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50-405: The Whitworth thread was the world's first national screw thread standard, devised and specified by Joseph Whitworth in 1841. Until then, the only standardization was what little had been done by individual people and companies, with some companies' in-house standards spreading a bit within their industries. Whitworth's new standard specified a 55° thread angle and a thread depth of 0.640327 p and

100-599: A 2.75 inches (69.85 mm) bore, a 12 pounds 11 ounces (5.75 kg) projectile and a range of about 6 miles (10 km). The spirally-grooved projectile was patented in 1855. This was rejected by the British Army, who preferred the guns from Armstrong , but was used in the American Civil War. While trying to increase the bursting strength of his gun barrels, Whitworth patented a process called "fluid-compressed steel" for casting steel under pressure and built

150-475: A 47.5° thread angle and has its own set of head sizes. BA threads have diameters of 6 mm ( 0BA ) and smaller, and were and still are particularly used in precision machinery. The Whitworth 55° angle remains commonly used today worldwide in form of the 15 British standard pipe threads defined in ISO 7, which are commonly used in water supply, cooling, pneumatics, and hydraulic systems. These threads are designated by

200-790: A German company specializing in microscopes and thus equipped with tooling capable of handling threads in inches and in Whitworth. The 5 ⁄ 32  in Whitworth threads have been the standard Meccano thread for many years and it is still the thread in use by the French Meccano Company. Fixings for garden gates traditionally used Whitworth carriage bolts , and these are still the standard supplied in UK and Australia. British Morris and MG engines from 1923 to 1955 were built using metric threads with bolt heads and nuts dimensioned for Whitworth spanners and sockets. In 1919, Morris Motors took over

250-460: A Whitworth Senior Scholarship was agreed by the trustees to support Postgraduate Research leading to a MPhil , PhD or EngD . Richard Copley Christie was a friend of Whitworth's. By Whitworth's will, Christie was appointed one of three legatees , each of whom was left more than half a million pounds for their own use, 'they being each of them aware of the objects' to which these funds would have been put by Whitworth. They chose to spend more than

300-453: A cotton spinner at Amber Mill, Oakerthorpe in Derbyshire. The plan was that Whitworth would become a partner in the business. From the outset he was fascinated by the mill's machinery and soon he mastered the techniques of the cotton spinning industry but even at this age he noticed the poor standards of accuracy and was critical of the milling machinery. This early exposure to the mechanics of

350-619: A fifth of the money on support for Owens College , together with the purchase of land now occupied by the Manchester Royal Infirmary . In 1897, Christie personally assigned more than £50,000 for the erection of the Whitworth Hall , to complete the front quadrangle of Owens College. He was president of the Whitworth Institute from 1890 to 1895 and was much interested in the medical and other charities of Manchester, especially

400-872: A new steel works near Manchester. Some of his castings were shown at the Great Exhibition in Paris c.  1883 . One of the most prominent forms of his generosity was his development of the Whitworth Scholarships with the Institution of Mechanical Engineers. Still running to this day, this provides financial opportunities for young engineers with a strong blend of academic and practical abilities. The Whitworth Scholarship programmes still exist with 10-15 scholarships being awarded each year. The scholarships are directed at outstanding engineers who, like Sir Joseph Whitworth, have excellent academic and practical skills and

450-418: A number between 1/16 and 6 that originates from the nominal internal diameter (i/d) in inches of a steel pipe for which these threads were designed. These pipe thread designations do not refer to any thread diameter. Other threads that used the Whitworth 55° angle include Brass Threads , British Standard Conduit (BSCon), Model Engineers' (ME), and British Standard Copper (BSCopper). The widely used (except in

500-489: A radius of 0.137329 p , where p is the pitch. The thread pitch increases with diameter in steps specified on a chart. The Whitworth thread system was later to be adopted as a British Standard to become British Standard Whitworth (BSW). An example of the use of the Whitworth thread are the Royal Navy 's Crimean War gunboats. These are the first instance of mass-production techniques being applied to marine engineering , as

