Friday, December 16, 2005
Helpful Information
THE KNIFE CENTER PRESENTS
A Glossary of Knife Terms
To help you in your understanding as you browse through the KnifeCenter of the Internet, we offer this glossary. It is not yet complete and will grow through time to include diagrams and pictures as well as lots more words. If there is a particular word, phrase or anything that you don't understand here, please feel free to e-mail us and we will try to explain what we can. We wish to thank Dexter Ewing for his help on this page.
I. Handle Materials
STAG derived from naturally shed deer antlers. When exposed to open flame, stag takes on that slightly burnt look. Very elegant material for pocketknives.
BONE derived from naturally deceased animals. Bone is usually given a surface texture, most commonly in the forms of pickbone and jigged bone. Bone can be dyed to achieve bright colors (e.g. green, blue, and black). This is the most common handle material for pocketknives.
G-10 a fiberglass based laminate. Layers of fiberglass cloth are soaked in resin and are compressed and baked. The resulting material is very hard, lightweight, and strong. Surface texture is added in the form of checkering. G-10 is an ideal material for tactical folders because of its ruggedness and lightweight. It is usually available in black.
MICARTA the most common form is linen micarta. Similar construction as G-10. The layers of linen cloths are soaked in a phoenolic resin. The end product is a material that is lightweight, strong, as well as having a touch of class (thus dressier than G-10). Micarta has no surface texture, it is extremely smooth to the touch. It is a material that requires hand labor, which translates into a higher priced knife. Micarta is a relatively soft material that can be scratched if not treated properly.
CARBON FIBER composed of thin strands of carbon, tightly woven in a weave pattern, that are set in resin. It is a highly futuristic looking material with a definite "ahhhh" factor. Of all the lightweight synthetic handle materials, carbon fiber is perhaps the strongest. The main visual attraction of this material is the ability of the carbon strands to reflect light, making the weave pattern highly visible. Carbon fiber is also a labor-intensive material that results in a rather pricey knife.
ZYTEL®Du Pont developed this thermoplastic material. Of all synthetic materials, ZYTEL® is the least expensive to produce, which explains the abundance of work knives that have this material. It is unbreakable: resists impact and abrasions. ZYTEL® has a slight surface texture, but knife companies using this material will add additional, more aggressive surface texture to augment this slight texture.
TITANIUM a nonferrous metal alloy, the most common form of titanium is 6AL/4V: 6% aluminum, 4% vanadium, and 90% pure titanium. This is a lightweight metal alloy that offers unsurpassed corrosion resistance of any metal. It has a warm "grip you back" feel and can be finished either by anodizing or bead blasting. Aside from handles, titanium is also used as liner materials for locking liner knives for it is a rather "springy" metal.
ALUMINUM just like titanium, aluminum is also a nonferrous metal. Commonly used as handles, aluminum gives the knife a solid feel, without the extra weight. The most common form of aluminum is T6-6061, a heat treatable grade. The most common finishing process for aluminum is anodizing.
ANODIZATION an electrochemical process which adds color to titanium, which is especially conducive to this coloring process. Depending on the voltage used, colors can vary (high voltage = dark color, low voltage = light color).
BEAD BLASTING a process by which steel, aluminum, and titanium are finished. Bead blasting is commonly found on tactical folders and fixed blades, for it provides a 100% subdued, non-glare finish.
II BLADE STEELS
1) AUS-8 (also referred to as 8A) (some text courtesy of Cold Steel, Inc.)- The words "stainless steel" are misleading, because, in fact all steel will stain or show discoloration if left in adverse conditions for a sufficient time. Steel is made "stainless" by adding Chromium and reducing its Carbon content during the smelting process.
Some authorities claim that there is a serious performance trade off with stainless steel: As the Chrome increases and the Carbon decreases, the steel be comes more "stainless". But it also becomes more and more difficult to sharpen and, some claim, the edge-holding potential is seriously impaired. We have found that most stainless steel blades are as sharp as other material blades and hold the edge longer.
AUS 8A is a high carbon, low chromium stainless steel that has proven, over time, to be a very good compromise between toughness, strength, edge holding and resistance to corrosion.
