Bryan, there is not a lot of travel on my Lathe's cross-slide. In fact it seems to be less than 12" so the swing over the bed may be, in practical terms, a lie.
If you think about it, if you can swing a twelve inch job, in theory the cross slide only needs to have six inches of travel.
My own lathe is an American made LeBlond manufactured in 1949. Fifteen inch swing, five foot bed, and eight inches of cross slide travel. Its rather old (like me) and I have owned it for about half of its lifetime.
It originally came from a trade school, so suffered much wear and abuse in its early days.
It was a fairly top end lathe in its day, with a geared head, and mulitichange gearbox (including metric) for screw cutting.
Its now fairly worn out, but its still possible to do accurate work with a bit of patience.
Its greatest shortcoming is the spindle bore is tiny, only inch and a half. Recently I discovered the LeBlond family are still in business and still making lathes, now have an internet site, and can supply any part of any lathe they have made over the last almost one hundred years, which is pretty amazing.
They only need the serial number of the lathe and they can supply any replacement part for it.
I am not so sure a 3d printing can ever replace a real lathe. Most often here, its a case of quickly modifying an existing part in some way, rather than fabricating something new totally from scratch.
I have recently bought a Chinese dovetail milling machine with a geared head, similar to what Americans know as a "Grizzly". Its certainly no Bridgeport machine, but its as far as my budget would reasonably extend.
A knee mill has the advantage that the cutter is always at a convenient height and easy to see. For small jobs the knee is raised. For big jobs like an engine block, the knee is lowered, but you are always working at a convenient height with the cutter.
With a dovetail mill, the slides are fixed and the head goes up and down. I am tall, and working on small jobs I really need to be sitting down or almost on my hands and knees to see what I am doing.
With a bulky job, being seven feet tall would be a definite advantage with this type of machine.....
I am in the process of fitting power feeds to three axis, and a digital readout. The power feeds use large stepper motors, and I just have one magic power box that plugs into whichever axis I want to go by itself.
One interesting feature is, I have fitted two separate DRO scales for the Z axis. One on the head, and another on the quill. These go to a digital combiner box of my own design to the digital readout, so I can adjust either the head height or the quill without losing my zero. All this is still a project in progress, but I am now probably about half way there.
All really fascinating stuff to play with.