Central Machinery 33684 User manual

7” x 10” Mini Lathe
Model 33684
Assembly and Operating Instructions
3491 Mission Oaks Blvd., Camarillo, CA93011
Copyright 2000by Harbor FreightTools®. Allrightsreserved. Noportion of this
manualoranyartworkcontainedhereinmaybereproducedinany shape or form
withouttheexpresswrittenconsentofHarborFreightTools.
For technical questions and replacement parts, please call 1-800-444-33534.
®

Important Safety Instructions
READALLINSTRUCTIONSAND WARNINGS BEFORE USINGTHIS TOOL.
Operator
COMMON SENSEAND CAUTIONARE FACTORS WHICH CANNOT BE BUILT INTO
ANYPRODUCT. THESE FACTORS MUSTBE SUPPLIED BYTHE OPERATOR. PLEASE
REMEMBER:
1. Whenusingelectrictools,machinesor
equipment,basicsafety precautionsshould
alwaysbefollowedtoreducetheriskof fire,
electricshock,andpersonalinjury.
2. Keep work area clean. Cluttered areas
inviteinjuries.
3. Considerwork area conditions. Do not
usemachinesorpower tools in damp, wet,
orpoorlylit locations. Do not expose
equipmenttorain. Keepwork area well lit.
Donotusetools in the presence offlam-
mablegasesorliquids.
4. Keepchildren away. Allchildrenshould
be kept away from the work area.
5. Guardagainstelectric shock. Prevent
bodycontactwithgroundedsurfacessuchas
pipes,radiators,ranges,andrefriderator
enclosures.
6. Stayalert. Never operate equipment if
youaretired.
7. Donot operate the product ifunder the
influenceofalcoholordrugs. Readwarning
labelsonprescriptionsto determineifyour
judgmentorreflexesmightbeimpaired.
8. Donot wear loose clothingor jewelry as
theycanbecaughtin movingparts.
9. Wearrestrictivehaircoveringtocontain
longhair.
10. Useeye andear protection. Always
wear:
-ANSIapprovedchemicalsplashgoggles
whenworkingwithchemicals.
-ANSIapprovedimpactsafetygoggles at
othertimes.
-ANSIapproved dustmask or respirator
whenworkingaroundmetal,wood,and
chemicaldustsandmists.
-Afullface shieldifyouareproducingmetal
orwoodfilings.
11. Keepproper footing andbalance at all
times.
12. Donot reach overor across running
machines.
13. Alwayscheckthatadjusting keys and
wrenchesareremovedfrom the tool or
machineworksurfacebeforepluggingitin.
14. Donotcarryanytool with your finger on
eitherthestartbuttonor trigger.
15. Whenservicing,useonlyidenticalre-
placementparts.
Before Operation
1. Besure the switchis OFF whennot in use
andbeforepluggingin.
2. Donot attempt touse inappropriate
attachmentsinanattempttoexceedthetool’s
capacity. Approved accessories are available
fromHarborFreightTools.
3. Checkfor damaged parts. Beforeusing
anytool,any part thatappearsdamaged
shouldbecarefullycheckedtodetermine that
itwilloperateproperlyandperformitsin-
tendedfunction.
4. Checkforalignmentand bindingofall
movingparts,brokenparts ormounting
fixturesandany otherconditionthatmay
affectproperoperation. Any part that is
damagedshouldbe properly repaired or
replacedbyaqualifiedtechnician.
5. Donot use thetool if any switch does not
turnoffand on properly.
SKU #33684 Page 2