2) ATS-34 - premium grade of stainless steel used by most custom knifemakers and upper echelon factory knives. It is Japanese steel, owned by Hitachi Steels. The American made equivalent of ATS-34 is 154CM, a steel popularized by renowned maker Bob Loveless.
3) GIN-1 (formerly known as G2) - another low cost steel, but slightly softer than AUS-8.
4) CPM-T440V - sometimes touted as the "super steel", it outlasts all stainless steels on the market today. It is, however, harder to resharpen (due to its unprecedented edge retention). But the tradeoff is that you do not have to sharpen as frequently. CPM-T440V is widely used by custom knifemakers and is slowly finding its way into high-end factory knives.
5) SAN MAI III - (text courtesy of Cold Steel, Inc.) An expensive, traditional style Japanese laminate. Hard, high carbon stainless forms the core and edge of the blade, while two layers of tough, spring tempered stainless support and strengthen it. The resulting blade possesses the best qualities of both types of steel.This laminate is 25% stronger than the incredibly tough AUS 8A stainless . The telltale sign of genuine San Mai III is a thin line near the edge that runs the entire length of the blade. This line is created in the grinding process as the layers of steel in the blade are exposed. The distance the line is from the edge varies from knife to knife because every piece of San Mai III steel is unique.Like AUS 8A stainless, San Mai III is treated in modern, precise conveyor furnaces and subjected to a sub zero post hardening process. This improves the microstructure of the steel by eliminating retained austenite. The resulting blades are more elastic and have better edge holding characteristics than standard stainless steels.
6) 420J2 - (text courtesy of Cold Steel, Inc.) Due to its low carbon high chromium content this steel is an excellent choice for making tough (bends instead of breaking), shock absorbing knife blades with excel lent resistance to corrosion and moderate edge holding ability. It is an ideal candidate for knife blades that will be subject to a wide variety of environmental conditions including high temperature, humidity, and airborne corrosives such as salt in a marine environment.
This extreme resistance to corrosion via its high chrome content also makes it a perfect choice for knife blades which are carried close to the body or in a pocket and blades which will receive little or no care or maintenance
Carbon V (From Cold Steel, Inc.) - An exclusive carbon alloy steel, formulated and extensively treated to achieve exceptional properties. Carbon V was developed and refined by using both metallurgical and performance testing. Blades were subjected to the "Cold Steel Challenge" as a practical test, and then they were sectioned, so that their microstructure could be examined. In this way we arrived at the optimum steel AND the optimum heat treatment sequence to bring out the best in the steel.
Cold Steel buys large quantities of premium high carbon cutlery steel with small amounts of elemental alloys added in the smelting stage. These elements enhance the blade's performance in edge holding and elasticity. The steel is then rolled to their exact specifications to establish optimum grain refinement and blades are blanked to take full advantage of the grain direction in the steel.
The blanks are heated in molten salt, quenched in premium oil and tempered in controlled ovens. Then they are ground. The new blades are then subjected to expert heat treatment, involving rigidly controlled austenizing temperatures, precisely defined soak times, proper selection of quenching medium and carefully monitored tempering times and temperatures. This heat treatment sequence results in blades which duplicate and often exceed the properties of the most expensive custom forgings.
Premium U.S. High Carbon (from Cold Steel, Inc.)- Cold Steel's Premium Carbon Steel is used in a variety of our low cost highly functional knives. Chemical content and microstructure from the mill is specified by Cold Steel and each lot is subjected to the same metallurgical examination before being used in production as our world famous Carbon V.
The Steel is a very clean,fine grained material with a high carbon content for toughness and response to heat treatment. Cold Steel has designed a special heat treatment for this material which maximizes toughness in combination with more than acceptable edge holding ability, resulting in a blade which will satisfy even the most discriminating user.
III LOCKING MECHANISMS
1) LOCKING LINER - this particular locking system was refined by knifemaker Michael Walker. The actual locking mechanism is incorporated in the liner of the handle, hence the name. If there is a metal sheet inside the handle material, it is called a liner.
