UK 07The Lineage of British Grinding Machines

Sandstone and emery: grinding hulls and flat references (1823–1867)

Sheffield's grinding hulls

In the early 19th century, Britain's largest "grinding industry" was the cutlery grinding of Sheffield. Knives, forks, scissors and scythes were ground on large wheels of natural sandstone turned by river waterwheels. In the Porter Brook valley in the city, a water-powered grinding workshop going back to the 1500s, Shepherd Wheel, still survives; it went on grinding blades by water power into the 1930s, after other grinding hulls had gone electric^[35].

The grinding hulls also shortened the lives of the craftsmen. In an 1843 book, the Sheffield physician G. Calvert Holland wrote that the old hulls stood by rivers several kilometers from town, with good air, and work stopped when there was too much or too little water; but after the steam engine came, grinding went on all day in buildings crammed onto high ground in town, and dry grinding without water spread because it was faster. Many fork grinders, who constantly breathed in the stone and iron dust rising from the wheels, died before the age of 30^[3]. Ways of preventing dust existed from the 1820s, and grinding machines with dust extraction were available by 1824, but in many hulls the grinders simply wrapped a cloth around their faces^[1]. Holland described, with a diagram, a system that collected an intake at each wheel into a single underfloor duct and blew the dust outside with a fan belt-driven from the wheel shaft, and recommended it at a cost of about one pound per grinder^[3]. The guards and dust extraction of today's grinders, and wet grinding with coolant, have the experience of these grinding hulls behind them.

The first grinding machines: pulleys, copper disks and large stone wheels

In engineering works, too, attempts began to bring parts to size by grinding. In 1838 James Whitelaw of Scotland built an iron cylindrical grinder for grinding the rims of belt pulleys. A 42-inch (about 1.07 m) wheel and the work turned in opposite directions; the infeed was by hand, and the traverse across the wheel width was powered. He reported that it finished fifteen 18-inch pulleys in 10 hours and, after a year and a half of use, was as sturdy as a self-acting lathe. Whitelaw wrote of the advantages of grinding: thin castings are too hard for a lathe tool but that does not matter to a grinder, and since thin pulleys can be finished, material is saved too^[1].

In his 1839 patent, J. G. Bodmer ground hardened iron cylinders and flat surfaces with a 31-inch copper disk charged with emery, and later ground the guideways of lathe beds on a vertical-spindle grinder. James Nasmyth built a large disk grinder with twelve blocks of natural stone screwed to a cast-iron ring about 7 ft in diameter, with automatic feed of the work^[1]. All were devices from an age when a "grinding wheel" was either natural stone or soft metal charged with emery powder.

Whitworth: stop grinding and make flat surfaces by scraping

Ironically, the biggest event of this period in Britain was an argument to "stop grinding." In 1840 Joseph Whitworth read a paper on making flat surfaces (surface plates and guideways) to the British Association in Glasgow. At the time it was normal to "grind" filed surfaces by rubbing them together with emery powder. Whitworth pointed out that rubbing them together only transfers the error of one surface to the other and never produces a true plane; the powder collects at the edges and rounds them, and emery grains embed in the metal and wear the sliding surfaces early. He then showed that by trying three plates against each other in turn and scraping off only the high spots with a scraper, the errors could be checked and removed step by step^[2]. The locomotive superintendent of the Liverpool and Manchester Railway wrote to Whitworth that a slide valve ground in with emery had worn a groove 1/8 inch (about 3 mm) deep and its face had become hollow in five months, while a scraped valve was still true and looked good for another five months^[2].

Whitworth did use grinding for standards that needed hardness, though. At the Institution of Mechanical Engineers in Manchester in 1857, he showed an internal gauge with a 0.5770-inch bore into which cylindrical gauges of 0.5769 and 0.5770 inches were inserted, demonstrating that a difference of one ten-thousandth of an inch (about 2.5 μm) made a completely different fit. These gauges were finished by grinding after their surfaces were hardened, and in his works he measured to one twenty-thousandth of an inch^[2]. Flat references made by scraping, hardened size standards finished by grinding and measured: this division of labor continues in machine tool factories today.

