Definition
A hand tool with a sharpened cutting edge on the end of a metal shank, used to cut, shape, or remove material such as metal, wood, or stone. In aircraft maintenance, chisels are commonly used to cut sheet metal, shear off damaged rivet heads, or split seized fasteners.
Plain English
A tool with a sharp edge that you strike with a hammer to cut or chip away material. Mechanics use them mostly to cut metal or remove old rivets.
Context Anchor
Seen in aircraft maintenance, sheet metal work, woodworking, and general shop-tool descriptions.
Derivation
From the Old French 'cisel,' meaning a cutting tool, which traces back to the Latin 'caedere,' meaning to cut. The origin reinforces that a chisel is fundamentally a cutting instrument, not a prying or shaping one.
Why Pilots Care
Pilots who own or maintain their own aircraft, or who supervise maintenance, should recognize when a chisel is the correct tool versus when its use could damage surrounding structure. A chisel used carelessly on a rivet can deform the surrounding skin and create costly repairs.
Intuition Check
Do not think of a chisel as just any sharp tool. In shop use, it is a specific cutting tool with a shaped edge, often driven by hand pressure or hammer blows.
Example Sentence 1
The mechanic used a sharp chisel to shear off the head of the damaged rivet before drilling it out.
Example Sentence 2
During preflight inspection follow-up, a chisel was used to split the corroded nut on the engine mount bolt.