GERMANY 06The Lineage of German Milling Machines and Machining Centers

Learning from America: the beginnings in Chemnitz (1866–1913)

In the mid-19th century, the main machines for cutting flat surfaces and grooves in metal were the planer and the shaper. They had a single tool and cut a little on each stroke. The milling machine, which cuts continuously with a rotating cutter, grew up in American armories, and in 1862 Brown & Sharpe's universal milling machine appeared, able to cut even helical grooves (for details, see the American chapter).

Germany began by importing this machine and copying it. In his 1959 History of the Milling Machine, Robert S. Woodbury of MIT wrote that continental makers in the 1870s and 1880s first used American-built milling machines, and later came to use inferior continental copies. Some copies are said to have copied even the name of the original American maker. In Woodbury's view, this situation lasted until about 1908^[2].

Reinecker and Loewe: two companies that took America as their model

Julius Eduard Reinecker of Chemnitz (Saxony) started with a tool shop and set up a factory in 1867; according to the biographical dictionary NDB, in 1872 he took America as his model for milling machines, grinding machines and relieving lathes and began building them^[3]. Woodbury, too, mentions Reinecker's 1867 machine in a note on the history of the vertical milling machine^[2]. An article by Peter Stölzel in the newsletter of the friends' association of the Chemnitz Industrial Museum also says that milling machine building in Chemnitz began with Reinecker in the early 1870s^[7]. Reinecker's machines were known for their high precision, and at the 1893 Chicago World's Fair it was the only German machine tool maker to exhibit^[3].

Ludwig Loewe of Berlin was not an engineer but a merchant. According to a paper by the economic historian Wolfram Fischer, before founding his company in 1870 Loewe toured the United States and brought back the American way of making things as it was: close cooperation between design and production, concentration on a few products, standardization, interchangeable parts and quality control. When he built a new machine tool factory in the mid-1890s he hired three American engineers, and the young Georg Schlesinger, who joined in 1897, started out as their interpreter and was put in charge of American-style tools, gauges and jigs and of preparing production of the main machine types: the universal milling machine, the lathe, the turret lathe and others^[4]. Schlesinger later became a professor at the Technische Hochschule Berlin and led research on production engineering in Germany (see Chapter 2).

Wanderer: milling machines built for bicycle parts

In 1890 the Chemnitz bicycle maker Winklhofer & Jaenicke (later Wanderer) began developing its own milling machines and special-purpose machines to make its parts accurately, because machines on the market were not precise enough. In 1899 it put one of the first knee-type milling machines, the “plain milling machine Nr. 1,” on sale to customers in Germany^[7][9]. According to Stölzel's article, this machine had a curved column with a horn, supported the end of the arbor (the bar that carries the milling cutter) on a center in the overarm, and took its feed from the spindle's step pulley through a four-step pulley. Around 1900 the universal Nr. 1 and Nr. 3, with swiveling tables, followed^[7].

Hülle's 1919 textbook describes Wanderer's plain milling machine as a machine modeled on the shaper, with a rotating spindle in place of the reciprocating ram. The spindle took thrust in both directions on the taper of its front bearing, and the rear bearing was arranged to let the spindle grow with heat^[12]. Factories with rows of machines driven by belts and step pulleys: these were machines of that era.

Gearboxes and closed columns: the answer to high-speed steel

In the early 20th century, the high-speed steel of Taylor and White in the U.S. spread, and tools could cut much faster and deeper. Then thin belts and step pulleys no longer gave enough power, and the deflection of the machine spoiled the surface finish. Around 1905, in its plain milling machine Nr. 2, Wanderer built in for the first time a feed gearbox at the bottom of the column. From 1909 it began to house the overarm support and the spindle gearbox inside a closed, rigid column and dropped the step pulley^[7].

By then the ranks of German makers had grown. The index of Hermann Fischer's 1905 textbook lists Reinecker's horizontal, vertical, long-work and parallel milling machines, and milling machines by Droop & Rein of Bielefeld and Ernst Schiess of Düsseldorf^[10]. Schiess, founded in 1866, built vertical lathes and gantry-type milling machines from around 1870 and grew into a maker of large machines^[1]. In 1913 Wanderer was exporting milling machines to Russia, Austria-Hungary, France and Italy, and the milling machines built at its Schönau works from 1899 to 1920 exceeded 10,000^[7]. Forty years after it started by copying, Germany had become an exporter of milling machines.

