There are certain requirements for this lathe which I consider absolute, and many other optional possibilities. Together, these for the Design Guidelines. So lets go through a few.
I want to be able to turn down the seat for the crown-race of the steerer. This requires a spindle bore of at least 1.25 inches, and preferably one of 1.5 inches. In fact, I think that most older salvage headstocks from US machines will be light in the spindle bore. So there is a good chance that I will need to manufacture my spindle, or subcontract the construction of same.
I have looked at the cost of asian replacement spindles, and they arent' cheap when one gets above the 7x12s. Moreover, I'm not sure the quality is there. I need to get some more current ANSI lathe specs, but comparing a 1945 set of ANSI specs with claims of a better regarded asian clone wasn't impressive (for the clone).
My intended bed is Expox/Aggregate. Shouldn't be hard to get good results at home - particularly with a little planning.
The motor would be a vaiable speed drive w/belt dryive to the spindle to help isoate vibrations. I want the final machine to be smooth running an ridgid.
Ifigure this to be a nominal 10.5" x 30". but to have actual clearance of 13" on the swing. For my purposes, 2 hp should be sufficient, but rigidity should sufficient to handle a5hp motor.
Given the CNC advantages, even if he manual modes, I expect to sue NC functiosn. So, for exmple, no compound which adds weight, height, complexity, cost, soure of error.
Finally, let me close by noting that I'm in hospital with a staph infection. So if there are egregious mis-spellings, or poor sentences, Please do let that throw you off, we'll all be speeked thsame soon.