cnc lathe project

Hello all,
I want to build a small cnc lathe with a 6 jaw chuck so I can work plastics.
From what I've seen lathe chucks have 4 joint types, cam lock, threaded nut and taper, screw on chuck ( like south bend ) and some imported chucks that bolt on the back.
The spindle looks like it would be the hardest part to come by, because the chuck interface joint looks difficult to manufacture.
I like the cam lock type - is it easy to make? Is it a good choice?
Are there adapters to go from one joint type to another or are you stuck with what you select for a joint type?
What's the best approach to getting a spindle for the lathe; should I attempt to make a spindle, or would it make more sense to buy one if I could find a source for it?
thanks
Denis