What it meant on the shop floor. On step-pulley machines, the belt had to be moved every time the speed was changed, and it slipped under heavy cuts. With a gearbox, the cutting power reached the spindle without loss, and the speed could be selected with a lever. The speed-change levers on today's manual milling machines are descendants of the mechanism of this period.

Gear drives, electric motors, heavy cutting and two world wars (1914–1945)

16-speed gear drive, and the surface milling machine without a knee

Hülle's 1919 textbook (4th edition) describes the changing German milling machine in detail. The new Wanderer milling machine took its power from the overhead line shaft through a single flat-belt pulley and was built to change speed with a gear speed box on the spindle side, in 16 steps from 16 to 352 rpm. Hülle gives the reason: because the cutting forces on a milling machine are large, the weaknesses of the step pulley showed especially clearly^[12].

The same book points out that when cutting heavily with high-speed steel cutters, the weakest point is the knee-type table, and introduces Reinecker's surface milling machine, which dropped the knee, set the workpiece on a box-type bed and moved the spindle side up and down along the column^[12]. This is where the machines that move the table up and down (knee type) and those that move the spindle up and down (bed type, gantry type) part ways. Today's horizontal MCs and gantry MCs, which move the spindle side rather than the heavy work on the bed, follow the same idea.

Wanderer's D type: the motor goes into the column

In 1925 Wanderer began developing the D type. According to Stölzel's article, the D type had individual drive by a foot-mounted motor built into the column; it strengthened the column, put every shaft on rolling bearings, and used hardened and ground gears. The mechanism of cams on the table that switch automatically between feed and rapid traverse also first appeared in the company's machines with this type. 900 were built in 1926–30, and from 1932–33 it was called the “D 900”^[7]. Freeing the machine from the overhead line shaft and belts meant that machines on the shop floor could be arranged freely in the order of the work.

In 1926 milling machine production began at the new Siegmar works, and in 1935 Wanderer's milling machine works, with about 1,000 workers making about 1,800 machines a year, became the largest milling machine factory in Europe (the StarragHeckert company history gives 1934)^[7][9]. By 1940 output had risen to about 2,000 a year; besides knee types, the company made thread milling machines, surface milling machines, special milling machines and milling tools. Military demand was a major reason for the increase^[7].

Deckel's patent: horizontal and vertical on one machine

Friedrich Deckel of Munich was a precision mechanic who had worked under Ernst Abbe at Carl Zeiss, and his company had made its name with the “Compur” camera shutter. According to NDB, Deckel began building precision machine tools in 1910, because the precise machines his own factory needed could not be bought^[11].

In December 1932 Deckel filed a patent for combining a milling machine with a horizontal spindle and an angle milling attachment mounted on top (German Patent 665218, published 1938)^[20]. By mounting a head in front of the horizontal spindle that turns the drive through a right angle into a vertical spindle, one machine can cut both horizontally and vertically. It is just the machine for the toolroom, where one-off parts of different shapes, such as dies, jigs and prototypes, are cut. Deckel's universal tool milling machine, which later spread around the world, is built on this idea.

Hydraulics, special-purpose machines and new companies

The interwar years saw the birth of the later leading players. In 1920 five precision workers founded Maho in Pfronten^[13]; in February 1920 Adolf Waldrich founded today's Waldrich Coburg in Coburg^[14]; in 1921 the surgical instrument maker Chiron was founded in Tuttlingen^[15]; in 1923 Karl Hüller founded his company in Ludwigsburg^[16]; in 1926 Ernst Grob founded his in Munich^[17]; and in 1938 Berthold Hermle founded his in Gosheim^[23]. Heller of Nürtingen, founded in 1894, built special milling machines in 1935 to machine the light-alloy crankcases of Messerschmitt's high-speed aircraft, and by 1942 had brought out hydraulic controls, crankshaft milling machines and heavy built-up knee-type milling machines^[8]. In 1936 Waldrich presented its patented hydraulic drive at the Leipzig fair^[14].

In 1944 Wanderer turned out its 25,000th milling machine counting from 1900, but in an air raid in September of that year 60% of the Siegmar works was destroyed^[7][9]. War and the East–West division are covered in Chapter 3.

