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Actually the lathe doesn't matter the tool does. Carbide seems to do very well for me and I use a skew as well but find I have to touch up the edge quite frequently.
While I would never disagree with an experienced turner, I've been turning for many years and have found that there is a difference au'contrere.
The most experienced turner still translates differing pressures to the blank beingturned....thus....and this is only MY experience, turning some things are less fraught with breakage using the metal lathe. Granted, using Carbide tools does in fact help a less experienced turner, but the amount of pressure exerted upon the tool varies from person to person. I happen to be 'heavy' handed or 'ham' handed (large hands) and over the years have broken a few blanks.
The metal lathe replaces the hands with a consistency of even pressure so long as your bites with the ML aren't too deep. Tru-stone turns like melted butter. granted a few more passes with the ML, but the time expelled is roughly equal. It might take a little more time to set up the metal lathe to do the first blank.
I am however old fashioned and anything can and should be turned by hand! On larger orders of exotics, my spouse and I set up a conveyor. She drills and glues, I use the metal lathe and she and I sand to get those orders out.....Thanks
Spalted pithy wood turns easier within limits