You may be experiencing run-out if any part of the lathe or drill press wobbles or vibrates while spinning. 

This is usually caused by parts of the lathe/drill press or accessories not being concentric with the spindle axis of rotation. Follow this guide to identify and measure lathe or drill press runout. 

You will need a Dial Test Indicator (DTI) with a stand to test for runout. Follow the FAQ guide attached below for step-by-step instructions on how to test your lathe for runout.