http://www.woodreview.com.au 39TOOLS & EQUIPMENTA2 was considered to be a big
advancement over O1 because it is
much harder and holds an edge for
longer. But I’ve found there are some
issues with A2 steel, the major one
being that the edge shatters as it
wears and you can just see this with
the naked eye, or more readily with
a magnifying glass. You might think
that this is because of the harder
woods that we use in Australia but
the same effect is seen with European
and North American woods.
The fix is to sharpen A2 steel at 35°
instead of the more usual 30°. This
works for most bench chisels and
for bevel down planes. However for
paring chisels and bevel up planes
you do want to be able to use lower
cutting angles of 25-30°.
A2 chisels and blades are available
from Lie-Nielsen, Veritas, Blue
Spruce and other high end suppliers.
Replacement A2 blades are also
available for older Stanley and
Record planes. For chisels expect to
pay $80 – $100.
High speed steel (HSS)
These steels have additional elements
like tungsten, vanadium, cobalt or
molybdenum which allow the hardened
steel to resist softening at very high
6 7
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working temperatures. They are called
high speed steel for their ability to
run at high speed, for example when
cutting metal. The extra hardness also
makes HSS more difficult to sharpen
although modern composite water
stones do so without too much trouble.
In woodworking, HSS is most often
found in lathe tools which are usually
sharpened on a grinding wheel. HNT
Gordon also offers HSS blades for their
hand planes.Powder metals (PMV)
Powder metal technology has been
around for a long time but a morerecent development has been the
addition of alloys such as vanadium.
Vanadium carbide particles are
very small and wear resistant
but vanadium tends to fall out of
suspension as molten steel cools.To solve this problem high vanadium
steel is sprayed through a very small
nozzle into a vacuum chamber to
cool into a fine powder. This powder
can now be compressed and rolled
into sheets like any other steel. The
resultant product is incredibly fine
grained highly wear resistant steel
that will take a keen edge and hold it.