Southbend SB1059F User Manual

Page of 140
-40-
For Machines Mfg. Since 3/11
EVS Toolroom Lathe w/DRO
O P E R A T I O N
Scroll Chuck Clamping
This scroll-type chuck has an internal scroll-gear 
that moves all jaws in unison when adjusted with 
the chuck key. This chuck will hold cylindrical 
parts on-center with the axis of spindle rotation 
and can be rotated at high speeds if the 
workpiece is properly clamped and balanced. 
Never mix jaw types or positions to 
accommodate an odd-shaped workpiece.
 
The chuck will spin out of balance and 
may throw the workpiece! Instead, use an 
independent jaw chuck or a faceplate.
Figure 35. Jaw selection and workpiece holding.
Insufficient
Jaw Clamping
Unstable
Workpiece
Bar Stock
Inside 
Safer
Use
Jaw
Cylinder
Unsafe Jaw Position
Poor Scroll
Gear Engagement
Inside 
Safer
Use
Jaw
Shallow
Bar Stock
Inside
Unsafe
Use
Jaw
Poor Scroll Gear Engagement
Unsafe Jaw Position and
Outside 
Safer
Use
Jaw
Poor Scroll Gear Engagement
Unsafe Jaw Position and
Poor
Unstable
Workpiece
Shallow
Bar Stock
Outside 
Safer
Use
Jaw
 Grip
Because of the dynamic forces involved in 
machining a non-concentric or off-center 
workpiece, always use a low spindle speed 
to reduce risk of the workpiece coming loose 
and being thrown from the lathe, which could 
cause death or serious personal injury.
4-Jaw Chuck
Refer to the Chuck Installation (see Page 38
and Chuck Removal (see Page 39) instructions  
to install or remove the 4-jaw chuck.
The 4-jaw chuck features independently 
adjustable hardened steel jaws for holding non-
concentric or off-center workpieces. Each jaw can 
be independently removed from the chuck body 
and reversed for a wide range of work holding 
versatility.
Mounting Workpiece
1.
  DISCONNECT LATHE FROM POWER!
2.
  Place a chuck cradle or plywood on the 
bedway below the chuck to protect the 
bedway surfaces.
3.
  Use the chuck key to open each jaw so the 
workpiece will lay flat against the chuck 
face, jaw steps, or into the spindle opening.
4.
  With help from another person or a holding 
device, position the workpiece so it is 
centered in the chuck.