The invention of the grinding wheel: vitrified, silicate and rubber

For the grinder to become a "machine," artificial wheels of consistent quality were needed, and Britain filed many patents here. In 1825 natural corundum (almost pure alumina) arrived from India and was found to cut better than emery. By 1837 solid wheels of bonded emery were being made in Britain, and in 1842 Henry Barclay patented a wheel whose grains were vitrified. In 1857 Deplanque patented bonding with vulcanized rubber, and such wheels were being made in London by 1862. The rubber bond later survived as the regulating wheel of centerless grinding^[1].

In 1859 Frederick Ransome patented a wheel made by bonding grains of emery and the like with potassium or sodium silicate and firing it. It is regarded as the first silicate bond, and when the engineer Donkin tested it in 1867 it reportedly cut more than 50 times as much as the best natural Newcastle grindstone^[1]. Among devices for keeping works grinding wheels flat, there were also William Muir's double grindstone of 1853 (two wheels rubbing each other at different speeds) and David Fisher's patent for an artificial emery wheel of 1856; a model and samples of these are held by the Science Museum in London^[4]. In 1853 Barker and Holt of Manchester patented a machine that ground hardened steel balls by rolling them with emery and water between grooves in two iron plates, a method that led to the grinding of ball-bearing balls^[1].

What changed in this era. Grinding began to move from "sharpening tools" and "polishing surfaces" to "bringing hard parts to size." But for flat references Whitworth's scraping was the star, and the grinder was still a supporting player to the lathe and the scraper. Scraping still survives on the sliding surfaces of machine tools today because it creates oil pockets on a ground surface and lets you correct the surface while checking the bearing.

Grinder makers are born, and Guest's book (1887–1915)

It was Brown & Sharpe (the universal grinder of 1876) and Norton (the heavy grinder of 1900) in the U.S. that turned precision grinding machines into an industry (see the chapter on American grinding machines). In Britain, home-built grinders first appeared as special machines, for railway parts and the like. Beyer, Peacock, the Manchester locomotive builder, was offering a vertical-spindle grinder for grinding valve-gear links in 1887^[1].

Churchill: the Manchester maker that focused on grinders

In 1906, in Manchester, Churchill Machine Tool Company was founded. At first it made various machine tools, but it soon focused on grinders. Looking back on the company's 50 years, a 1957 trade journal said that when it started, British works regarded the grinder as "a necessary evil for machining things too hard to cut any other way," and that the motor industry gave grinding its first opportunity^[6]. In 1919 it built a new works at Broadheath (Altrincham) near Manchester, and the Pendleton works was sold^[13][14].

Churchill's early machines showed that American-style grinders could be built in Britain too. In 1912 it built a motor-driven plain grinder fitted with a Norton wheel (26 in diameter × 3 in wide) and a 20 × 60-inch universal grinder, and around the same time a precision surface grinder weighing about 20 tons to finish planed cast-iron plates up to 7 ft long × 6 ft wide. It was introduced at the time as "the largest precision surface grinder yet built." In 1913 the Pendleton works also brought out a vertical-spindle surface grinder and a piston ring grinder of 30–40 in diameter^[9]. Finishing by grinding the large flat surfaces that had been planed and then scraped: that trend had begun in Britain too.

Lumsden and Coventry Gauge

In Gateshead in the northeast, Lumsden Machine Company became a company making only grinders from 1910, brought out an oscillating tool grinder, and concentrated on tool grinders during World War I^[8]. In 1913 Harry Harley, who had worked his way up from apprentice at Alfred Herbert in Coventry, founded Coventry Gauge and Tool Company, a gauge and tool company that would later make the Matrix thread grinder^[10].

