory nuts, and india-rubber the latter both in its usual state and vulcanised.These can be turned with the tools used for the variouswoods and metals, but they each require pecuhartreatment. Woods differingn density,besides re-uiring

different tools,require different treatment inother respects. In the matter of speed lies one greatpointto be observed by the turner : but this is a pointwhereon authorities differ greatly. For instance,whenturningsoft wood, some advise that it should be run ata few hundred feet per minute, and others at as manythousand. Many also are of opinionthat it cannot berotated too rapidly but this is a mistake. It is verywell known that when a tool is appliedfor some timeto wood in rapid motion, the tool gets hot from thefiriction,he extreme edge becomes of a blue colour,which indicates that its temper is reduced,and its cut-ing

power is damaged. We judge fix)m this that themotion is too rapid,and we reduce it accordingly.Ifthe tool be apphed intermittently,hat is,appliedto thecut for a few seconds, then removed for a short spaceand re-applied,he wood may be revolved much fasterthan if the cuttingwere made continuous. Thisobviously arises from the ct of the tool being


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instruments,I will endeavour to givefuller informationas to the method of usingthem in actual practice.Tothis end it wiU be as good a plan as can be adoptedif a few examples be chosen, and the various steps tobe taken and course to be pursued in turningthembe fiillyetailed and explained.In order to communi-ate

as much information as possible,hese examplesshall be of as varied a nature as can be chosen fromamongst those of any use, and I will endeavour so todescribe the mod/us operandithat even those personswho have not had the advantage of seeingsuch workperformed, shall stillbe able to form a tolerablyor-ect

idea of the method of proceeding.The First example shall be very elementary. Wewill suppose that we require to turn a cylindrical

piece of wood, say 12 inches long and 4 inches indiameter, the wood to be one of those in the class ofsoft woods. First,select a piece of the requiredsortof wood, largeenough to contain the cylinder,ut aslittle above that size as is obtainable. If this piecehave any rough projectionsr corners, they should bechopped off with a hatchet. The inexperiencedurnerwill find it easier to judge of this if he take a pairof compasses and finds the rough centre of each end ofthe wood, and from that centre draws a circle ratherlarger m diameter than the cylinderis to be turned.By roughlychopping away the wood outside the circleat each end he will bring the wood somewhere aboutthe requiredshape. This chopping is not absolutelynecessary, but the shapingis more quicklydone in thismanner, whilst the chances of knocking off the edgeof the tool are much lessened.


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If the centre be fixed in the hole of the lathe spindle,it must be taken out, or if any other chuck be on thespindleose it must be removed. The drill-chuck canthen be screwed into its place,and the prong-driver.Fig. 13, put into the hole of drill-chuck. The centreof one end of the wood is then placed against thecentre of the driver, and held there by the left hand,whilst the right hand pulls the shiftingheadstockalong the bed up to the work, and then fastens itdown on the bed. The hand wheel of the headstockis turned so as to force the centre pointof the spindleinto the centre of the end of the wood, the pressure atthe same time forcingthe prongs of the driver into theother end of the wood. The greater the depth towhich the driver is embedded in the wood, the morepower it will drive,or the heavier the cut it will takewithout slipping.Unless forced in tolerablyeep, aheavy cut, or sudden jerkcaused by the tools ' catchingin,'will cause the prong to slipand act as a drill,cuttinga round recess, instead of a simpleindentation. Occur-ences

of this sort should be avoided as much as possible,as, although no great injuryis done to the lathe orchuck, the work isrendered untrue, and would probablyrequirere-turning.After the centre and the driver areproperlyforced up, the pressure should be taken off,and the centre justremoved from that end of the woodto allow of a drop of oil beingput into the indentationof the centre. The lathe should then be pulledrounda few times by hand, whilst the rest holder and the restare adjustedconvenientlyn positionnd height. Bymoving the lathe in this way an accident of otherwisefrequentoccurrence is prevented,s ifthe wood be at all


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54 LATHES AND TDBNING.

irregularn shape,or run out of truth,and the rest beadjustedclose to the placein the wood having the leastradius,it is obvious that on startinghe lathe the partof greater radius will come round into contact withthe top of the rest,and the belt drivingthe lathe willeither slip,r the wood be burst from its centres, andprojectedwith force into the operator'sace,or perhapsthrough a window, if one be near. This occurrenceshould be avoided even more carefullyhan the last.

