Well, all you say is quite true....I'm coming from the armchair engineer of old angle and am a veritable newcomer to CNC machining with a degree from the school of KISS....…….although I have a CNC mill it's not for production and mainly from the learning side.....oldies need their toys to keep their marbles clicking.
I'll stick with the simple 3 jaw chuck option as I think it will suffice for what I intend to do.
BTW....with all that servo drive and coupling in line with the 4th spindle, where can you fit a powered draw tube for the 5C.....by my reckoning you won't get much bar length if the servo is directly in line behind the 4th...…..would it not be a better option to drive from the side with an offset and a timing belt etc?...….. much as I dislike timing belt drives.
Even then I cannot imagine a longish bar of steel, say 20mm diam, sticking unsupported out of the 4th spindle end and revolving at a couple of thousand rpm with a turning operation...…...turret lathes have a bar feeder to feed and steady the long bar outside of the spindle.
Ian.