There are a variety of knife blade shapes; some
of the most common are listed below.
1. A normal or straightback blade has a curving edge, and flat back. A
dull back lets the wielder use fingers to concentrate force; it also makes the
knife heavy and strong for its size. The curve concentrates force on a small
point, making cutting easier. This knife can chop as well as pick and slice.
2. A curved, trailing-point knife has a back edge that curves upward.
This lets a lightweight knife have a larger curve on its edge. Such a knife is
optimized for slicing or slashing. Trailing point blades provide a larger
cutting area, or belly, and are common on skinning knives.
3. A clip-point blade is like a normal blade with the back "clipped" or
concavely formed to make the tip thinner and sharper. The back edge of the clip
may have a false edge that could be sharpened to make a second edge. The sharp
tip is useful as a pick, or for cutting in tight places. If the false edge is
sharpened it increases the knife's effectiveness in piercing. The Bowie knife
has a clipped blade and clip-points are quite common on pocket knives and other
4. A drop-point blade has a convex curve of the back towards the point.
It handles much like the clip-point through with a stronger point less suitable
for piercing. Swiss army pocket knives often have drop-points on their larger
5. A spear-point blade is a symmetrical blade with a spine that runs
along the middle of the blade. The point is in line with the spine. Spear-points
may be single-edged (with a false edge) or double-edged or may have only a
portion of the second edge sharpened. Pen-knives are often single-edged, non-spined
spear-points, usually quite small, named for their past use in sharpening quills
for writing. Pen-knife may also nowadays refer to somewhat larger pockets knives
which are often drop-points. Some throwing knives may have spear-points but
without the spine, being only flat pieces of metal.
6. A needle-point blade is a symmetrical, highly tapered, twin-edged
blade often seen in fighting blades, such as the Fairbairn-Sykes commando knife.
Its long, narrow point offers good penetration but is liable to breakage if
abused. Although often referred to as a knife, this design may also be referred
to as a stiletto or (slender variety of) dagger due to its use as a stabbing
weapon albeit one very capable of slashing as well.
7. A spay-point (once used for spaying animals) has a single, mostly
straight edge that curves strongly upwards at the end to meet a short, dull,
straight clip from the dull back. With the curved end of the blade being closer
to perpendicular to the blade's axis than other knives and lacking a point,
making penetration unlikely, spay points can be suitable for skinning.
8. A Westernised tanto style knife has a somewhat chisel-like point that
is thick towards the point (being close to the spine) and is thus quite strong.
It is superficially similar to the points on most Japanese long and short swords
( katana and wakizashi ). The traditional Japanese tanto knife uses the blade
geometry of (1). The Westernised tanto is often straight but may also be gently
curved. The point is actually a second edge on the end of the blade, with a
total edge angle of 60 – 80 degrees. Some varieties may have the back edge
angled to the point slightly and sharpened for a short distance from the point.
9. A sheepsfoot knife has a straight edge and a straight dull back that
curves towards the edge at the end. It gives the most control, because the dull
back edge is made to be held by fingers. Sheepsfoot knives are good for
whittling and trimming sheep's hooves.
10. A Wharncliffe blade is similar in profile to a sheep's foot but the
curve of the back edge starts closer to the handle and is more gradual. Its
blade is much thicker than a knife of comparable size.
11. and 12. An ulu (Inuit woman's knife) knife is a sharpened segment of
a circle. This blade type has no point, and has a handle in the middle. It is
good for scraping, and sometimes chopping. It is the strongest knife shape. The
semi-circular version appears elsewhere in the world and is called a head knife.
It is used in leatherworking both to scrape down leather (reducing thickness),
and to make precise, rolling cuts for shapes other than straight lines.