Definition
The allowable variation from a specified dimension shown on an engineering drawing or blueprint. Print tolerance defines the maximum and minimum acceptable measurements a manufactured part may have while still meeting the design requirements.
Plain English
How much a finished part is allowed to differ from the exact size shown on the drawing and still be considered acceptable.
Context Anchor
Seen when reading aircraft drawings, checking part dimensions, or deciding whether a fabricated or repaired part matches the drawing closely enough.
Derivation
Print refers to a blueprint or engineering drawing (originally printed on blue paper). Tolerance comes from the Latin tolerare, meaning to bear or allow. Together: the amount of variation the drawing allows.
Why Pilots Care
Parts made or repaired outside print tolerance may not fit, may fail under load, or may be rejected during inspection. For maintenance personnel, working within print tolerance is the difference between an airworthy part and a scrap one.
Analogy
If a board is supposed to be cut to 10 inches, but the plan allows it to be 1/16 inch longer or shorter, that allowed range is the tolerance. Print tolerance is the same idea applied to an aircraft drawing.
Intuition Check
Print does not mean the quality of ink on paper here; it means the aircraft drawing or blueprint. Tolerance does not mean patience; it means the allowed amount of variation from the stated measurement.
Example Sentence 1
The bracket measured 2.503 inches, which was within the print tolerance of plus or minus 0.005 inches.
Example Sentence 2
Any measurement outside the print tolerance required the part to be rejected.