Over twenty eight years ago I aquired an extra Burnerd Chuck for my Hercus it became surplus as I have five Chucks for the metal lathe, cut an adapter to fit the Hercus threat outside and 1 inch 10 threads inside did not like the knuckle buster chuck jaws made a front cover to fit over the jaws held in place by a washer and pressure on the Mandrel. My mandrel was made using a machine bolt and my design Mandrel saver from a removable centre live centre with a parrallel shaft with a close fit to the mandrel.
Some guy in America got in touch asked if I wanted to go in with him making versions of my Mandrel Saver I declined sent him measurements etc.Use a collet chuck and another type of mandrel saver I designed and had made in hard steel.
Peter.
