Knife making wiki
Knife making glossary
The words knife makers use, explained in a sentence or two. Terms in blue on wiki pages link here.
A
- Annealing
- Heating steel and cooling it very slowly so it is as soft as possible, ready for cutting, drilling or filing.
B
- Belly
- The curved part of the edge between the straight section and the point. It is what lets a knife rock or slice.
- Bevel
- A ground slope on the blade. The primary bevel thins the blade; the edge bevel (or secondary bevel) forms the cutting edge.
- Billet
- A bar of steel ready to be forged into a blade. In Damascus work, the welded stack of layers.
- Bolster
- A thick metal collar where the blade meets the handle, common on kitchen knives. It adds weight and protects the handle.
- Burr
- A thin wire of metal that folds over to the far side of the edge when you sharpen. Raising and then removing it is how you know you have sharpened right to the edge.
C
- Choil
- A small unsharpened notch at the back of the edge, next to the handle. It makes sharpening the whole edge easier.
- Cladding
- Softer steel forge-welded around a harder core, as in san mai. It protects the core and makes the blade tougher.
- Clip point
- A point where the spine is cut away ("clipped") near the tip, straight or concave, making a sharper, lower point. Typical of the bowie knife.
- Convex grind
- A grind whose faces curve outwards to the edge, like an axe. Strong and slices well, but harder to sharpen evenly.
D
- Decarb
- Short for decarburisation: carbon lost from the surface of hot steel, leaving a soft skin that has to be ground off.
- Drop point
- A point where the spine curves gently down to meet the edge, giving a strong tip that sits slightly below the spine.
E
- Edge retention
- How long a blade stays sharp in use. It depends on the steel, its hardness and the edge geometry.
- Etching
- Using a mild acid, such as ferric chloride, to darken steel and reveal the pattern in Damascus or a hamon.
F
- Flat grind
- A grind where both faces of the blade slope in straight lines from the spine (or near it) to the edge.
- Flux
- A powder such as borax, put on hot steel before forge welding to keep scale from forming between the layers.
- Forge welding
- Joining pieces of steel by heating them close to melting and hammering or pressing them together.
- Full tang
- A tang that is the full length and width of the handle, with the handle scales fixed to each side.
- Fuller
- A groove along the flat of a blade. It lightens and stiffens the blade; it is not a "blood groove".
G
- G10
- A laminate of glass fibre cloth and epoxy resin. Very tough, light and waterproof; a common modern handle material.
- Grit
- The size of the abrasive particles in a sharpening stone or belt. Lower numbers are coarser; higher numbers are finer.
- Guard
- A crossbar or plate between blade and handle that stops the hand sliding onto the edge.
H
- Hamon
- The visible line on a differentially hardened blade, where the hard edge meets the softer spine.
- Heel
- The end of the edge nearest the handle, often the widest and strongest part on a kitchen knife.
- Hollow grind
- A grind with concave faces, made on a grinding wheel. Very thin behind the edge, so it cuts well.
- HRC
- Rockwell C hardness, the scale used for knife steel. Most knives are between 56 and 62 HRC.
M
- Micarta
- A laminate of linen, canvas or paper layers set in resin under heat and pressure. Warm, grippy and waterproof; a classic handle material. Strictly a trade name.
N
- Normalising
- Heating steel above its critical temperature and letting it cool in still air, to refine the grain after forging.
P
- Patina
- The grey, blue or brown oxide layer that builds up on carbon steel with use. It helps slow rust.
- Pattern welding
- Forge welding layers of different steels into one billet, then forging and etching it to show a pattern. Modern Damascus.
- Plunge line
- The line where the bevel stops and the full thickness of the blade begins, near the handle.
Q
- Quench
- Cooling hot steel quickly, usually in oil, to harden it.
R
- Rat-tail tang
- A thin rod-like tang, sometimes welded on, that runs into the handle. Usually the weakest type.
- Ricasso
- A short flat, unsharpened section of the blade just in front of the guard or handle.
S
- Scales
- The two handle slabs fixed to either side of a full tang with pins, rivets or screws.
- Scandi grind
- A single wide bevel on each side that runs straight to the edge, with no secondary bevel. Common on bushcraft knives.
- Spine
- The back of the blade, opposite the edge.
- Stabilised wood
- Wood that has been vacuum-impregnated with resin and cured, so it no longer swells, shrinks or cracks with moisture.
- Stock removal
- Making a knife by cutting and grinding it from a bar of steel, rather than forging it.
- Strop
- A strip of leather or other material, often loaded with a fine compound, used to polish and straighten an edge after sharpening.
T
- Tang
- The part of the blade that runs into the handle.
- Tanto point
- An angular point where the edge turns up sharply near the tip, making a strong, thick point. Popularised on modern tactical knives.
- Tempering
- Reheating hardened steel to a lower temperature to make it less brittle. Done after the quench.
- Toughness
- A steel's resistance to chipping and breaking. Usually traded off against hardness and edge retention.
W
- Wootz
- Crucible steel made in India and Sri Lanka from ancient times. Forged and etched, it shows the pattern of historic Damascus blades.