Lathe Ball Turning Attachment Turn Ball Up-To 38 MM Diameter For Lathes/ Radius. Ball Turning Attachment For Lathe Machine- Metalworking Tools. This fits straight onto the cross slide of your lathe machine for Quick Turning of Cones and Balls. Comes with a 1 Indexable TNMG16 Insert for best turning finish and results.Maximum Ball Diameter possible is 38 mm. The Head can be adjusted for different Ball Sizes.