"Ted Edwards" wrote in message
...
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

Ted and I have been at odds on occasion, and this is likely one of the
subjects that could easily be debated between us. In retrospect, I'd like
to say that what Ted says is pretty much on target. When I clear my mind
from my years of commercial machining, I think the only fair statement I
would make regards using carbide on light duty machines is that you are not
realizing the full capability of the carbide, simply because it is capable
of so much more than the machine can provide. On a minor note, carbide
can perform at a lower level when not run at proper speeds, but it would be
highly unlikely that the average guy would recognize the difference.
Often, even in the commercial shops, only when running a production job
repeatedly do you start realizing that certain choices of carbide and
different speeds and feeds make a difference. Based on that, I'm
inclined to fully agree with Ted. Carbide inserts can be useful on small
machines.

The one negative is that many substitute the learning curve of hand grinding
toolbits, so they are for ever handicapped in that regard. I strongly
recommend one learn to grind high speed toolbits, no matter the equipment at
hand, unless running CNC, where hand ground tools are not necessarily in
anyone's best interest under production situations, anyway.

Harold