Awesome will have to get a hold on a couple of old chucks!
Reno, Paul

"Gunner" wrote in message
news
On Sat, 31 Jan 2004 13:40:23 -0800, "Paul"
wrote:

The tool length that we are using is about 3 inches so they do tend to
heat
up. Either way...so If I'm dunking my cutting tool every time it gets too
hot to hold... I'm pressing too hard or is this proper technique?
Perhaps
this is just something the teacher is
having us to "before" getting to using HSS. He did however show us using
a
torch
what quenching a cold rolled steel does to the strength. Smacking it with
a
hammer
while it was held in a vice snapped it right in two. However before
mistreating it
with water and the torch it would bend waaaaaay before breaking.

Paul


Ill tell you a trick that really helps when freehand grinding HSS and
for grinding bolts off to length on a grinder or band saw.

Grab a drill chuck, clamp it down on your bit or bolt and use it as a
handle.

Ive dog robbed a number of old drill motor chucks and keep one at every
belt sander and grinding station in my humble shop just for this
purpose. This is a good use for those old chucks that are worn and run
out.

btw...cold rolled steel is NOT HSS. It doesnt have much carbon in it.
Hss starts out harder than the best hardening you can do to a chunk of
crs.

Gunner



"Gary Coffman" wrote in message
.. .
On Sat, 31 Jan 2004 17:43:14 GMT, steamer wrote:
--Do it the way the teacher says until you're comfortable with the
process. Nothing wrong with using the tool rest; safer, too, for a
newbie.
I still use it faithfully. The only time I *don't* use a tool rest is
when
I'm sharpening a drillbit. As for quenching: don't let the tool get
hot
enough to change color B4 you quench and you won't have the annealing
problem. Dunk the tool B4 you start grinding; when the last of the
liquid
boils off dunk it again, etc.

Quenching won't anneal anything. Quenching hardens heat treatable
steel.

HSS is used for tool bits because it doesn't lose its strength at a red
heat. It won't lose its strength at a red heat when grinding either.
But
the very edge in contact with the wheel gets to yellow heat (note the
color of the sparks), and dipping it in water will cause microcracks at
the edge which will weaken it.

You wouldn't quench an oil or air hardening steel in water, because
it would crack. Don't do it with HSS bits you're grinding either, for
the
same reason. The water pot on a bench grinder is the devil's invention,
don't use it. If the bit gets too hot to handle while grinding, set it
down for a minute, and don't press so hard next time.

Gary


Liberals - Cosmopolitan critics, men who are the friends
of every country save their own. Benjamin Disraeli