Guest's Grinding Machinery: thinking about grinders mathematically

In 1915 James J. Guest published Grinding Machinery in London. Guest was an engineer also known for "Guest's law" of material strength (ductile materials yield at a constant shear stress), and he had designed grinders bearing his own name^[12]. From the relationships among wheel diameter, work diameter and surface speeds, and depth of cut, the book gave formulas for the boundary between a wheel that "breaks down too fast to hold size" and one that "glazes and stops cutting," and discussed distortion in dry grinding, the role of coolant, the need to force oil into the high-speed spindles of internal grinding, spindle bearing design, and the time and cost of the work. The American researcher Woodbury rates it as the first work to bring engineering analysis to grinding machines and their use^[1]. Churchill and the American firm Landis drew and supplied the illustrations specially^[12].

What it means on the shop floor. The ideas behind grinding conditions, such as "the ratio of wheel speed to work speed," "depth of cut and feed," and "use a softer wheel and save labor rather than wheel," were set out mathematically by Guest in 1915. For today's guidelines on grinding conditions, see Grinding Basics: "Grinding conditions".

Automobiles, thread grinding and centerless (1918–1932)

Matrix thread grinders: from single-rib to multi-rib

Hardened threads such as thread gauges, taps and hobs distort in hardening, so finishing them on a lathe or by turning does not give the accuracy needed. At the end of World War I, Coventry Gauge & Tool brought out its first Matrix thread grinder. At first it ground the thread groove one pass at a time with a wheel dressed with a single rib, but later it incorporated a multi-rib diamond dresser, patented by Harley's son Stanley Harley, so that a wheel with many ribs could grind in one go^[11]. A 1949 British book on thread grinding said the company had "the experience of a pioneer and raised the standard of thread grinding today"^[19].

Olympia 1924: grinding automobile parts

At the machine tool exhibition at Olympia in London in September 1924, British grinders were lined up as machines for automobile mass production. Churchill showed four machines: a grinder that ground the hardened splined shafts of cars one face at a time with the peripheries of two wheels instead of a formed wheel, a 6 × 18-inch heavy plain grinder, and an internal grinder designed to cut setup and gauging time. The wheel spindles were of a new standard construction, with adjustable plain bearings near the wheel and rolling bearings at the belt pulley end^[8]. A. A. Jones & Shipman of Leicester also showed internal and universal grinders. The wheel was belt-driven from a high-speed countershaft, and coolant was pumped onto the work^[8].

In surface grinding, Lumsden caught the eye. It showed, as a new principle of surface grinding, a "planetary head" surface grinder in which a wheel of small segments turned on its own axis while also moving in a circle, and its horizontal-spindle surface grinders with 30-inch wheels ground the flat faces of parts for locomotives, textile machinery and electrical machinery. The exhibition report said such segmental-wheel surface grinders had become machines that competed head-on with milling machines and planers^[8]. The use of grinding in the British motor industry lagged slightly behind the U.S., but by 1925 it was in full use at Vauxhall^[1].

Scrivener, the centerless specialist

Centerless grinding, which entered mass production in the U.S. in the 1920s, also produced a specialist maker in Britain. After World War I, Arthur Scrivener of Birmingham was managing a local machine tool company, but in 1932 he set up his own works and company in Tyburn Road. His first centerless grinder was a success, so he concentrated on them, improving automatic operation in particular. His first patent (1933) was for a grinder bearing, and over his life he took out more than 40 patents on centerless grinders and other machines^[15]. A US patent he filed in 1944 was the basis of the centerless thread grinding, grinding hardened set screws in a single pass, developed by the Landis Machine Company in the U.S.^[1].

