Milling machine
Fresadora
- Date
- c. 1818 · confidence low
- Place
- Middletown, Connecticut, United States
- Credited to
- Robert Johnson and Simeon North (Middletown); John H. Hall (Harpers Ferry); the traditional attribution to Eli Whitney has been disproved
- People
- 👤 John H. Hall1781–1841👤 Simeon North1765–1852
- Field
- Tools
⚠️ Disputed: the sources disagree.
What it is
A machine that cuts surfaces with a rotating multi-toothed tool, replacing hand filing. It made interchangeable parts practical in arms manufacture.
There is no evidence that Whitney used a true milling machine: the so-called 'Whitney machine of 1818' appears to postdate his death (1825). True milling machines appeared between 1814 and 1818 at federal arsenals and associated workshops (Johnson, North). Gay & Silver (1830s) improved vertical positioning.
What it led to
- The Springfield and Harpers Ferry arsenals as centres of precision
- The machine-tool industry of the Connecticut Valley
- Brown & Sharpe's universal milling machine (1861)
Built on
Made possible
- Percussion revolver (Colt)1835-1836
- Colt revolver
- Universal milling machine
- Typewriter