How to Hold Concentricity in Turning: Core and Tube Methods

Why Concentricity Matters

Poor concentricity between mating diameters causes runout, uneven wear and noise in assemblies.

Main Causes

• Second setup: Different location datum when flipping (most common)
• Worn chuck jaws
• Excessive overhang, low rigidity
• Bent stock

Control

• Single setup: Machine critical diameters in one chucking
• Soft jaws: Bore jaws in place for true concentric grip
• Face/bore location: Use machined datum when flipping
• Steady rest: For slender parts
• Straighten stock first

Inspection

Runout gauge with dial indicator; track trends in sampling. Huami fully inspects core and tube critical sizes.