There is a plethora of misunderstanding with TBC.
As Don Wrote:
Turning between centers can be done with special TBC bushings or with standard bushings.
[/QUOTE]
And you do not necessarily have to use a 60° drive center either, but it depends on the bushing one has.
TBC got its great push to popularity here on IAP in 2007 although it was used by a few in other places.
TBC works best for most people by using the bushings FOR Turning to Size, then taking the bushings OFF for the Finishing Process.
Advantages:
1. much faster to take a blank off and inspect it and replace it and turn again than to take a mandrel off, take the nut off and a spacer or two, then replace, screw the nut back on and add it to the lathe.
2. TBC - No problem with having bent mandrels
3. TBC - No problem with pulling the tail stock too tight and causing mandrel flex.
4. IF you use CA as a finish or other finish for that matter, breaking the bushing from the blank, especially for oily blanks like ebonies and a few other woods that are oily, when breaking the bushing off, the CA will lift up off of the just finished blank on the end. It will look smokey, or cloudy as a result. THAT is the reason TBC was first used here.
With TBC - take the bushings OFF before finishing. You will get CA on the dead drive center, but it is so much easer to take the CA finished blank off if it does not have bushings during the finishing process!
Simple compared to mandrels!