Three attachments: Ball Contact, Disc Contact and Wiggler Shank
Ball diameter 0.250" or 6.3 mm
Disc contact: small disc at the end (0.100"/2.5 mm) diameter.
Wiggler shank is 0.375" diameter.
Starrett Wiggler Center Finder.
Starrett catalog number S828.
The wiggler center finder and three different attachments adapt to countless applications and are readily interchangeable. The attachments are snapped in the chuck without removing the collet nut and are clamped by a ball swivel-joint, which permits adjustment to an angular position or true concentricity.
With the pointed shank, working centers can be quickly and accurately located. Spring tension on the ball of the point permits guiding the point to true concentricity so that the work can be brought into perfect alignment with the machine spindle.
The ball contact is useful in locating work by first bringing the contact (ball diameter 0.250" or 6.3 mm) against the work, a slot, hole, shoulder, or end, and indexing the work to the desired position relative to the spindle.
The disc contact, which has a small disc at the end (0.100"/2.5 mm) diameter, permits use in more confined areas such as slots or shallow holes.
The wiggler shank is 0.375" diameter.
Chris' Tips How does this gadget work? What are those different attachments for? See How to Use a Wiggler.Here is how to use a wiggler.