550-445: A straight flank depth of h − 2 e = 0.49249224 p ) and a radius of r = e /(1 − sin Θ ) = 0.13732908 p . Below is the historical thread size table, not to be confused with G threads, which are actually in use as British Standard Pipe . For example a G½ (half inch) is 20.955mm in diameter. To simplify matters, the term hexagon is used in this section to denote either bolt head or nut. Whitworth and BSF spanner markings refer to

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600-454: Is H = p /(2tan Θ ) = 0.96049106 p . However, the top and bottom 1 ⁄ 6 of each of these triangles is cut off, so the actual depth of thread (the difference between major and minor diameters) is 2 ⁄ 3 of that value, or h = p /(3tan Θ ) = 0.64032738 p . The peaks are further reduced by rounding them with a 2×(90° − Θ ) = 180° − 55° = 125° circular arc. This arc has a height of e = H sin Θ /6 = 0.073917569 p (leaving

650-509: Is the same in both systems except that the thread pitch for the 1 ⁄ 2  in bolt is 12 threads per inch (tpi) in BSW versus 13 tpi in the UNC. The form of a Whitworth thread is based on a fundamental triangle with an angle of 55° at each peak and valley. The sides are at a flank angle of Θ = 27.5° perpendicular to the axis. Thus, if the thread pitch is p , the height of the fundamental triangle

700-524: The British Standard Whitworth standard: At least 41 thread sizes have been defined, ranging from ⁄ 16 to 18, although of these only 15 are included in ISO 7 and 24 in ISO 228. The size number was originally based on the inner diameter (measured in inches) of a steel tube for which the thread was intended, but contemporary pipes tend to use thinner walls to save material, and thus have an inner diameter larger than this nominal size. In

750-516: The Whitworth Scholarship for the advancement of mechanical engineering. He donated a sum of £128,000 to the government in 1868 (approximately £6.5 million in 2010) to bring "science and industry" closer together and to fund scholarships. In 1869, Queen Victoria made Whitworth a baronet . In January 1887 at the age of 83, Sir Joseph Whitworth died in Monte Carlo where he had travelled in

800-1008: The Whitworth Society was founded by Prof. Hele-Shaw FRS , then president of the Institution of Mechanical Engineers to support all Whitworth Scholars and to promote engineering in the UK. The Society brings together those Whitworth Scholars who have benefited from Sir Joseph Whitworth's generosity. British Standard Pipe British Standard Pipe ( BSP ) is a set of technical standards for screw threads that has been adopted internationally for interconnecting and sealing pipes and fittings by mating an external ( male ) thread with an internal (female) thread. It has been adopted as standard in plumbing and pipe fitting , except in North America, where NPT and related threads are used. Two types of threads are distinguished: These can be combined into two types of joints: The thread form follows

850-486: The steam hammer ) and Richard Roberts . Whitworth developed great skill as a mechanic while working for Maudslay, developing various precision machine tools and also introducing a box casting scheme for the iron frames of machine tools that simultaneously increased their rigidity and reduced their weight. Whitworth also worked for Holtzapffel & Co (makers of lathes used primarily for ornamental turning ) and Joseph Clement . While at Clement's workshop he helped with

900-436: The 1830s, using engineer's blue and scraping techniques on three trial surfaces. Up until his introduction of the scraping technique, the same three-plate method was employed using polishing techniques, giving less accurate results. This led to an explosion of development of precision instruments using these flat-surface generation techniques as a basis for further construction of precise shapes. His next innovation, in 1840,

950-662: The American Civil war. Whitworth was created a baronet by Queen Victoria in 1869. Upon his death in 1887, Whitworth bequeathed much of his fortune for the people of Manchester , with the Whitworth Art Gallery and Christie Hospital partly funded by Whitworth's money. Whitworth Street and Whitworth Hall in Manchester are named in his honour. Whitworth's company merged with the W.G. Armstrong & Mitchell Company to become Armstrong Whitworth in 1897. Whitworth

