I purchased a new set of nylon ring holding jaws for our Vigor inside ring engraver. Easy enough to install, but then the stylus was not perfectly centered to the middle of the ring. Nothing on-line about how to readjust the stylus. The one place seeming to be an adjustment is on the back at the top; an allan head set screw with a 1/2" lock nut. I loosened the lock nut and played with the adjustment until the stylus was centered. I re-tightened the lock nut and began engraving a ring. Immediately I noticed the adjustment was erratic and that there were four tiny balls covered with bearing grease had fallen out of the mechanism between the two light bulbs. Can some one explain what I’ve done here?