With a locking liner, opening the blade will allow this metal will flex over and butt against the base of the blade inside the handle, locking it open. Moving this liner aside will release this lock allowing the blade to close. Disengagement of the lock is performed with the thumb, allowing for one handed, hassle free action. Locking liners are commonly found on tactical folders, both production and custom.
2) LOCKBACK - this style of lock has a spring-loaded locking bar with a tooth at the end. The tooth falls into the notch cut into the blade tang and is held there under the spring tension. A cut out in the handle spine houses the release for the lock. These locks generally require 2 hands to unlock and close.
IV BLADE GRINDS
1) HOLLOW GRIND the most common grind, found on the majority of custom and production pieces. Hollow ground blades have a thin edge that continues upwards, and is the grind is produced on both sides of the blade. Since the cutting edge is relatively thin, there is very little drag when cutting.
Examples of knives with hollow ground blades: Spyderco Howard Viele C42 and Kershaw Ti-ATS-34.
2) FLAT GRIND Flat grinds are characterized by the tapering of the blade from the spine down to the cutting edge. This style of grind is also referred to as a "V" grind, since the cross section of this grind resembles that letter. The chisel grind, a popular style for tactical blades, is a variation of the flat grind. On a chisel round blade, it is ground on one side, and on the other it is not.
These blades are easier to sharpen, because you sharpen one side only. Example of a knife with a chisel ground blade would be the Benchmade 970 Ernest Emerson CQC7. Examples of knives with a flat grind are the Benchmade Mel Pardue 850 and Spyderco's C36 Military model.
3) CONCAVE GRIND Similar to the flat grind in that the blade tapers from the spine to the cutting edge, except the taper lines are arcs instead of straight lines.
4) CONVEX GRIND Similar to the flat grind in that the blade tapers from the spine to the cutting edge, except the taper lines are arcs extending outward instead of inward as in the convex grind above or straight lines. If you picture a pumpkin seed, you will get a good idea of what the cross sectional view of this grind is like. Noted custom knife maker Bill Moran is credited for bringing the convex grind into the focus of knife making.
A Glossary of Knife Terms
To help you in your understanding as you browse through the KnifeCenter of the Internet, we offer this glossary. It is not yet complete and will grow through time to include diagrams and pictures as well as lots more words. If there is a particular word, phrase or anything that you don't understand here, please feel free to e-mail us and we will try to explain what we can. We wish to thank Dexter Ewing for his help on this page.
I. Handle Materials
STAG derived from naturally shed deer antlers. When exposed to open flame, stag takes on that slightly burnt look. Very elegant material for pocketknives.
BONE derived from naturally deceased animals. Bone is usually given a surface texture, most commonly in the forms of pickbone and jigged bone. Bone can be dyed to achieve bright colors (e.g. green, blue, and black). This is the most common handle material for pocketknives.
G-10 a fiberglass based laminate. Layers of fiberglass cloth are soaked in resin and are compressed and baked. The resulting material is very hard, lightweight, and strong. Surface texture is added in the form of checkering. G-10 is an ideal material for tactical folders because of its ruggedness and lightweight. It is usually available in black.
MICARTA the most common form is linen micarta. Similar construction as G-10. The layers of linen cloths are soaked in a phoenolic resin. The end product is a material that is lightweight, strong, as well as having a touch of class (thus dressier than G-10). Micarta has no surface texture, it is extremely smooth to the touch. It is a material that requires hand labor, which translates into a higher priced knife. Micarta is a relatively soft material that can be scratched if not treated properly.
CARBON FIBER composed of thin strands of carbon, tightly woven in a weave pattern, that are set in resin. It is a highly futuristic looking material with a definite "ahhhh" factor. Of all the lightweight synthetic handle materials, carbon fiber is perhaps the strongest. The main visual attraction of this material is the ability of the carbon strands to reflect light, making the weave pattern highly visible. Carbon fiber is also a labor-intensive material that results in a rather pricey knife.