Operation
1. Neverforce the tool or attachmentto
dothework of a larger industrialtool. Itis
designedto do the job betterand more
safelyattherateforwhichitwasintended.
2. Do not carry the tool by its power
cord.
3. Alwaysunplugthecordbytheplug.
Neveryankthe cord outofthe wall.
4. Alwaysturnoffthemachinebefore
unplugging.
IFTHEREIS ANYQUESTION
ABOUTA CONDITIONBEING
SAFEOR UNSAFE,DO NOT
OPERATETHETOOL!
Grounding Instructions and
Voltage Warning
Commonhouseholdcurrentis110-120volts.
Aslong as your toolis rated from 110-120V
therewillbenocomplicationsusingthistool
withhouseholdreceptacles. NEVERtryto
pluga 110-120Vtoolinto a 220-240Vcircuit
(orvice-versa)orseriouscomplicationsand
possibleseriousinjurytotheoperatorcan
occur. Theplugshavedifferentshapesto
preventthis.
Check to see if your tool has a two or three-
prongplug. Ifyourtoolhas a two-prong plug,
youmay proceed past thenext paragraph. If
yourtoolhasathree-prongplug,pleasecontinue
readingthefollowingprecautionsandinstruc-
tions.
Ifthetoolormachinehasathree-prongplug, the
third(round)prongistheground. Plugthiscord
onlyintoa three-prong receptacle. Do not
attempttodefeattheprotectionthegroundwire
providesbycuttingoffthe roundprong. Cutting
offthegroundwill resultinasafetyhazardand
voidthewarranty.
Ifathree-prongreceptacleisnotavailable,you
mayuseanadapter,butyoumustthenconnect
thegreen ear onthe adapter tothe outlet.
Unscrewthecenterscrew of the outletcover
andputthescrew through the green ear. Plug
theadapter’stwo prongs into theoutlet,and
replacethe center screw. Now plugthe tool or
machineintotheadapter.
DONOT MODIFYTHE PLUGINANY
WAY. IFYOUHAVEANYDOUBT,CALL
AQUALIFIEDELECTRICIAN.
Extension Cords
____________________________________________________________________________
Ifyourtoolis double insulated and has atwo-prongplug,youmayuse either a two orthree-prong
extensioncord. Ifyourtoolhasagrounded, three-prong plug, you must use a three-prongextension
cordwiththree-prong receptacles. Only use roundedjacketextensioncords listed by theUnder-
writersLaboratories(UL). If you are using thetooloutdoors, use an extension cordratedfor
outdooruse(signifiedby“WA”onthejacket).
Theextensioncordmusthavea minimum wiresizedependingontheamperageofthetooland the
lengthoftheextensioncord. ThesizeisdeterminedbyitsAWG(AmericanWireGauge)rating. The
smallerthegauge, the greater thecable’s capacity. The amount ofcordsused does not matter. Total
lengthdeterminestheminimumAWG rating. Every cord mustmeettheAWGrating. Usethechart
belowtodeterminewhatAWGratingisrequiredforyoursituation. Cordlengthisratedinfeet.
HarborFreightToolscansupplyULlistedandoutdoorratedextensioncordsinmultipleAWG
ratingsifneeded.
SKU #33684 Page 3
AMP TotalExtensionCordLengthInFeet
Rating 25’ 50’ 75’ 100’ 125’ 150’ 175’ 200’
0.0 -10.0 18 18 16 16 14 14 12 12
10.1-13.0 16 16 14 14 14 12 12 12
13.1-15.0 14 14 12 12 12 12 12 --
15.1-18.0 14 12 12 12 12 12 -- --

Additional Safety Rules for Mini Lathe
1. Beforeturningonthemotor,makesure
thatproperlubricationisincluded(seepage
ofthismanual).
2. Alwaysdismountthechuckandlathe’s
faceplate by hand. Do not usepower tools
toperformthese tasks.
3. Afterthechuckisinstalled,removethe
wrenchesandtoolstoeliminatethepossi-
bilityofaccident whenthelatheisturned
on.
4. Neveradjust or fixworkpieces or any
rotatingpartswhenthe lathe is on. Never
useinstrumentstomeasuretheworkpiece
whenthe lathe is on. Nevercheck the
sharpnessofthecutterbyusingyourhand.
5. Avoidaccidentsresultingfrombroken
workpieces. Neveruseanexcessively large
toolcuttertodofeedingwithalarge
workpiece.
6.Neverchangethegearwhenthelatheisin
operation.
7. Alwayskeepa safe distance fromthelathe
tominimizetherisk ofbeingstruckbya
brokenworkpiece.
____________________________________________________________________________
Thankyou forchoosinga HarborFreightTools product! Forfuturereference,please
completetheowner’s recordbelow:
Model:_______________ SerialNumber:_________________ PurchaseDate:__________
SAVETHE RECEIPT,WARRANTYANDTHESE INSTRUCTIONS. Itis important that you
readtheentiremanualtobecomefamiliarwiththeunitBEFOREyoubeginassembly.
____________________________________________________________________________
Technical Specifications
Motor: 3/4Horsepower
PowerSource: 110V, Single Phase
LatheSpecifications:
Drive: GearandBelt
SwingOverBed: 7”
DistanceBetweenCenters: 10”
SpindleBore: 3/4”
QuillTravel: 2”
CrossSlideTravel: 2 3/4”
CrossSlideSwing: 41/2”
Work Tolerance: .005”
BedDimensions: 157/8”long,31/4”wide
SaddleTravel: 6 7/8”
CompoundTravel: 27/8”
SKU #33684 Page 4