In 1932 the trade journal The Engineer took up centerless grinding in its series "Precision Grinding Machines" and described Churchill's machine in detail. The grinding wheel was 20 inches in diameter and the regulating wheel 12 inches, and size was set by feeding the regulating wheel toward the grinding wheel. Citing Churchill's explanation, the article listed the causes of chatter as work center too high, wheel too hard or too fine, work rest blade at too steep an angle or too thin, and looseness somewhere in the setup^[16]. These are almost the same as today's cautions for setting up centerless grinding. The same series also featured Lumsden's vertical-spindle surface grinder. A segmental wheel driven by a 25 hp motor worked over a reciprocating table like a planer's, with hydraulic feed; by combining the table stroke with cross-feed of the wheelhead, it could grind all the way around a surface shaped like a picture frame^[17].

What it means on the shop floor. Today's processes of grinding thread gauges, taps and hobs "after hardening," mass-producing bearings and pins "by centerless grinding," and grinding large flat surfaces "with segmental wheels" already appear clearly in the British trade journals of this period. For centerless setup, see Grinding Basics: "Setup", and for thread accuracy, the threads page.

⚑World War II and grinding machines (1930s–1945)

In the years of rearmament, what the British government worried about first was the gauges needed to make weapons. From 1930 the gauge subcommittee of the Supply Board studied the question and pointed out that Britain lacked the jig borers, dividing heads and thread grinders essential for making gauges; on its recommendation, steps were taken to make them at home^[18].

Even so, when the war began there was a serious shortage of grinders. According to the British official war history Factories and Plant, the hardest machines to obtain for producing fuzes and 20 mm shells were automatics, semi-automatic lathes and centerless grinders, and most had to be bought from the U.S. Britain produced 11,903 grinders in 1942, but grinder imports from the U.S. reached about 11,000 in the peak year, equal to 92% of domestic production. Moreover, a high share of the imports were expensive special machines, so dependence was even greater than the numbers suggest^[18].

The government drew up 28 schemes worth about £300,000 to expand grinder production, and in December 1942 pushed ahead with a plan to make at home substitutes for American-type machines not previously built in Britain. Most types were assigned to a single company, but automatics and surface grinders were assigned to five companies. They arrived, however, only after the war's peak had passed^[18]. In cutting tools as well, production of ground taps lagged because of the shortage of thread grinders and the great variety of sizes^[18].

Thread grinder makers grew suddenly. Coventry Gauge & Tool's workforce reached 6,000 at one point, and besides gauges, measuring instruments and tools it made grinders for grinding the root forms of jet engine (gas turbine) blades. Its founder, Harley, oversaw 20 factories in government work^[11][10]. A 1949 book writes that in wartime, newly trained workers and women ran thread grinders, and that thread grinding changed from the master craft of the gauge room into a production process^[19]. What made grinding something "anyone could do" was improved machines and wheels formed by pressing a roll against them, that is, crush dressing, and multi-rib wheels. The overall picture of wartime machine tool control is covered in Chapter 3, "The Two World Wars and Machine Tool Control".

Postwar grinders and industry reorganization (1949–1979)

The thread grinder perfected

The 1949 book Thread Grinding and Measurement describes British thread grinders after the war. Newall's Model 836 of Peterborough placed the motor inside the body to isolate vibration from the bed, ran a 16-inch wheel at up to 5,000 ft/min (about 25 m/s), fed in 0.0002-inch steps, and could change between a diamond dresser and a crush-forming roll in a few minutes. The Matrix 16G had a multi-rib dresser, a multi-rib crushing attachment and a single-rib dresser, with a built-in pitch-error correction device. Four ways of grinding were used as needed: traverse grinding with a single rib, traverse grinding with two ribs or multiple ribs, and plunge grinding with a multi-rib wheel in one pass^[19]. The book even wrote that in wheel-dressing devices "British design is second to none"^[19].

Jones & Shipman's 540 and the Diaform

Among toolroom surface grinders, the Model 540 of Jones & Shipman of Leicester became the standard. An article on the 1954 European Machine Tool Exhibition in Milan called the 540 "the well-known hydraulic surface grinder"^[20]. It was a toolroom surface grinder with a hydraulically reciprocated table under a horizontal-spindle wheel, and it was also used as the demonstration base for the wheel-forming device described below^[22].

