Lathe spindle construction Lathe spindles are commonly made hollow and provided with which feature for accurate location of centers, arbors, and tooling?

Introduction / Context:
Machine tool spindles must locate accessories precisely and transmit torque safely. In engine lathes, the headstock spindle is typically hollow to pass bar stock and to accept standard tooling.

Given Data / Assumptions:

• Typical workshop/engine lathe.
• Use of centers, taper shank drills, arbors, and live centers.

Concept / Approach:
An internal self-holding taper (commonly Morse taper) inside the spindle nose ensures accurate, repeatable alignment for taper-shank tools and centers. The hollow spindle also allows long bars to pass through for production convenience.

Step-by-Step Solution:

Verification / Alternative check:
Manufacturer specifications for engine lathes list Morse taper numbers (e.g., MT4, MT5) for the headstock spindle.

Why Other Options Are Wrong:
External tapers are used on noses, sleeves, or tooling—not as the primary locating feature inside the spindle bore. A straight bore cannot firmly seat taper shanks without adapters.

Common Pitfalls:
Confusing spindle nose mounting standards (e.g., Camlock, A, L types) with the internal Morse taper; both can coexist for different purposes.

Final Answer:

Internal taper