This flat and elongated part of knife, weapon, tool or a machine component is usually finished with a point. Blade is commonly used for chopping, slicing, cutting and other kinds of machining tasks.
The most common examples are:
-
blade as a part of weapon – sword, sabre, spade, halberd, sword, rapier, dagger;
-
blade as a part of tool – knife, axe, machete, scissors, saw, scythe, razor;
-
blade as a part of machinery – scissors, medical scalpel, lawn mower, machine tools.
Types of knife blades
Based on the blade edge, we identify following types of knife blades: single edge only have one cutting edge (this can be found on most types of knives), or double edge with two cutting edges (spear point or needle point blades).
Depending on the blade, we distinguish between straight, serrated and combined blades. Serrated blades improve the knife's ability to cut and rip solid and fibrous materials – smoothly and yet more aggressively without jerking. This type of blade is designed e.g. for cutting belts, ropes, seat belts and clothing – often to be found on rescue knives.
As for materials, we've got metal and non-metal blades. Besides cutler steels (either stainless or other), there are other commonly used materials such as metal or iron alloys, Grivory plastic or ceramic. These alternative materials are becoming increasingly popular. Back in the ancient times, our ancestors used to work with blades which were made from bronze or flint.
What are the different blade shapes?
-
Normal Blade/Straight Back Blade: a single edge with curved edge and straight spine. This type of blade is rather typical for a kitchen use than outdoor types of knives - yet, there are some exceptions. Long spine makes the knife heavy and sturdy, suitable for chopping and slicing. Users can easily guide the knife and apply additional pressure on the blunt spine.
-
Drop-Point Blade: a single edge with convex spine that curves down in the direction from the handle to the point. Often to be seen on larger types of Swiss Army knives.
-
Clip-Point Blade: another single edge, however, this time the front section of the spine is clipped off. The sharp point with low profile is suitable for cutting in narrow spaces. The cut-off can be either straight or concave. There can be a false blade in this section which can get sharpened when necessary and serve as an additional blade – perfect for stabbing and penetrating. The knife point is much closer to the centre of the blade. This offers you more control when stabbing. This blade can be found on the classic Bowie combat knife. It is also typical for folding knives.
-
Tanto Blade: the term tanto refers to the Japanese word of tanto, although in reality this has little in common with those knives. This blade is single-edged, blade and spine are straight. The point is situated either on the level of the spine or a little lower. The spine slopes towards the point, similarly to the Clip-Point. At the front, the blade is inclined at different angles – which is called chisel point. The undeniable advantage of this blade is the thickness which is even along the entire length – from the handle almost to the point. According to test, penetration ability of tanto is not very high, but using a force, it can penetrate without causing a damage to the point.
-
Spear-Point Blade: this blade is symmetrical along the longitudinal axis. The point is in line with the centre of the knife. The correct Spear-Point Blade has a central spine and can have two sharp edges, just like a dagger or a spear head. This is one of the strongest blades designed for stabbing – therefore, we can find it on many types of stabbing knives. The term Spear-Point is sometimes incorrectly used for small knives built into a pen or pocket multitools (small blades for small activities such as opening envelopes or packages). However, such blades do not have a central spine and two cutting edges and are more of the Drop-Point or Clip-Point.
-
Sheepsfoot Blade: a straight single cutting edge and a blunt spine which curves down to meet the point, seated on the bottom side – at the level of the blade. This blade gives the user full control over the knife while the spine is curved to give a support to the fingers. It was originally developed to trim the sheep hooves – therefore, its shape does not refer to the shape of a sheep's foot, as the name might suggest.
-
Wharncliffe Blade: a single-edged blade similar to the Sheepsfoot Blade. The spine curve is slower and begins noticeably closer to the handle. Compared to the knives/blades of the same size, the Wharncliffe is much thicker. These knives were used by sailors – the shape of the point prevented accidental penetration of a material or hand injuries caused by a sudden move of the ship.
-
Trailing-Point Blade: single-edged, similar to the Straight-Back, but the blade rises upwards - above the level of the spine. This curve can be of different lengths and it can rise to different levels above the back. The whole blade or a significant part of it can be curved. This blade is good for slicing, skinning and chopping. Blunt spine allows the user to lead the knife well and concentrate the force, the rounded blade cuts perfectly. This blade can be found on hunting knives. The curve of the blade forms the so-called belly, ideal for processing the game.
-
Needle-Point Blade: the blae is sharply tapering towards a symmetrical point. We can find it on daggers such as Stiletto stab dagger (it has no blade). The long and narrow point reduces friction and increases vigorous penetrating abilities, but it tends to get stuck in a bone and it can break when mishandled.
-
Spey-Point Blade: a single-edged blade originally designed to neuter domestic animals. The blade is curved and rises in the front, meeting a short blunt at the point which is coming from a flat spine. This knife is good for opening packages without risking a damage of the content or removing the fur without risking accidental puncture. Therefore, this blade can be found on trappers' knives.
-
Leaf Blade: this single-edged blade really does resemble a leaf shape. The narrow blade gradually widens behind the handle and then narrows again towards the point. The spear point is axially symmetrical (like the Spear-Point Blade) and the point is in line with the longitudinal axis. This knife is good for cutting and chopping. The centre of gravity is a bit forward, which makes the Leaf Blade an ideal throwing knife.
-
Hawkbill Blade: a single-edged blade is sharpened on the inner side. A knife with this kind of blade is similar to carpet or linoleum knives. The point of the blae will tear even when the rest of the blade is relatively blunt. The Southeast Asian version of this knife is called Karambit which can be sharpened on both inner and outer side. This makes Karambit a combat knife for both normal and reverse grip.
So-called Flame Blade is rather used for decorative knives, collector pieces or swords. This blade in the shape of a flame has significant curvatures and tapers towards the point. Usually double-edged.
Ulu is a knife formed by a sharpened segment of a circle. This type of blade has no point and has a handle in the middle. Suitable for scraping and sometimes chopping. The semicircular version is called the Headknife and is used e.g. for processing the leather (when reducing its thickness or making precise and curved cuts). The circular version is popular for slicing pizza. Folding ulu knives can also be found.
The curved blade of Kukri is also specific. As a symbol of Nepali Gurkhas – warriors of the British Empire - Kukri has been a traditional weapon for several centuries. The single-edged blade is bent downwards and is sharp on the inner side. It widens in the front part and narrows again towards the point. This blade is known for its ability to concentrate the destructive force in the front and feared for its ability to amputate the limbs of the game or an enemy with a single cut. Blades of this type can be found on machetes (e.g. the Ka-bar 1249), fixed-blade knives (e.g. Ka-bar BK4) and even folding knives (e.g. Rajah Cold Steel).