1000-789: The Cancer Pavilion and Home, of whose committee he was chairman from 1890 to 1893, and which later became the Christie Hospital . Part of his bequest was used to construct the Whitworth Institute in Darley Dale. The university's Whitworth Art Gallery (formerly the Whitworth Institute) and adjacent Whitworth Park were established as part of his bequest to Manchester after his death. Nearby Whitworth Park Halls of Residence also bears his name, as does Whitworth Street , one of

1050-487: The Cycle Engineers' Institute (CEI) standard was used on British bicycles and motorcycles. It uses a thread angle of 60° compared to the Whitworth 55° and very fine thread pitches. The British Association screw thread (BA) standard is sometimes classed with the Whitworth standard fasteners because it is often found in the same machinery as the Whitworth standard. However it is actually a metric based standard that uses

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1100-758: The French Hotchkiss engine works which had moved to Coventry during the First World War. The Hotchkiss machine tools were of metric thread but metric spanners were not readily available in Britain at the time, so fasteners were made with metric thread but Whitworth heads. In the 2011 movie Cars 2 by Disney / Pixar , the vital clue to the discovery of the villain, Sir Miles Axlerod, is that he uses Whitworth bolts. Although Axlerod does not precisely resemble any real car (whereas numerous other characters are closely modelled on real cars), he seems most closely to match

1150-632: The US) British Standard Pipe thread, as defined by the ISO ;228 standard (formerly BS-2779), uses Whitworth standard thread form. Even in the United States, personal computer liquid cooling components use the G 1 ⁄ 4 thread from this series. The Leica Thread-Mount used on rangefinder cameras and on many enlarging lenses is 1 + 17 ⁄ 32  in by 26 turns-per-inch Whitworth, an artifact of this having been developed by

1200-545: The US, BSW was replaced when steel bolts replaced iron, but was still being used for some aluminium parts as late as the 1960s and 1970s when metric -based standards International Inch replaced the U.S. inch and U.K. inch in 1951-1964. American Unified Coarse (UNC) was originally based on almost the same Imperial fractions. The Unified thread angle is 60° and has flattened crests (Whitworth crests are rounded). From 1 ⁄ 4  in up to 1 + 1 ⁄ 2  in, thread pitch

1250-432: The bolt diameter, rather than the distance across the flats of the hexagon (A/F) as in other standards. Confusion can arise because each Whitworth hexagon was originally one size larger than that of the corresponding BSF fastener. This leads to instances where for example, a spanner marked 7 ⁄ 16  BSF is the same size as one marked 3 ⁄ 8  W . In both cases the spanner jaw width of 0.710 in,

1300-454: The country, telling each to make ninety sets exactly in all respects to the sample. The orders were executed with unfailing regularity, and he actually completed ninety sets of engines of 60 horsepower in ninety days – a feat which made the great Continental Powers stare with wonder, and which was possible only because the Whitworth standards of measurement and of accuracy and finish were by that time thoroughly recognised and established throughout

1350-632: The country. An original example of the gunboat type engine was raised from the wreck of the SS Xantho by the Western Australian Museum . On disassembly, all its threads were shown to be of the Whitworth type. With the adoption of BSW by British railway companies, many of which had previously used their own standards both for threads and for bolt head and nut profiles, and the growing need generally for standardisation in manufacturing specifications, it came to dominate British manufacturing. In

1400-482: The excellence of his designs and was financially very successful. In 1850, then a President of the Institution of Mechanical Engineers , he built a house called 'The Firs' in Fallowfield in south Manchester designed by Edward Walters . In 1854 he bought Stancliffe Hall in Darley Dale, Derbyshire and moved there with his second wife Louisa in 1872. He supplied four six- ton blocks of stone from Darley Dale quarry, for

1450-587: The first nationally standardised system; its adoption by the railway companies, who until then had all used different screw threads, led to its widespread acceptance. It later became a British Standard , " British Standard Whitworth ", abbreviated to BSW and governed by BS 84:1956. Whitworth was commissioned by the War Department of the British government to design a replacement for the calibre .577-inch Pattern 1853 Enfield , whose shortcomings had been revealed during

