Southbend SB1231 User manual

Chucks are heavy! Get assistance when
installing or removing the chuck from the
lathe. Wear heavy duty leather boots for
foot and toe protection, and keep hands and
fingers away from all pinch points. Ignoring
this warning can lead to a severe crushing
injury or finger amputation!
Specifications
•OD Clamping...... 0.69"–10.04" (17.5–255mm)
•ID Clamping.......... 3.74"–10.83" (95–275mm)
•Chuck Bore Diameter ................2.56" (65mm)
•Chuck Outer Diameter ..........11.81" (300mm)
•Maximum Speed ...........................2500 RPM*
•Mounting Type ......................... D1-8 Camlock
• Construction..................Fine-GrainCast-Iron
• ChuckWeight......................................... 80lbs
• ChuckShippingWeight......................... 85lbs
•Country of Origin ................................ Taiwan
* ThemaximumspeedlistedaboveisONLY
possiblewiththechuckjawsandthe
workpieceincompleterotationalsymmetry.
Theworkpieceweightmustbewithinthe
limitsofthelathe,andtheworkpiecemass
mustbeofequaldensitythroughoutto
preventcentrifugalimbalanceorradial
runout—evenifatailstockorothersupport
isusedforadditionalsupport.
Instruction Sheet
PHONE: [phone] • www.southbendlathe.com
MODEL SB1231
12" 4-JAW INDEPENDENT CHUCK
Copyright © October, 2010 by South Bend Lathe Co.
WARNING: No portion of this manual may be reproduced without written approval.
#CR13310 Printed in Taiwan
Figure 1. Features.
Introduction
TheModelSB1231usesadirectmountD1-8
camlocksystemwherethecamlockstudsare
directlythreadedintotothechuckbodyinstead
of being threaded into a backing plate that
isboltedtothechuck.Withoutusingaback
platetomountthechuck,thechuckjawsare
positionedclosertotheheadstockwhichgives
alongerdistancebetweenthejawsandthe
tailstock.Anotherbenefitisthatthedistance
betweenthejawsandtheoutboardspindlenose
isreduced,soifaspidersupportisusedonthe
outboardspindle,shortgunbarrelsandother
shorterworkpiecescanbeheldatbothends.
Manufactured
with high-tech
German CNC
machinery
Fine-grain cast
iron body
Hardened steel jaws
for durability and
extreme clamping
force and grip
Independent jaw
screws for each
reversible jaw
Direct
camlock
spindle
mounting
Jaw screw
retaining pin
with lock screws

Safety
•Chuck Key Safety:Achuckkeyleftinthe
chuckcanbecomeadangerousprojectile
whenthespindleisstarted.Alwaysremove
thechuckkeyafterusingit.Developahabit
of not taking your hand off of a chuck key
unlessitisawayfromthemachine.
•Disconnect Power: Disconnectthelathe
frompowerbeforeinstallingandremoving
the chuck or doing any maintenance or
adjustments.Accidentallathestartupcan
causesevereinjuryordeath.
•Secure Clamping: Athrownworkpiece
maycausesevereinjuryorevendeath.
Whenswappingthechuckjawpositions,
keep in mind that maximum gripping
forceisattainedatfulljawandjawscrew
engagement. Ifonlyoneispartiallyengaged,
overallclampingforceisreduced.
•Speed Rates: Operating the lathe where
maximumchuckspeedisexceeded,orattoo
highofaspeedforanunbalancedworkpiece,
cancausetheworkpiecetobethrownfrom
thechuck.Alwaysusetheappropriatefeed
andspeedrates.Athrownworkpiecemay
causesevereinjuryorevendeath.
•Large Chucks: Largechucksareveryheavy
anddifficulttograsp,whichcanleadto
crushedfingersorhandsifmishandled.
Getassistancewheninstallingorremoving
largechuckstoreducethisrisk.Protectyour
handsandtheprecisiongroundwaysby
usingachuckcradleorpieceofplywoodover
thewaysofthelathewhenservicingchucks.