Unpacking
CarefullyunpacktheMiniLatheandcheckallitems. Figure1belowshowsallthecontentsofthe
carton. Donotdiscardanypacking materialuntiltheMiniLatheisfullyassembled andoperational.
Ifany parts aremissing or broken, please call Harbor FreightTools at 1-800-444-3353. Be sure
youhaveallpartsdescribed in the parts listing onpage .
Identification of Main Components
A. Lathe B.Chuck Key C. ExternalJaws
D. Chuck E. Chuck Set Screws F. InternalJaws
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Mini Lathe Features
1. PowerSwitch
2. Power lamp
3. Fuse
4. Speed Control Knob
6. Chuck
7. CompoundRest
8. Tool Post
9. Fixed Center
10.TailstockQuillFixHolder
11. Tailstock
12. TailstockQuillAdjustHandwheel
13. Tailstock Set Screw
14. Compound Rest Crank
1.15. FeedingControlWheel
16. Cross Feeding Crank
17. AutomaticFeedingHandle
18. ThreadDialIndicator
19. Bed Way
20. Lead Screw
21. Rear Splash Guard
22. FeedingDirectionSelector
23. Power Cord
24. ChipTray
25. Motor Cover
26. H/LGearShift Lever
27. End Cover
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Adjusting the Mini Lathe
1. Cleanofftheprotective grease on the Mini Lathe.
2. Check to see that the three set screws on the chuck are tight.
3. Turnthechuck by handandcheck that it rotatesfreely.
4. MovetheFeeding Direction Selector (locatedonthe back of lathe) tothemiddle.
5. Makesure the Switch(#1 in figure4 below) is atthe OFF position.
WARNING: ADJUSTTHE SPEEDCONTROL KNOB (#4)BY TURNINGIT TO
ZERO. BEFORE TURNINGON THE MINI LATHE EACH TIME IT ISTO BE USED,
THIS SPEED CONTROLKNOB MUST BEAT ZERO.
6. Plugintheelectricalcord and turn the Switch totheONpositionandrun the lathe for 3 minutes.
Whenthe lathe is on,thePower Lamp (#2) willremain on. Check to seethatthe lathe operates
normally.
7. Checkthe CompoundRest Crank and the CrossFeeding Crank to see that they workproperly.
Ifthe cranks are tootightor too loose, turntheadjusting screws located atboth sides (see figure5
below).
WARNING: THEMINI LATHEMUSTBECOMPLETELYSTOPPEDBEFORE
CHANGINGFORWARD/REVERSEDIRECTION.
Replacement of Chuck
Whenreplaceing the chuck,place a clothor a pieceof wood onthe bedway at thebottom of the
chuck. Thisstepwillhelpavoiddamageto the bedway caused by carelessly dropping the chuck.
To replace the chuck,loosed the 3 setscrews as showninfigure 6 below.
Rev01/99SKU #33684 Page 7

Replacement of Jaws
Therearetwotypesof jaws: the internal
jawsand external jaws. Please notethatthe
numberofjaws fitwiththenumberinsidethe
chuck’s groove. Donotmixthemtogether.
Whenyouaregoingtomountthejaws,
mounttheminascendingorder. When they
aretaken out, makesure to take them out in
descendingorder (3-2-1) one by one. After
youfinishthisprocedure,rotatethejawsto
thesmallestdiameterandcheckthatthethree
jawsarewellfitted(seefigure7).
Ifthejawsdonotfitwelltogether,youwillneedto
reassemblethemagain.
Whenmountingaworkpiece, itisrecommended
thatallthreejaws are loosened at thesametime.
Thiswillprotectthethreadsinside.
Compound Rest Adjustment
To adjust the compoundrest,loosen the two
screwsasshowninfigure8(A). Afteradjusting
totherequiredangle,tightenthescrews.
To change position or replace the tailstock, loosen thenutasshownin(A)offigure9.
Replacement of Carbon Brushes
To replace, remove brush coversonthemotor cover (A) infigure10-A,and the right bottom sideof
speedcontrollerasshownin(B)offigure 10-B.
Tailstock Rest Adjustment
SKU #33684 Page 8