Take a pairof callipers,ig. 55, and set them by agraduated straightedge or rule to the required dia-eter,

namely four inches. Set the lathe in motion,at the rightspeed,and apply the gouge. Fig.23, to thewood, until the whole lengthis reduced nearlyto therightsize,as indicated by the caUipers. When down,the rest will probablybe too far from the work, andrequirere-adjusting.he chisel,Fig.24, or the scrapingchisel.Fig.25, is then to be apphed till the calliperswill justdrop over the work.

It must be remembered that,for a pairof caUipersto gauge properly,they must be appliedto the workpreciselyt rightangles with the line of centres. Ifheld ever so slightlycross, the indications will be in-orrect,

as the work will necessarilyave to be turnedtoo small, to allow the calliperegsto pass over ; thehypothenuse of a right-angledtrianglebeing greaterthan its base.

And now a few words to explain the manner ofholdingand applyingthe tools whilst turningthe wooddown to size.

The tools beingplacedin suitable handles ^Fig.8VB a good shape ^theyre graspedby both hands, the


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PLAIN TUBBING WITH HAKD-T00L8. 55

left being placed on the tool itself,ot for from thecuttingedge, and the rightupon the end of the handlefiirthestfrom the edge. The cuttingend is then placedon the rest, and iQclined upwards, something likeFig. 51. The left hand is presseddown uponthe tool so as to keep it firm upon the rest,and suffident pressure is put at the end of thehandle by the right hand to keep it steady incut. The tool is traversed or guided alongthe rest by the left hand, but the point isforced into the cut, and raised or lowered bythe right.

All the tools ^whether for sending orcutting are held in a similar manner, butthose for scraping are placed upon the restand applied to the work horizontally,sshown at Hg. 52. The chisel.Fig.24, shouldnot be used as a scrapinginstrument, not beingadapted to that work ; but the scrapingchisel,Fig. 25, may be used in that manner with good effect,if the edge be kept very keen and smooth. Whenusiog the scraping tools,the rest must be lowered toallow the top of the tool to come level with the centre.The chisel.Fig. 24, should be held inclined as at Fig.51, with its cutting edge oblique to the axis of thework.

The work in hand is not yet finished,however, as ityet requires to be made of the right length. Takethe gouge, lay it on its side on the rest, with its bottomtowards the end to be cut off,and its point inclinedrather above the centre of the work. Qrasp the end ofthe handle firmlywith the righthand, if turningdown


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overcome as soon as possible,ecause every movementof the sort is fatal to the productionof true work. Agood workman, however rough the wood may be, canmanage to hold his tools as firmlyas if held in theslide-rest. By firmness is not meant rigidity,ut asort of elastic steadiness of the tool on the rest, whichproduces good work with littledamage to the tools,and Httle exertion on the part of the workman. Thereader m ^ find it somewhat difficult to understandthe difference here indicated,but he will soon discernit if he carefullybserve two turners, one good andthe other bad, at work. Soft woods are renderedsomewhat smoother than when only turned, either byholdinga sheet of glass-clothgainstthe wood whilstit is in rapid motion, or by taking a handful of fineshavings,and pressingagainstthe revolvingsurface.Curved portions are smoothed over beautifullybypressingthe flat part of the gouge againstthem, whilstin motion in the lathe. The gouge must be firmlyheld, so that, although not cuttingat all,it is nearlyon the point of cutting,nd when moved along care-fiiUyover the surface of the wood it has the effect ofbm'nishingthe work, by compressingthose fibres on theimmediate surface. Such polishisgenerallyore lastingthan that obtained in other ways. It is possiblehatthe absolute truth of the work may be somewhatimpaired,but not to any appreciablextent.

The rest of the soft-wood tools are used in thesame manner as those for hard wood, and I will there-ore

choose the next example of the latter material.Let the example selected be the stem of a vase orpedestal,f the shape given at Fig. 59 ; its extreme


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58 LATHES AND TDENING.

dimensions being, say, 6 inches long and 1 inch indiameter. Choose a piece of wood and cut it outroughlyto a cylind

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A Treatise on Lathes and Turning Simple Mechanical and Ornamental 1000177405