To grind formed parts on a surface grinder, the wheel must be given an accurate form. At the 1958 machine tool exhibition at Olympia, Toolmasters (Hillingdon, west of London) demonstrated the Diaform in its new Model 5/1, fitted to a Jones & Shipman 540. A pantograph reduced the movement of a stylus tracing a template by 10:1 and passed it to a diamond, copying a precise form onto the wheel. There were versions for cylindrical, surface and jig grinders, and one was also demonstrated on a jig grinder, grinding the tooth form of a shaving die for internal gears^[22]. It was a tool for reproducing "form grinding" (copying a shape onto the wheel) from a template rather than by the craftsman's feel, and it later came to Japan as well (see "Links with Japan" below).

Safety regulations for grinding wheels

In postwar Britain the safety of grinding wheels became a major legal issue. A 1955 court ruling held that under the Factories Act grinding wheels had to be securely fenced without exception, which threatened to require guards so complete that the wheels could not be used. In 1956 the government issued draft regulations relaxing the fencing to what the work required, but the trade unions objected, and the rules were rewritten to cover the mounting, speeds, storage and marking of wheels. At the public inquiry of 1968–69, the unions asked for the training of people who mount wheels to be included in the regulations, and the inspector recommended that the formal training of those who mount wheels be specified by subjects in a schedule to the regulations. A proposal to make the marking of wheels (abrasive, grain size, grade and bond, BS 1814) a legal duty was not adopted, on the grounds that it was not directly related to safety^[21]. The result was the Abrasive Wheels Regulations 1970.^[26] In Japan too, the Industrial Safety and Health Regulations require special training for changing and test-running grinding wheels, but in Britain it was these regulations that made law of the idea of training and appointing the people who mount wheels.

Corporate consolidation

From the late 1950s, the old grinder makers were absorbed into large groups. In 1958 Coventry Gauge & Tool merged with the Rockwell group^[11]. In November 1960 BSA (Birmingham Small Arms) made a bid of about £8.5 million for Churchill of Altrincham. Churchill made medium and small precision grinders, and its most profitable year had been 1953–54^[23]. The centerless maker Scrivener appears in a 1963 trade journal index as Wickman-Scrivener duplex grinders, its name paired with Wickman^[24]. In 1972, combining the Matrix and Churchill names, Matrix-Churchill was selling grinders and lathes as the machine tool division of the steel tube giant Tube Investments (TI)^[27].

Even so, Britain's machine tool industry was in trouble in the 1970s. In a House of Commons debate in January 1979, an MP complained that the state car company British Leyland had placed an order with a German firm even though Churchill of Blaydon (in the northeast) could have supplied similar machines^[28]. The decline of the industry as a whole is covered in Chapter 4, "NC, FMS, Industrial Decline and Revival".

★Ultra-precision and British grinders today (1993–)

In the 1980s and 1990s, many British grinder makers disappeared or became parts of foreign companies. In the 1990s the Matrix Churchill name became known in a different way: through the trial over exports of machines to Iraq and the Scott Report that investigated it. In a House of Commons debate in February 1996, the discovery after the Gulf War of 30 Matrix Churchill lathes at Iraqi nuclear facilities was among the issues raised, and the treatment of machine tools as "machines that make weapons" subject to export controls became a major debate^[31].

Meanwhile, grinders focused on specialty fields are still made in Britain. Rochdale's Holroyd (founded 1860) received the Queen's Award in 1993 for machines that mill and grind screw compressor rotors and in 2004 for its thread and gear grinding technology, and since 2010 has been part of the group of China's Chongqing Machinery & Electric (CQME)^[30] (for details, see the next chapter, "The Lineage of British Gear Machines").