Tool Post Adjustment
Loosenthelevershownin(B)offigure11,
theadjust the tool postposition. Once the
adjustmentismade,re-tightenthelever. To
replacethework cutter,loosenthe screws
(A)withtheallen wrenchprovided.
Automatic Feeding
Adjustthefeedingdirectionselectorto the
directionyoudesire. Pressdownthehandle
(A)infigure12, andcontinuewiththe
automaticfeedingprocedure. When
feeding,nevertryto changethefeeding
direction.
Threading
Selectthefeedingdirectionselectortothe
threaddirectiondesired. Thenpress down
handle(A)infigure12by matchingtheright
calibrationsonthethread dial indicator(B)
andcontinuewiththeautomaticthreading
procedure. Whenthreading,nevertry to
changethedirection.
Operation
1. Usethe chuck to hold theworkpiece
firmly(figure13below). Then,usetherolling
centertofixthe other end. If youchangethe
rollingcentertodrillingchuckyoustartyour
drillingimmediately.
2. Usethechuckto hold the workpiece firmly
andcuttertostartlathe’sfacecutting(figure
14). Theedge of the cutter must be atthe
sameheightasthecenter.
SKU #33684 Page 9

3. Bychangingthetoolpostangleandadjustingthecompoundrest,you can do internal cutting
(figure15).
4. Afteradjustingtheangleofthecompoundrest,youcandobevelcutting(figure16).
Set-Up Instructions for Threading Gears
Bychangingthegearset-upitispossibleto cut any thread size. The factory set-up for Mini Lathe
gearsisasfollows(seeillustrationbelow):
To change the thread size,usethegear box settings shownonthetable on the next page.
B
D
D
A A
C C B
PositionA=20T
PositionB=80T
PositionC=20T
PositionD=80T
SKU #33684 Page 10

Gear Settings for Various Thread Sizes
SKU #33684 Page11
Threads Stud Gear Box Threads Stud Gear Box
PerInch A B C D PerInch A B C D
12 40 30 38 20 50 60 57
13 40 65 60 30 40 20 50
14 40 35 44 20 55
16 40 40 48 20 60
18 40 45 52 20 65
19 40 50 60 57 56 20 35 30 60
20 40 50 64 20 40 20 40
22 40 55 72 20 45 20 40
24 40 60 76 20 50 30 57
26 40 65 80 20 50 20 40
28 20 35 88 20 55 20 40
32 20 40 96 20 60 20 40
36 20 45 104 20 65 20 40
Example: Tocut12threadsperinch (see illustration below), use 40TinpositionA,30Tin
positionD, and put anyothergear is position Btoconnect A and D.
A
A
B B
D D
Example: Tocut38threadsperinch(seeillustrationabove),use20Tin position
A,57T in position D,50Tinposition B, and 60Tinposition C.
B C C B
D D
AA

SKU #33684 Page 13

SKU #33684 Page 14

SKU #33684 Page 15
Parts Diagram

Additional Set-Up Instructions for Threading Gears
WhenthelatheisONandthe Spindle is revolving, the threaded bar and theThreadDialIndicator
willalsobe revolving(seebelow).
Insure thatthe Alignment Mark islined up with the
Thread Dial Indicator before operation.
Movethecuttingbladeto the proper position, and adjusttheThreadDialIndicatorto the desired
mark. PulldowntheHandle and theMiniLathestartsthreadingautomatically.
Remember: Afterthreadcuttingoperationiscomplete,changebackto the factory set-up gear
setting: PositionA=20T
PositionB=80T
PositionC=20T
PositionD=80T
#33684 Page 12
Top View
ThreadIndicatorHousing
Thread Dial Indicator
Indicator Housing
SKU #33684 Page 12

SKU #33684 Page 16

PACKINGLIST
No. Description Qty PartNo.
1 7” x10” MiniLathe 1 piece
2 Chuck externaljaws 3 piece
3 ChueckKey 1piece
4 Fuse 5A 1piece
5 Gear Z: 30, 35, 40, 40, 45, 50, 55, 57, 60, 65 10 pieces
6 Double head wrench 8-10,14-17 2pieces
7 Insidesix horn wrenchS: 3, 4,5, 6 4pieces
8 Oilcan 1 piece
9 Center MT: 2 1piece 143
10 Rubber 4 pieces 125
11 Knob 2pieces 85
12 InstructionManual 1 copy
13 WiringDiagramofControlCircuit 1 copy
14 WarrantyDocument 1 copy
SKU #33684 Page 17

SKU #33684 Page 18
Potentiometer
Switch2
Motor
Switch1
110V/60Hz
Fuse
SCHEMATIC DIAGRAM
REV08/04