1500-503: The following quotation from the obituary from The Times of 24 January 1887 for Sir Joseph Whitworth (1803–1887) shows: The Crimean War began, and Sir Charles Napier demanded of the Admiralty 120 gunboats, each with engines of 60 horsepower , for the campaign of 1855 in the Baltic . There were just ninety days in which to meet this requisition, and, short as the time was, the building of

1550-428: The following sequence of blocks: Threads are normally right-hand. For left-hand threads, the letters, LH , are appended. Example: Pipe thread EN 10226 Rp 2 + 1 ⁄ 2 The terminology for the use of G and R originated from Germany ( G for gas , as it was originally designed for use on gas pipes; R for rohr , meaning pipe .) The standard ISO 7 - Pipe threads where pressure-tight joints are made on

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1600-401: The gunboats presented no difficulty. It was otherwise however with the engines, and the Admiralty were in despair. Suddenly, by a flash of the mechanical genius which was inherent in him, the late Mr John Penn solved the difficulty, and solved it quite easily. He had a pair of engines on hand of the exact size. He took them to pieces and he distributed the parts among the best machine shops in

1650-462: The hope of improving his health. He was buried at St Helen's Church, Darley Dale , Derbyshire. A detailed obituary was published in the American magazine The Manufacturer and Builder . He directed his trustees to spend his fortune on philanthropic projects, which they still do to this day. Whitworth popularised the three-plates method for producing accurate flat surfaces (see Surface plate ) during

1700-465: The industry forged in him the ambition to make machinery with much greater precision. His apprenticeship at Amber Mill lasted for a four-year term after which he worked for another four years as a mechanic in a factory in Manchester . He then moved to London where he found employment working for Henry Maudslay , the inventor of the screw-cutting lathe , alongside such people as James Nasmyth (inventor of

1750-429: The larger hexagons to BS 190 are now often colloquially referred to as 'pre-war' size, even though that is not strictly correct. The British Standard Fine (BSF) standard has the same thread angle as the BSW, but has a finer thread pitch and smaller thread depth. This is more like the modern "mechanical" screw and was used for fine machinery and for steel bolts. The British Standard Cycle (BSC) standard which replaced

1800-648: The lions of St George's Hall in Liverpool . He was conferred with Honorary Membership of the Institution of Engineers and Shipbuilders in Scotland in 1859. He was elected a Fellow of the Royal Society (FRS) in 1857 . A strong believer in the value of technical education, Whitworth backed the new Mechanics' Institute in Manchester (later UMIST ) and helped found the Manchester School of Design . In 1868, he founded

1850-565: The main streets in Manchester city centre , running from London Road to the south end of Deansgate. Near 'The Firs' a cycleway behind Owens Park is called Whitworth Lane. In Darley Dale is another Whitworth Park. In recognition of his achievements and contributions to education in Manchester, the Whitworth Building on the University of Manchester 's Main Campus is named in his honour. In 1923,

1900-487: The manufacture of Charles Babbage 's calculating machine, the Difference engine . He returned to Openshaw , Manchester, in 1833 to start his own business manufacturing lathes and other machine tools, which became renowned for their high standard of workmanship. Whitworth is attributed with the introduction of the thou in 1844. In 1853, along with his lifelong friend, artist and art educator George Wallis (1811–1891), he

1950-478: The modern standard metric version, it is simply a size number, where listed diameter size is the major outer diameter of the external thread. For a taper thread, it is the diameter at the "gauge length" (plus/minus one thread pitch) from the small end of the thread. The taper is 1:16, meaning that for each 16 units of measurement increase in the distance from the end, the diameter increases by 1 unit of measurement. These standard pipe threads are formally referred to by

