Tools & manufacturing · c. 1824
Interchangeable parts
Parts made to gauges fit any assembly without hand filing.
John H. Hall achieved truly interchangeable rifle parts at Harpers Ferry Armory in the 1820s using machines and gauges. The American system of manufacturing that followed made mass production possible.
What it built on 1
What it led to 2
Related measurements
The dashed line marks when it first worked.
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