"bob" wrote: (clip) Anyone with experience doing this? (clip)
^^^^^^^^^^^^
I am a woodturner, not a machinist, so I will tell you what little I know:
1.) You can sometimes help with tearout by waxing the wood, treating it
with lacquer sanding sealer, or thin C/A glue.
2.) You need to use very sharp tools.
3.) Woodturning practice is to turn the wood fast to get better surface
finish. I don't think this is applicable to turning threads in a metal
lathe. So the suggestion to use a router mounted on the carriage would
likely be the best way to go. There are woodturning tools designed to work
this way--it seems to me that a machine lathe would do this easily.