ZYTEL®Du Pont developed this thermoplastic material. Of all synthetic materials, ZYTEL® is the least expensive to produce, which explains the abundance of work knives that have this material. It is unbreakable: resists impact and abrasions. ZYTEL® has a slight surface texture, but knife companies using this material will add additional, more aggressive surface texture to augment this slight texture.
TITANIUM a nonferrous metal alloy, the most common form of titanium is 6AL/4V: 6% aluminum, 4% vanadium, and 90% pure titanium. This is a lightweight metal alloy that offers unsurpassed corrosion resistance of any metal. It has a warm "grip you back" feel and can be finished either by anodizing or bead blasting. Aside from handles, titanium is also used as liner materials for locking liner knives for it is a rather "springy" metal.
ALUMINUM just like titanium, aluminum is also a nonferrous metal. Commonly used as handles, aluminum gives the knife a solid feel, without the extra weight. The most common form of aluminum is T6-6061, a heat treatable grade. The most common finishing process for aluminum is anodizing.
ANODIZATION an electrochemical process which adds color to titanium, which is especially conducive to this coloring process. Depending on the voltage used, colors can vary (high voltage = dark color, low voltage = light color).
BEAD BLASTING a process by which steel, aluminum, and titanium are finished. Bead blasting is commonly found on tactical folders and fixed blades, for it provides a 100% subdued, non-glare finish.
II BLADE STEELS
1) AUS-8 (also referred to as 8A) (some text courtesy of Cold Steel, Inc.)- The words "stainless steel" are misleading, because, in fact all steel will stain or show discoloration if left in adverse conditions for a sufficient time. Steel is made "stainless" by adding Chromium and reducing its Carbon content during the smelting process.
Some authorities claim that there is a serious performance trade off with stainless steel: As the Chrome increases and the Carbon decreases, the steel be comes more "stainless". But it also becomes more and more difficult to sharpen and, some claim, the edge-holding potential is seriously impaired. We have found that most stainless steel blades are as sharp as other material blades and hold the edge longer.
AUS 8A is a high carbon, low chromium stainless steel that has proven, over time, to be a very good compromise between toughness, strength, edge holding and resistance to corrosion.
2) ATS-34 - premium grade of stainless steel used by most custom knifemakers and upper echelon factory knives. It is Japanese steel, owned by Hitachi Steels. The American made equivalent of ATS-34 is 154CM, a steel popularized by renowned maker Bob Loveless.
3) GIN-1 (formerly known as G2) - another low cost steel, but slightly softer than AUS-8.
4) CPM-T440V - sometimes touted as the "super steel", it outlasts all stainless steels on the market today. It is, however, harder to resharpen (due to its unprecedented edge retention). But the tradeoff is that you do not have to sharpen as frequently. CPM-T440V is widely used by custom knifemakers and is slowly finding its way into high-end factory knives.
5) SAN MAI III - (text courtesy of Cold Steel, Inc.) An expensive, traditional style Japanese laminate. Hard, high carbon stainless forms the core and edge of the blade, while two layers of tough, spring tempered stainless support and strengthen it. The resulting blade possesses the best qualities of both types of steel.This laminate is 25% stronger than the incredibly tough AUS 8A stainless . The telltale sign of genuine San Mai III is a thin line near the edge that runs the entire length of the blade. This line is created in the grinding process as the layers of steel in the blade are exposed. The distance the line is from the edge varies from knife to knife because every piece of San Mai III steel is unique.Like AUS 8A stainless, San Mai III is treated in modern, precise conveyor furnaces and subjected to a sub zero post hardening process. This improves the microstructure of the steel by eliminating retained austenite. The resulting blades are more elastic and have better edge holding characteristics than standard stainless steels.
6) 420J2 - (text courtesy of Cold Steel, Inc.) Due to its low carbon high chromium content this steel is an excellent choice for making tough (bends instead of breaking), shock absorbing knife blades with excel lent resistance to corrosion and moderate edge holding ability. It is an ideal candidate for knife blades that will be subject to a wide variety of environmental conditions including high temperature, humidity, and airborne corrosives such as salt in a marine environment.
