Measuring an internal taper using two balls

In this video I bore a 3.25º taper in a piece of aluminum and measured the taper and the diameter of the mouth opening using two ball bearings that I bought at a hardware store. Check out Joe PI's youtube page:    • Measuring Chamfers and conical features on...   Check out Outside Screwballs Dykem Sucks rant :    • Dykem Sucks.... Rant