Answer :
Final answer:
To align lathe centers using a dial indicator and a test bar, the plunger of the dial indicator should be set parallel to the axis of rotation. The plunger should be properly adjusted and seated against the test bar. The lathe centers can then be adjusted based on the readings of the dial indicator.
Explanation:
To align lathe centers using a dial indicator and a test bar, the plunger of the dial indicator should be set parallel to the axis of rotation. This ensures that the indicator accurately measures any variation in alignment between the centers.
When setting the plunger, it is important to make sure it is properly adjusted and seated against the test bar. This can be done by gently tapping the plunger until it is snugly in place.
Once the plunger is set, the lathe centers can be adjusted by moving either the tailstock or headstock until the dial indicator reads zero or within the acceptable tolerance range.