Really not all that big, but big compared to yours 12" thru spindle and can hold about a 19" part in the chuck. Been doing this a long time and cut my teeth on little engine lathes like yours. Those machines are the backbone of America. Logans and South Bends. Monarchs and Clausings. My buddy is always bragging about his Jet and says they are really well built. The big ones a Mazak Powermaster.