Grinding wheels

[Don Dougan <dondougan@xxxxxxxx>]

Jane;

Sorry for the confusion about temper -- carbide has no temper.  Temper is
a term that only refers to carbon steel tools.

Think of  tungsten carbide as more like ceramic than metal.  It is always
hard but brittle.  Temper refers to the relative hardness vs. toughness
of the carbon-steel.  The harder it is the more brittle (and less tough
or durable) it is.

As  'VenezianoJ'  simply stated:  "with steel, use water.  With tungsten,
DON'T use
water"  . . . and just to be safe try not to overheat the carbide - as
Paul Rigby appears to have caught me in some overly-emphatic red-hot
hyperbole.

For what it is worth, I don't use carbide chisels very much in my own
carving (I carve lots of different marbles and softer stones).   I own
less than ten carbide-tipped tools, but I have several times that many
carbon steel chisels (many of which are solely for use in the classroom).

I like the control a nicely-tapered edge that a high-carbon steel chisel
allows me, and having to sharpen it more often is just the price I
willingly pay for the responsive 'sweetness' of the tool.
It is rarely that I let a student use one of my favorite tapered chisels
? students just don't know how to use them yet and break them too easily
? so I let them use 'classroom tools' with a relatively blunt factory
grind until they buy their own tools.  When I have accumulated about a
dozen or so broken tools I pull out the torch and files to anneal,
reshape, harden, and temper them back into working condition.  If I knew
of a willing local blacksmith I'd let him/her do all that piecework.

Of course when I do tackle a piece of granite, it IS worth using a
carbide-tipped tool (though I must also admit I sharpen them to a
more-tapered angle than the manufacturer recommends, and treat them
gently so they don't break  . . . [errrrr ? perhaps I should say they
don't break TOO OFTEN when I use them, and I don't take chances and let
anyone else borrow them]).

Sorry for rambling on, but the right chisels (and how they are kept
sharp) are important distinctions for this carver.

Good grinding to you (all in the name of carving),
Don
http://www.dondougan.com