Thread cutting on a lathe is not really needed on most projects..............quality tap and dies are the more common way and far easier shaft threading process.
It possible to get quality results with the 9x13 Jet, grizzly (sold under a dozen other names) some better than others. Most have to tuned and tweaked and have discussed in the garage many times. Some of the china stuff is real junk. Not all 9x13 come from the same place although appear to be similar quality and function vary widely.
1982 CX500 Turbo ,2006 ST1300, 2012 NC700X
1971 CT90,1981 C70, 1986 TRX 250,
1993 TRX300 4X4, 1987 XR250L