2000-655: The new bore design was found to be prone to fouling and it was four times more expensive to manufacture than the Enfield, so it was rejected by the British government, only to be adopted by the French Army . An unspecified number of Whitworth rifles found their way to the Confederate states in the American Civil War , where they were called " Whitworth Sharpshooters ". The rifles were capable of sub- MOA groups at 500 yards. It

2050-402: The original Range Rover Classic . In reality, early model Range Rovers used parts with imperial dimensions, although the photograph of the villain's engine is virtually identical to the later 3.5-litre, single plenum Rover V8 (A design purchased from GM's Buick). Other thread standards: Joseph Whitworth Sir Joseph Whitworth, 1st Baronet (21 December 1803 – 22 January 1887)

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2100-466: The qualities needed to succeed in industry, who are wishing to embark/or have already commenced on an engineering degree-level programme of any engineering discipline. As of 2018, the Scholarship pays up to £5,450 per year for up to four years in the case of a full time undergraduate. The handling and administration of the awards is now carried out by the Institution of Mechanical Engineers . Since 2006,

2150-456: The recent Crimean War . The Whitworth rifle had a smaller bore of 0.451 inches (11.455 mm) which was hexagonal, fired an elongated hexagonal bullet and had a faster rate of twist rifling [one turn in twenty inches] than the Enfield, and its performance during tests in 1859 was superior to the Enfield's in every way. The test was reported in The Times on 23 April as a great success. However,

2200-497: The smaller size hexagon was adopted more widely to save metal and this usage persisted thereafter. Thus it is today common to encounter a Whitworth hexagon which does not fit the nominally correct spanner and following the previous example, a more modern spanner may be marked 7 ⁄ 16  BS to indicate that they have a jaw size of 0.710 in and designed to take either the (later) 7 ⁄ 16  BSW or 7 ⁄ 16  BSF hexagon. Whitworth fasteners with

2250-548: The width across the hexagon flat, is the same. Certain branches of industry used Whitworth fasteners with a smaller hexagon (identical to BSF of the same bolt diameter) under the designation "AutoWhit" or Auto-Whit and this series was formalised by the British Engineering Standards Association in 1929 as standard No. 193, with the 'original' series being No. 190 and the BSF series No. 191. During World War II

2300-472: Was a measuring technique called "end measurements" that used a precision flat plane and measuring screw, both of his own invention. The system, with a precision of one millionth of an inch (25  nm ), was demonstrated at the Great Exhibition of 1851. In 1841 Whitworth devised a standard for screw threads with a fixed thread angle of 55° and having a standard pitch for a given diameter. This soon became

2350-453: Was an English engineer , entrepreneur, inventor and philanthropist. In 1841, he devised the British Standard Whitworth system, which created an accepted standard for screw threads . Whitworth also created the Whitworth rifle , often called the " sharpshooter " because of its accuracy, which is considered one of the earliest examples of a sniper rifle , used by some Confederate forces during

2400-586: Was appointed a British commissioner for the New York International Exhibition. They toured around industrial sites of several American states, and the result of their journey was a report 'The Industry of the United States in Machinery, Manufactures and Useful and Applied Arts, compiled from the Official Reports of Messrs Whitworth and Wallis, London, 1854.' Whitworth received many awards for

2450-658: Was born in John Street, Stockport , Cheshire, where the Stockport Courthouse is today. The site is marked by a blue plaque on the back wall of the courthouse. He was the son of Charles Whitworth, a teacher and Congregational minister, and at an early age developed an interest in machinery . He was educated at Idle , near Bradford, West Riding of Yorkshire ; his aptitude for mechanics became apparent when he began work for his uncle. After leaving school Whitworth became an indentured apprentice to his uncle, Joseph Hulse,

2500-502: Was often called the " sharpshooter " because of its accuracy, which is considered one of the earliest examples of a sniper rifle . Queen Victoria opened the first meeting of the National Rifle Association at Wimbledon , in 1860 by firing a Whitworth rifle from a fixed mechanical rest. The rifle scored a bull's eye at a range of 400 yards (366 m). Whitworth also designed a large rifled breech-loading gun with

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