From Graces Guide
Note: The name was sometimes recorded as Henry Maudsley.
Henry Maudslay (1771–1831) of Maudslay, Sons and Field was a British machine tool innovator, tool and die maker, and inventor. He is considered a founding father of machine tool technology.
1771 August 22nd. Born at Woolwich, the son of Henry Maudslay (1725-1780) (sometimes Maudsley; d. c.1780) and his wife Margaret Whitaker. Henry (the father) who was a native of Clapham in Yorkshire, who had served as a wheelwright in the Royal Artillery, was wounded in action and had become a storekeeper at the Woolwich Arsenal.
Maudslay's father died while he was a boy and this was probably why he himself began work in the arsenal at an early age, filling cartridges at the age of 12. He then transferred to a woodworking shop followed by a smithy. He demonstrated considerable skill at the forge and with machinery, and attracted the attention of the engineer and inventor Joseph Bramah.
1789 Maudslay joined Bramah when was struggling to develop a new type of lock, and it was Maudslay who devised and constructed the machines capable of producing the precisely designed parts for this apparatus. He was probably also responsible for the self-tightening leather collar which made Bramah's hydraulic press work efficiently.
1790 Maudslay married Sarah Tindale (1761/2–1828), who had been Bramah's housekeeper; they had four sons and three daughters.
1794 Designed a new form of slide rest for the lathe, which is described as the most important and epoch-marking steps in the world's industrial history. 
1798 After nine years with Bramah, Maudslay had a dispute with his employer about his wages and left to set up business on his own, acquiring premises first in Wells Road, off Oxford Street, and then in Margaret Street, Marylebone where he set up his own precision workshop as Henry Maudslay and Co
1800 Following earlier work by Samuel Bentham, his first major commission was to build a series of 42 woodworking machines to produce wooden rigging blocks (each ship required thousands) for the Navy under Sir Marc Isambard Brunel. The machines were installed in the purpose-built Portsmouth Block Mills, which still survive, including some of the original machinery. This was the first well known example of specialized machinery in an assembly line type factory.
He applied the ideas of interchangeable parts including nuts and bolts (before that all nuts and bolts were made as matching pairs only), and developed an industrial screw-cutting lathe, allowing standardisation on screw thread sizes for the first time.
1802 Moved from Wells Street to 75 Margaret Street
1805 Maudslay intoduced a bench micrometer that was capable of measuring to one ten thousandth of an inch (he called it the "Lord Chancellor"). Having also developed a means to desalinate seawater for use in marine boilers, his company also specialised in marine steam engines.
1809 Forty-four machines for the Portsmouth Blocks Mills completed and commissioned
1810 David Napier moved south, initially to work for Henry Maudslay.
Many outstanding engineers trained or developed their expertise in his workshop including -
- Richard Roberts (with Maudslay 1814 - 1816)
- David Napier (with Maudslay ~1815 - ~1816)
- Joseph Clement (with Maudslay 1815 - 1817)
- Joseph Whitworth started 1825
- James Nasmyth from 1829
- William Muir (arrived 2 months after Maudslay's death)
- Francis Lewis
A scholarly review of the work of Henry Maudslay and the above-mentioned engineers was published in 2002 
1810 The business moved from 75 Margaret Street to Lambeth, and he took on a partner, Joshua Field; the firm became Maudslay and Field. Maudslay went on to improve the slide lathe, as well as inventing new machine tools and manufacturing flour mills, saw mills, mint machinery and steam engines.
1816 'A new steam vessel named the Regent, of 112 tons, was tried on Saturday morning on the River. She went from Blackfriars Bridge to Battersea Bridge in thirty minutes, and back through London Bridge in fifty-two minutes. A great desideratum is, we understand, obtained in the construction of the mechanical apparatus by a considerable reduction in the weight. The steam engine of a twenty-four horse power, the paddle wheels, and the machinery necessary to give and convey the movement, weighing only five tons.- This vessel is executed under the direction of Mr. Brunel, of Chelsea, by Mr. Maudslay;, and it was decided by the experiment that she was the best going vessel on the river.'
1829 Henry Maudslay, Lambeth, Engineer, became a member of the Institution of Civil Engineers.
1831 February 15th. Henry Maudslay died at Lambeth and was buried in Woolwich Churchyard.
His eldest son, Thomas Henry Maudslay, and his third son, Joseph Maudslay made particular contributions to the family business. The company, Maudslay, Sons and Field, was one of the most important British engineering manufactories of the nineteenth century, finally closing around 1900.
The work of Henry Maudslay, and his influence in the context of engineering development, is the subject of a new book by David Waller, published in 2016 
Sources of Information
- The Engineer 1895/10/18
- 'Matthew Murray 1765-1826 and the firm of Fenton Murray and Co 1795-1844' by Paul Murray Thompson, published by Paul Murray Thompson, 2015, p.156
- 'Henry Maudslay & The Pioneers of the Machine Age' edited by John Cantrell and Gillian Cookson, Tempus Publishing, 2002
- Morning Chronicle, 24 June 1816
- Mechanics Magazine 1824/03/13
- Mechanics Magazine 1824/03/20
- 1829 Institution of Civil Engineers
- 'Iron Men: How One London Factory Powered the Industrial Revolution and Shaped the Modern World', by David Waller, Anthem Press, 2016