• This procedure assumes that you have went through the steps before spindle centerline in the ST, DS - Field Service Lathe Level and Alignment Checklist. If not, do this now to ensure that you do not induce errors from other components that could be out of alignment.  Always start at the basics and then move forward.
• Check the current spindle centerline setting:
  • Start with tool pocket 1
  • For Hybrid turrets, first check the VDI pockets and make any necessary adjustment to bring the turrent into centerline if need be. This will assure the whole turret is in alignment.  Then you can go check each of the BOT pockets and adjust individual pockets by using the cam if necessary.
• Note: Make sure that the mating surfaces of the tooling are clean. Any debris between the turret and the toolholder will affect the measurements.
• Get the value of Parameter 254 SPINDLE CENTERLINE from SYSTEM parameters
• Instert Parameter 254 into a TOOL GEOMETRY offest that is not used
  • Press F2 to insert the Parameter 254 value.  It should now show in inches or millimeters
• Clamp the co-axial indicator [2] in the chuck
• Install a boring bar toolholder into tool 1 [1]
• Jog the turret until the co-axial indicator is inside the toolhoder
• Then carefully jog the machine to the x position that was recorded from the Parameter 254 value
• Sweep the inner diameter (ID) of the tool holder bore [1]
  • Not to Exceed (NTE) 0.001" (0.0254 mm)
• Pockets other than tool 1 must not exceed 0.003" (0.076mm)
• If this value is exceeded you will you need to adjust your spindle centerline

If you have a machine with a Y-Axis, go to procedure Lathe - Y-Axis - Toolholder to Spindle Centerline - CHC

• If you have a VDI turret without a Y-Axis you will need to move the wedge or spindle to find centerline because the toolholders are not adjustable.
• If you have a BOT turret without a Y-Axis you can adjust the toolholder by doing the following:
• If the concenticity exceeded 0.001", and you have a BOT turret without a y-axis, you use the eccentric locator cam [1] and the wedge to adjust concentricity of the toolholder to the spindle centerline as follows:
• If the indicator shows you're out in the 12 o'clock to 6 o'clock positions (up and down movement of the toolholder), then you can use the cam to move the toolholder up and down
• If the indicator shows you're out in the 3 o'clock to 9 o'clock positions, you can move the wedge fore and aft to adjust the measurement
• Loosen the cam [1] screw a small distance. This will free the cam.
  • Turn the cam with your hand to move the toolholder up or down. 
  • Turn the cam a maximum of 90 degrees clockwise to move the toolholder down. 
  • Turn the cam a maximum of 90 degrees counterclockwise to move the toolholder up. 
  • For example, if you turn the cam 15 degrees clockwise, this moves the toolholder down .0018" (0.046 mm).
  •  If you turn the cam 15 degrees counterclockwise, this moves the toolholder up .0018" (0.046 mm).
  • 15 degrees = 0.0018" (0.046 mm)
  • 30 degrees = 0.0035" (0.089 mm)
  • 45 degrees = 0.0050" (0.13 mm)
  • 60 degrees = 0.0060" (0.15 mm)
  • 75 degrees = 0.0067" (0.17 mm)
  • 90 degrees = 0.0070" (0.18 mm)
• Once set, tighten the cam and install the pocket back to the turret
• Measure the concentricity of the toolholder to spindle centerline - repeat until it doesn't exceed 0.001" (0.0254 mm)
• Once set repeat for the rest of the toolholders, NTE 0.003" (0.076 mm)

• Set the value for Parameter 254 Spindle Center, as follows.
• In DEBUG mode, press [POSIT].
• Record the COMMAND X value from the DEBUG RAW DATA.
  
  • This value is the position you adjusted the machine to in section 1

• Enter the recorded value to Parameter 254. Ignore the decimal point and the "-" sign.
  • For example, for -78.2231 enter 782231.

• Test the new value of Parameter 254 as follows. 
• Press [OFFSET] to go to the TOOL GEOMETRY offsets. 
• Go to an unused offset. Press [F2] to input the Parameter 254 value in inches. 
• Record the value in inches
  

• Jog the Z-Axis to move the turret away from the indicator.
• Zero Return the X-Axis.
• In MDI mode, program a move to X-Axis position you recorded from inserting Parameter 254 into the offset.
• Press [CYCLE START] to start the program.

• Check the measurement of the alignment of the toolholders to the spindle centerline to ensure the indicator still reads 0 in the 3 o'clock and 9 o'clock positions. 
•  If it still reads 0, then Parameter 254 has been set correctly, if not, you will need to repeat Section 2.
  
• Be sure to calibrate the tool probe at this time. Refer to the procedure in the Lathe Operator's Manual. Then you are done, Section 4 does not apply to machines without a Y-Axis.