Alignment and Runout Test Bars

  • Made from high quality Case hardening material
  • Used for alignment of centres and testing of machine spindles
  • Hardened and tempered to 58±2º HRC for increased wear resistance
  • precision ground throughout the length 
  • Available Shanks:
    • MT (runout within 0.005mm)
    • ISO (runout within 0.003mm)
    • HSK (runout within 0.003mm)
Alignment and Runout Test Bars


Case Hardening Steel

0.003 mm

Testing runouts and aligning centres with test bars

Machine's spindle wear can greatly impact the accuracy and the finish of the produced parts. A worn-down spindle can lead to eccentricities and out of tolerance parts and can even break or damage the clamped tools. It thus becomes essential to regularly check the health of these spindles.

Alignment test bars can be used to inspect the female taper of the lathe's spindle, spindle's parallelism to the saddle's movement and the alignment of the tailstock with the headstock. Poorly aligned centres can lead to unintentional tapers across the length of the workpiece.

A runout test arbor is used along with the dial gauge to measure any axial or radial runout transferred by the worn-down spindle of the milling machine.

Both the test bars tell us about the overall health and accuracy of the machine spindles thus preventing tool breakage, improving work finish and maintaining tight tolerances. Taper OAL Action


TB-MT1 MT1 6
TB-MT2 MT2 11
TB-MT3 MT3 13
TB-MT4 MT4 15
TB-MT5 MT5 16


TB-A50 HSK A50 8
TB-A63 HSK A63 12
TB-A100 HSK A100 12


TB-ISO30 ISO 30 12
TB-ISO40 ISO 40 12
TB-ISO50 ISO 50 12