Whitworth, Surface Plates, and the Millionth of an Inch Machine

[Subdeacon Joe]

https://www.imeche.org/news/news-article/the-stunning-sensitivity-of-the-imeche-archive's-'millionth-machine

 

Quote

Invented by engineer Sir Joseph Whitworth in the 1840s, the Millionth Machine was so called owing to its ability to measure to one millionth of an inch. Before its invention, measuring to one sixteenth of an inch had been considered accurate. The machine would measure length or thickness by comparing the end measure of an object with a known standard.

In 1859 Whitworth demonstrated his machine at a meeting of the IMechE, showing how the device’s accuracy was such that it could show the expansion in length of a one-inch iron bar caused by being touched by a finger.

Born in Stockport in 1803, Whitworth focused his career on accuracy, standardisation and measurement. He made a series of inventions and improvements to existing machinery and tools which would come to revolutionise manufacturing methods in the 19th century and beyond. 

In 1868 Whitworth donated a large sum of money to the government for the creation of a scholarship that would support aspiring engineers who had already gained practical experience through an apprenticeship to gain the theoretical underpinning provided through a university education. The Whitworth Scholarships still exist in 2019.

 

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[Charlie Harley, #14153]

The world needs more engineers educated this way...

 

In 1868 Whitworth donated a large sum of money to the government for the creation of a scholarship that would support aspiring engineers who had already gained practical experience through an apprenticeship to gain the theoretical underpinning provided through a university education. The Whitworth Scholarships still exist in 2019.

[Subdeacon Joe]

5 minutes ago, Charlie Harley, #14153 said:

The world needs more engineers educated this way

 

So they don't do things like call out the counter-bore diameter for the clearance of a bolt head as +/- .0005".