Definition
A wooden or composite block, shaped to the contour of an aircraft structure, used to support a part during forming, fitting, or repair. The block is notched or 'toothed' so it grips the workpiece and holds it steady while the technician shapes, drills, or fastens adjacent material.
Plain English
A shaped support block with notches cut into it, used in the shop to hold an aircraft part firmly in place while a technician works on it.
Context Anchor
Seen in aircraft maintenance when inspecting or adjusting cable clamps and cable-control assemblies.
Derivation
Called a 'tooth block' because the notches cut into the block resemble teeth, and those notches are what give the block its grip on the part being worked.
Why Pilots Care
If a tooth block is worn, loose, or installed incorrectly, the cable it is supposed to hold may slip, which can affect the movement of a control or other cable-operated part.
Intuition Check
Do not read “tooth” here as a gear tooth. A tooth block is a serrated gripping piece that holds a cable, not a rotating gear part.
Example Sentence 1
The technician clamped the leading edge skin against a tooth block before drilling the rivet holes.
Example Sentence 2
Excessive play in the tooth block allowed unwanted movement between the blades and the hub assembly.