•Safe Clearances: Oftenchuckjawswill
protrudepastthediameterofthechuckand
cancontactacoolantnozzle,tooling,tool
post,orsaddle.Beforestartingthespindle,
makesuretheworkpieceandchuckjaws
haveadequateclearancebyrotatingthenby
handthroughitsentirerangeofmotionby
hand.
•Stopping Lathe By Hand: Stopping the
spindlebyputtingyourhandonthe
workpieceorchuckcreatesanextremerisk
ofentanglement,impact,crushing,friction,
orcuttinghazards.Neverattempttoslow
orstopthelathechuckbyusingyourhand.
Allowthespindletocometoastoponits
ownorusethebrake(ifequipped).
•Long Stock Safety: Longstockcanwhip
violentlyifnotproperlysupported,causing
seriousimpactinjuryanddamagetothe
lathe.Reducethisriskbysupportingany
stockthatextendsfromthechuck/headstock
morethanthreetimesitsowndiameter.
Alwaysturnlongstockatslowspeeds.
-2-
Mfg.Since5/10
Model SB1231 INSTRUCTIONS

Camlock Stud Installation
Thecamlockstudsthatareshippedwiththis
chuckmaybepre-installedfromthefactory.
IfsoskipthissectionandcompleteChuck
Installation and Removal on Page 4;
otherwise,installthecamlockstudsasoutlined
below:
1. Oilandthreadeachcamstudintothechuck
untilthealignmentgrooveisushwiththe
chucksurface,asshowninFigure 2.
2. Installandtightenthelockingcapscrew
foreachstud,makingsurethatthecamlock
studscanslightlyrotatebackandforth.
Figure 2. Camlock stud installation.
Figure 3. Camlock stud adjustment.
Camlock Stud Adjustment
Ifthecamlockstudshavebeenpre-installedat
thefactory,orifyouareinstallingthemforthe
rsttime,slightmachiningdifferencesbetween
thelathespindleandchuckcancauseoneor
morecamlockstolockattheincorrectlocation.
If any cam line stopsoutsideofa “V” mark when
allofthecamlockshavebeentightened, remove
thechuckandadjusttheheightoftheoffending
stud one full turn up or down asillustrated
below.Afterallcamlocksoperatecorrectly,
stampalignmentmarksinthechuckandspindle
toensurethatthechuckcanbere-installedin
thesamepositionafterbeingremoved.
Camlock Stud
Must Slightly
Rotate Back/Forth
Cap Screw
Installed & Tight
Initial Adjustment:
Camlock Stud Alignment
Groove is Flush with Chuck
Surface
Alignment Marks
Spindle Line
CORRECT
The Camlock Mark
Stops Between the
“V” Marks.
To Correct:
Turn Stud One Turn In
To Correct:
Turn Stud One Turn Out
INCORRECT
The Camlock Mark
Stops Before the
“V” Marks.
INCORRECT
The Camlock Mark
Stops After the
“V” Marks.
Mfg.Since5/10 Model SB1231
-3-
INSTRUCTIONS

6. Withthehelpofanotherperson,orwiththe
helpofachuckcradle,alignthechuckwith
thespindlesothestudsandcamlockbores
arealignedcorrectly,andcarefullyslidethe
chuckontothelathespindle.Neverrestthe
chuckonitslowerstuds,asshowninFigure
5,androllorpushthetopofthechuckinto
placeonthespindle.Thisisabadpractice
thatmaydamagethestudsandcamlock
bores.
Do not install the chuck without having
the camlock cap screws in place or fully
tightened. Otherwise, the camlock studs may
turn with the camlocks on release, resulting in
the chuck being permanently locked onto the
spindle.
Figure 5. Typical alignment of studs and camlock
bores.
3. Cleanawaydebrisandoilysubstancesfrom
thematingsurfacesofthespindleandthe
chucktoensurethebestfitpossible.
4. Inspectandmakesurethatallcamlock
studsareundamaged,clean,andlightly
oiled.
