I do not know of any lathe that resumes running after engaging the mechanical brake
.
Wellll.. are you confusing "brake" with a "spindle lock"? They can be separate. y'know.
And at least until "electricity" was discovered? They ALL "resumed"!
Presuming one RELEASED or "feathered" it!
Waterwheel and lineshaft thing.. but not-only.
And they remained that way for plenty of electrically-powered lathes that had/have constant running motors, mechanical CLUTCH as well as BRAKE, and even mechanical reversing. Often on the same mechanical ONLY lever, not electrical switch:
REV [Brake-Neutral] FWD.
And we PREFER it that way. And even
replicate it with "creep" rather than "jog" for easy positioning of our workholding.
Even in CNC to high degrees of positioning accuracy that are part of the spindle's routine Day Job, often every cycle.
Even a basic Parker-SSD? Exactly ONE potentiometer:
REV (and how fast) <- BRAKE/IDLE -> FWD (and how fast)
No relays. Configuration options, rather.
VFD have configuration options, too.
Plenty of them!
E-Stop?? A relatively "new thing", as machine-tools go.
And exactly what it says it is.
EMERGENCY Stop.
AND NOT a normal operating control. A different animal entirely, IOW.
Spindle lock CAN be yet-another animal. Or integrated.
Why would one confuse these distinctly identifiable functions, even where one MIGHT choose to correlate, even integrate?
Or not.
You should get around ...more than just the one or two lathes? It can be educational. Even fun.
ADDING E-Stop is nearly always a good idea.
Screwing-up a(ny) machine tool's designed flow of operation philosophy may NOT be a good idea. Think it through. Plan and review. If it doesn't suit? Fix it so it does do.
Tailor your controls to suit the OPERATOR according to the need. The flexibility is THERE. And already paid-for. So use it.
The rest is up to your preferences as to how you
NEED it to work.