Randal O'Brian wrote:

made from HSS cutoff blades. Carbide inserts are the only way to go on the
lathe if your machine has sufficient rigidity and power.

As usual, I'll jump in on this statement. If you have sufficient
rigidity and power to take heavy cuts at high speed, carbide inserts are
the way to go when standard shapes will do. The converse as stated
above is false. I use carbide inserts for most of my turning and am
quite pleased with the results. This is on a Smithy 3-in-1. While I
quite like the machine and can get it to do what I want, it certainly
does not have a great deal of either rigidity or power.

http://www.metalwebnews.com/howto/toolholder/toolholder.html
http://www.metalworking.com/DropBox/Prop_speed_reducer.pdf

Ted