5. Makesurethatthecamlockstudretaining
capscrewsaresnug,butstillallowthestuds
toberotatedbackandforthslightlybyhand.
Thisfree-playiscriticaltoensurethatthe
camlockstightenandlockwiththestuds
completely,andwillreleasewithoutbinding.
—Ifaproblemisfoundwiththecamlock
lockingorrelease,removetheoffending
studandcleanitwithmineralspirits.
Compareitwithagoodstudforany
inconsistencies,andreplaceitifaproblem
isfound.Inspectthebore,capscrew,seat
depth,andthreadswithothersthatare
knowntobecorrect.Chaseallthreads,
andremoveanyburrsordingsintheseat.
Dryouttheborewithcompressedairand
lightly re-lubricate with a drop or two of
machine oil or way oil.
Figure 4.Wooden chuck support cradle.
Before turning the lathe
ON, make sure the chuck
key is removed! A thrown
chuck key can cause
serious injury or death to
the operator or bystanders.
1. DISCONNECTLATHEFROMPOWER!
2. Layachuckcradle(seeFigure 4) or
plywoodunderthechuckandoverthe
bedwaytoprotecttheprecisionground
surfacesfromdamageandreducetheriskof
fingersgettingpinched.
Chuck Installation and Removal
INCORRECTCORRECT
-4-
Mfg.Since5/10
Model SB1231 INSTRUCTIONS

7.  Tightencamlocksinastarpatterntodraw
thechuckinevenlyandreducethechance
ofmisalignment.Makesuretotighten
camlocksinanincrementalmannerto
ensurethatonecamlockdoesnotgetfully
tightenedbeforetheothers(i.e.,snugthe
camlocksonthefirstpass,thenmoderately
tightenonthenextpass,thenfullytighten
onthethirdpass).
 Asyoutightenthecamlocks,thechuck
willseatwiththespindlenose.Whenfully
tightened,thecamlinewillfallbetweenthe
two"V"marksonthespindlenose,asshown
in Figure 6.
Figure 6. Camlock is fully tightened with the camlock
line positioned between the "V" marks.
— Ifthecamisfullytightened,butthecam
line ispositionedoutsideofthe“V”marks,
removethechuckandadjusttheheightof
the offending camlock stud,asoutlinedin
Camlock Stud Adjustment on Page 3.
8. Wheninstallationiscompleteandyouare
satisedwiththeresults,lightlystampaset
ofalignmentmarksonthechuckandspindle.
Note: Alignmentmarksensurethatthe
chuckcanbere-installedinthecorrect
positioneverytimeforconsistentchuckand
spindlealignment.Italsoallowsforthesame
camlocksandstudstooperatetogetherfor
consistentlockingandunlocking.
Cam line is between
the "V" marks
PINCH HAZARD! Protect your hands and the
precision ground bedways with plywood or a
chuck cradle when removing the lathe chuck!
The heavy weight of a falling chuck can cause
serious injury.
To remove the chuck:
1. DISCONNECTLATHEFROMPOWER!
2. Layachuckcradleorplywoodunderthe
chuckandoverthebedwaytoprotectthe
precisiongroundsurfacesfromdamageand
reducetheriskoffingersgettingpinched.
3. Loosenthecamlocksbyturningthekey
counterclockwiseapproximatelyone-thirdof
aturnuntilthemarkonthecamlockaligns
withthespindlemarkonthespindlenose
(seeFigure 7).Ifthestuddoesnotfreely
releasefromthecamlock,wigglethecamlock
untilitstudreleases.
Note:Camlockscanbecomeverytight.Acheater
pipemaybeusedtoaddleveragewhen
loosening.
Figure 7. Camlock is fully loosened when the camlock
line is aligned with the spindle mark.
Cam line is
aligned with the
spindle mark
Mfg.Since5/10 Model SB1231
-5-
INSTRUCTIONS

CAUTION: During the next step, the
chuck may come off suddenly, so it
is important that you are ready to
support its weight with a chuck cradle
to prevent crushing your fingers or
dropping the chuck.