This extreme resistance to corrosion via its high chrome content also makes it a perfect choice for knife blades which are carried close to the body or in a pocket and blades which will receive little or no care or maintenance
Carbon V (From Cold Steel, Inc.) - An exclusive carbon alloy steel, formulated and extensively treated to achieve exceptional properties. Carbon V was developed and refined by using both metallurgical and performance testing. Blades were subjected to the "Cold Steel Challenge" as a practical test, and then they were sectioned, so that their microstructure could be examined. In this way we arrived at the optimum steel AND the optimum heat treatment sequence to bring out the best in the steel.
Cold Steel buys large quantities of premium high carbon cutlery steel with small amounts of elemental alloys added in the smelting stage. These elements enhance the blade's performance in edge holding and elasticity. The steel is then rolled to their exact specifications to establish optimum grain refinement and blades are blanked to take full advantage of the grain direction in the steel.
The blanks are heated in molten salt, quenched in premium oil and tempered in controlled ovens. Then they are ground. The new blades are then subjected to expert heat treatment, involving rigidly controlled austenizing temperatures, precisely defined soak times, proper selection of quenching medium and carefully monitored tempering times and temperatures. This heat treatment sequence results in blades which duplicate and often exceed the properties of the most expensive custom forgings.
Premium U.S. High Carbon (from Cold Steel, Inc.)- Cold Steel's Premium Carbon Steel is used in a variety of our low cost highly functional knives. Chemical content and microstructure from the mill is specified by Cold Steel and each lot is subjected to the same metallurgical examination before being used in production as our world famous Carbon V.
The Steel is a very clean,fine grained material with a high carbon content for toughness and response to heat treatment. Cold Steel has designed a special heat treatment for this material which maximizes toughness in combination with more than acceptable edge holding ability, resulting in a blade which will satisfy even the most discriminating user.
III LOCKING MECHANISMS
1) LOCKING LINER - this particular locking system was refined by knifemaker Michael Walker. The actual locking mechanism is incorporated in the liner of the handle, hence the name. If there is a metal sheet inside the handle material, it is called a liner.
With a locking liner, opening the blade will allow this metal will flex over and butt against the base of the blade inside the handle, locking it open. Moving this liner aside will release this lock allowing the blade to close. Disengagement of the lock is performed with the thumb, allowing for one handed, hassle free action. Locking liners are commonly found on tactical folders, both production and custom.
2) LOCKBACK - this style of lock has a spring-loaded locking bar with a tooth at the end. The tooth falls into the notch cut into the blade tang and is held there under the spring tension. A cut out in the handle spine houses the release for the lock. These locks generally require 2 hands to unlock and close.
IV BLADE GRINDS
1) HOLLOW GRIND the most common grind, found on the majority of custom and production pieces. Hollow ground blades have a thin edge that continues upwards, and is the grind is produced on both sides of the blade. Since the cutting edge is relatively thin, there is very little drag when cutting.
Examples of knives with hollow ground blades: Spyderco Howard Viele C42 and Kershaw Ti-ATS-34.
2) FLAT GRIND Flat grinds are characterized by the tapering of the blade from the spine down to the cutting edge. This style of grind is also referred to as a "V" grind, since the cross section of this grind resembles that letter. The chisel grind, a popular style for tactical blades, is a variation of the flat grind. On a chisel round blade, it is ground on one side, and on the other it is not.
These blades are easier to sharpen, because you sharpen one side only. Example of a knife with a chisel ground blade would be the Benchmade 970 Ernest Emerson CQC7. Examples of knives with a flat grind are the Benchmade Mel Pardue 850 and Spyderco's C36 Military model.
3) CONCAVE GRIND Similar to the flat grind in that the blade tapers from the spine to the cutting edge, except the taper lines are arcs instead of straight lines.
4) CONVEX GRIND Similar to the flat grind in that the blade tapers from the spine to the cutting edge, except the taper lines are arcs extending outward instead of inward as in the convex grind above or straight lines. If you picture a pumpkin seed, you will get a good idea of what the cross sectional view of this grind is like. Noted custom knife maker Bill Moran is credited for bringing the convex grind into the focus of knife making.
