Rob....

I would just find yourself a stepped shank set of drill bits. They are readily available, either that or get a larger drill chuck for your tailstock. Another option is to make a drill bit adapter, basically machine yourself a piece that fits in the tailstock chuck with a larger face that you can drill into with whatever drill bit you intend to use using the headstock chuck. Then just drill and tap it for a couple setscrews to keep it from spinning. There is ALWAYS more than one way... Another option is to use a boring bit and offset your tailstock to attain the desired diameter if your lathe has that feature. Good luck and peace

Pete



Pete Matos

Safe Journey Space Fans, Wherever you are....