4. Usingadeadblowhammerorother
softmallet,lightlytaparoundtheouter
circumference of the chuck body to break the
chuckfreefromthecamlocksandthespindle
nosetaper.
5. Usearockingmotiontocarefullyremovethe
chuckfromthespindle.
—Ifthechuckdoesnotimmediatelycome
off,rotatethechuckapproximately60˚
andtapagain.Makesureallthemarks
onthecamsandspindleareinproper
alignmentforremoval.
Operation
Non-cylindricalpartscanbeheldandbrought
intothespindlecenterlineforfacingorboring
Theotherbenetisthatthemajorityof
workpiecescanbepositionedoutofthespindle
rotationaxisifabore(seeFigure 9)orastep
needstobecutintoaworkpieceonanoutlying
edge.Forthebestgrippossibleonodd-shaped
workpieces,oneormorejawscanalsoberotated
180°tograbmoresurfaceareaforclamping.
Ifallfourjawscannotbeusedtoholdthe
workpiece,youmustusefaceplatetoreducethe
riskofaworkpiecebeingthrown.
To clamp a workpiece in the chuck:
1. DISCONNECTLATHEFROMPOWER!
2. Installacenterinthetailstock.
3. Retracteachjawand place the workpiece
flatagainstthechuckface.
4. Slidethetailstockforward,sothetipofthe
deadcenterappliesenoughpressureagainst
theworkpiecetoholditinplace,andthen
lockthetailstockinposition.
5. Moveeachjawuntilitmakeslightcontact
with the workpiece.
Figure 8. Tightening sequence.
7.  Aftertheworkpieceisheldinplaceby
thejaws,turnthechuckbyhandandpay
attention to the workpiece alignment.
—Iftheworkpieceisnotcorrectlyaligned
foryouroperation,turnthechuckand
makefineadjustmentsbyslightly
looseningonejawandtighteningthe
opposingjawuntiltheworkpieceis
correctlyaligned(seeFigure 9 for an
example).
1
2
3
4
Hole to be
bored into
workpiece
Figure 9. Non-concentric workpiece correctly clamped
in the 4-jaw chuck.
6. FollowingthesequenceshowninFigure 8,
tighteneachjawinsmallincrementstomove
theworkpieceintotherequiredposition.
Checkfrequentlytomakesuretheintended
centerpointoftheworkpiecehasnot
wanderedawayfromthespindlecenterline
whilethejawsarebeingtightened.
-6-
Mfg.Since5/10
Model SB1231 INSTRUCTIONS

Jaw screw retaining pin
Set screw
a
Figure 10. Chuck sequence of disassembly.
Care & Maintenance
Always disconnect
machine from power before
performing maintenance or
serious personal injury may
result.
!
b. Backthejawsoutofthechuck
c. Removethefoursetscrews.
d. Putonsafetyglasses,anduseahammer
 anddriftpunchtotapouteachjawscrew
retaining pin.
e. Slidethejawscrewsoutoftheirbores.
4. Usingmineralspirits,cleananddryall
parts.Inspectandxallbores,teeth,pins,
andmatingsurfacesforwear,burrs,galling,
rust,orcracks.
5. Withoutchangingthedimensionofanypart,
useawirebrush,emerycloth,ordressing
stonestoremoveallrust,burrs,oranyhigh
spotscausedbygalling.
6. CoatallpartswithanyautomotiveNLGI#2
grease,andcarefullyre-assemblethechuck
inthereverseordershowninFigure 10.
7.  Rotatethechuckkeyclockwiseuntilthe
leadthreadofeachjawscrewisseenjust
enteringthejawguide,theninserteach
numberedjawintoitsnumberedslot.
8. Oneatatime,holdeachjawagainstitsjaw
screw,androtatethechuckkeyclockwiseto
engagethejawscrewwiththejaw,thenfully
threadthejawintothechuck.