In ultra-precision grinding, Cranfield University did important work. The large optics grinder BoX developed by the university can grind parts up to 1.5 m; results published in 2010 showed it grinding a 1 m hexagonal mirror segment of the kind used in extremely large telescopes, correcting errors to hold the form of the 1 m surface within ±1 μm. The idea is that improving form accuracy by grinding and reducing subsurface damage shortens the polishing that follows^[32]. Today France's Fives makes grinders under the Landis and Cranfield Precision brands, and in May 2026 it announced the Landis TTG 3000, a new grinder combining British and American technology. The wheels and the workpiece are each mounted on separate turrets, so that several surfaces can be ground in one setup^[33][34]. The year in which British CNC grinders began could not be confirmed in primary sources in this research.

What it means on the shop floor. When looking at a used British grinder, knowing the name changes (Coventry Gauge → Matrix, Churchill → Matrix-Churchill, Scrivener → Wickman-Scrivener, Landis's British business → Fives) gives you leads on where to ask about parts and drawings. Many are inch machines, so check the units on the dials too.

Links with Japan

What linked British grinders with Japan was not so much the machines themselves as tools for form grinding. In 1965 Kuroda Precision Industries, newly renamed from Kuroda Kyohan Seisakusho (Kuroda Gauge Works), tied up with Britain's Diaform and brought out a surface grinder with a built-in wheel-forming device^[25] (Japanese Archive, Chapter 3 timeline). British pantograph ideas thus entered the work of Japanese toolrooms grinding the shapes of dies and gauges on surface grinders.

At the 6th Japan International Machine Tool Fair, held at Harumi, Tokyo, in 1972, Britain showed Churchill grinders, Jones & Shipman grinders, Matrix-Churchill grinders and lathes, and Wickman internal grinders. A report from the British Embassy in Tokyo noted with satisfaction that the Diaform device was demonstrated not only on its own stand but also on machines of Japanese, Italian and Swiss exhibitors, and gave Britain's share of Japan's machine tool imports as 4.5% for January–September 1972 (3.7% the year before)^[27]. According to the report, Japan had become the world's third-largest producer of metal-cutting machine tools the year before, in 1971. In grinding machines, Japan began by taking American machines as models (the chapter on American grinding machines), and in the 1970s it moved ahead in production grinding with CBN wheels (Japanese Archive, Chapter 3 "CBN and high-speed grinding" event).

FAQ

Was Whitworth against grinding?

What he opposed was making "flat references" such as surface plates and guideways by rubbing them together with emery. In his 1840 paper he pointed out that rubbing only transfers errors to the other surface, rounds the edges and leaves emery grains in the metal, and recommended trying three plates against each other and scraping off the high spots. On the other hand, he finished hardened cylindrical gauges by grinding and demonstrated differences of one ten-thousandth of an inch with them. Scraping for flat surfaces, grinding for hard size standards: that was his division of labor.

Who were the leading British grinder makers?

They include Churchill (1906, Manchester) for cylindrical, internal, surface and centerless grinders; Matrix (Coventry Gauge & Tool, founded 1913) for thread grinders; Jones & Shipman (Leicester), maker of the 540 toolroom surface grinder; Lumsden (Gateshead) for surface grinders; Scrivener (1932, Birmingham) for centerless grinders; Newall (Peterborough) for thread grinders; and Holroyd (Rochdale) for rotor, thread and gear grinding. Many joined large groups between the 1950s and 1980s and changed their names.

Did Britain have enough grinders in World War II?

No. According to the British official war history, against Britain's production of 11,903 grinders in 1942, grinder imports from the U.S. reached about 11,000 in the peak year, equal to 92% of domestic production. Centerless and thread grinders were especially short, and a plan was made for five companies to build substitutes for American-type surface grinders.

What are the Abrasive Wheels Regulations 1970?

Britain's safety regulations for grinding wheels. They set rules for the guarding, speeds, mounting and storage of wheels, and the public inquiry behind them recommended that formal training for the people who mount wheels be specified in the regulations. Like Japan's special training for changing and test-running grinding wheels, they put weight on "training the people who mount the wheels."