9. Alignandre-installthechuck.
Foroptimumperformancefromyourchuck,
followthemaintenanceschedulebelow.Never
hammeronthechuck,jaws,oraworkpiecethat
isclampedinthechuck;andneversubjectthe
chucktoabrasives,ame,orwater.
Daily:
• Check/correctloosemountingbolts.
•Keep the chuck clean and oiled.
•Useavacuum,rag,orbrushtocleanthe
chuckafteruse. Neveruseairpressureto
cleanchipsawayfromachuck.
• Avoidleavingthechuckclampedona
workpiece,unloadthechuckjawsdaily.
• Makesurethechuckkeyisremovedfrom
thechuckwhennotinuse.
Ifthechuckeverbecomesstifftooperate,
itmayhavebeencontaminatedwithmetal
chipsorabrasivesfromincorrectorinfrequent
maintenanceintervals.Ifthisisthecase,the
chuckmustbedisassembled,cleaned,andre-
lubricated.
To disassemble the chuck for a full cleaning
and lubrication service:
1. DISCONNECTLATHEFROMPOWER!
2. Verifythatchuckalignmentmarksare
presentsothechuckcanbere-installedin
thesameposition,andremovethechuck.
Stampthemarksiftheydonotexist.
3. Leavingthecamlockstudsinplace,
disassemblethechuckinthesequencelisted
belowandshowninFigure 10.
a. Placeasetofwoodenblocksunderthe
 chucksothecamlockstudsdonotreston
 thetable,andclampthechucktothe
 tableasshowninFigure 10.
b
c
d
e
d
Mfg.Since5/10 Model SB1231
-7-
INSTRUCTIONS

Troubleshooting
Symptom Possible Cause Possible Solution
Thechuckhas
hardspotsorbinds
completely.
1. Jawisinapoorpositionfor
clamping.
1. Re-installjawsformaximumengagementwithjaw
slotandjawscrew.
2. Lackoflubrication,rust,burr,or
metalshavingsinsideofchuck.
2. Disassemble,de-burr,clean,andlubricatechuck.
3. Brokentoothonthejaworthejaw
screw.
3. Disassemblechuckandrepair/replacebrokenpart.
Theworkpieceslips
inthejaws.
1. Incorrectjaworworkpiececlamping
position.
1. Re-installjawsformaximumengagementwithjaw
slotandjawscrew.
2. Chuckisbindingbeforefull
clampingforceisachieved,orajaw
orjawscrewisbinding.
2. Chuckisloadedupwithcontaminants.Disassemble
andservicechuck.Loosenandretightenthechuck
keyseveraltimestodistributelubricant.
3. Cuttingoverload. 3. Reduce cutting depth or feed rate.
Clamping accuracy
ispoor.
1. Workpieceimproperlyclampedor
workpieceismisaligned.
1. Removejaws,clean,de-burr,andre-install;verify
accuracyandrecalibratetest/dialindicator.
2. Chuckloose;mountingisoff-center,
orisimproperlyseated.
2. Removechuck,cleanandde-burrmounting;adjust
camlockstuds,andre-installchuck.
Parts List
Please Note: We included this parts breakdown for service purposes only. Since many of the parts shown are machined to
each individual chuck, they may not be available as replacement items.
Parts Diagram
REF PART # DESCRIPTION
1 PSB1231001 REVERSIBLE CHUCK JAW
2 PSB1231002 CHUCK BODY
3 PSB1231003 JAW SCREW
4 PSB1231004 JAW SCREW PIN
5 PSS02 SET SCREW 5/16-18 X 3/8
6 PSB1231006 CHUCK KEY
7 PSB1231007 D1-8 CAMLOCK STUD
8 PCAP09 CAP SCREW 5/16-18 x 5/8
6
3
2
1
5
8
7
4
If you need help with your new chuck,
contact us at:
PHONE: [phone]
FAX: [phone] (International)
FAX: [phone] (USA Only)
EMAIL: [email protected]
-8-
Mfg.Since5/10
Model SB1231 INSTRUCTIONS