What it meant on the shop floor. Individual drive by a built-in motor, rolling bearings, ground gears and automatic feed and rapid traverse by cams on the table are all standard equipment on today's manual milling machines. When you come across an old knee-type machine, whether the spindle runs in rolling bearings and whether the feed has a rapid traverse will roughly tell you when it was built.

Rebuilding East and West, tool milling machines and the first NC (1945–1969)

East: from Wanderer to Fritz Heckert

When the war ended, the machines and equipment of Wanderer in Chemnitz were dismantled and carried off by the Soviet occupation forces. According to the description of the Saxon State Archives, this went on from July 6, 1945 to March 1946^[24][7]. Even so, milling machine production resumed at Siegmar in June 1946, and a little over 100 workers turned out 38 machines by the end of the year^[7][9]. On July 1, 1948 the company became people-owned (state-owned), the milling machine division was split off as VEB Wanderer Fräsmaschinenbau, and from 1951 it bore the name Fritz Heckert^[24][7]. In 1960 it became the lead plant of an association of enterprises, and in 1968 the center of the machine tool Kombinat “Fritz Heckert”, which brought together 21 plants and more than 20,000 people^[24][9]; according to a UNIDO report, in the reorganization of the late 1970s it took charge of machines for prismatic (box-shaped) parts^[32]. In the late 1960s the automated machining system PRISMA 2 was born here (the Chemnitz Industrial Museum newsletter says it was developed and installed in the late 1960s; the StarragHeckert company history says it went into operation in 1975)^[33][9].

In the West, in 1948 former Wanderer executives set up a new Wanderer works in Haar near Munich, which built milling machines under the Wanderer name from 1951 until about 1980^[7]. In other words, milling machines with the same name were being built separately in East and West.

West: tool milling machines and swiveling spindle heads

What made West German milling machines known around the world was Deckel's universal tool milling machine. According to NDB, Deckel had 3,000 employees in 1956, and “Deckel precision” had become a set phrase in the world of precision engineering^[11]. Friedrich Wilhelm Deckel and Hans Deckel of the Deckel family filed a patent for a copy milling machine in 1951^[25], and in 1960 a milling head that swivels about the axis of the main drive shaft was the subject of their patent application^[26]. If the center of swivel is aligned with the drive shaft, the drive gears stay in mesh at whatever angle the head is turned. It was a mechanical solution for combining a horizontal spindle and a vertical spindle that could be set at any angle in one machine. Note that the FP1 is not a postwar model: in 1929 a Deckel universal tool milling machine without a model name went on sale in the US, and the name FP-1 appears in an American journal in 1935^[19][21]. The new FP1 of 1937 could be fitted with a swiveling vertical head and a removable swivel table^[22].

Maho in Pfronten, too, began building machine tools for its own use in 1950, and in time took orders for machines built to special specifications^[13]. In 1967 a universal milling machine with a vertical milling head was the subject of a patent application by Werner Babel^[31]. A British journal of 1961 lists four Maho universal tool milling and die-sinking machines, from the MH 600 to the MH 1000^[27]. Hermle in Gosheim began producing milling machines in 1957^[23], and Hüller in Ludwigsburg, besides special-purpose machines and transfer lines (one to Opel in 1953), also built standard machines such as knee-type milling machines from 1954^[16].

Production milling machines, and the first NC and MC

Companies serving automotive mass production took a different path. In 1952 Heller brought out the horizontal production milling machine FH 140. At first a knee type and later a bed type (PF), this machine is regarded by the company as a forerunner of the machining centers of the 1960s. And in 1962 it built an NC milling machine and a machining center with an automatic tool changer^[8]. In 1968 Grob built its first transfer line and a special-purpose machine whose feed lengths could be changed by NC at its new works in Mindelheim^[18]. For the history of NC controls (Siemens' SINUMERIK and the research at Aachen), see Chapter 4.

What it meant on the shop floor. A universal tool milling machine, with a swiveling vertical spindle head and a horizontal spindle, can cut side faces, top faces and angled faces without changing the setup, so it was prized for one-off work on dies and jigs. Checking the swivel scale of the spindle head and the squareness of the spindle after swiveling is the same idea as “calibrating the rotary axes” on today's 5-axis machines.

Machining centers and new ways to change tools (1970–1993)

Automatic tool changing for the toolroom's universal machines

In the 1970s milling machines moved from NC to CNC. Hermle presented its first universal milling machine in 1972, filed a patent in 1973 for a swiveling work table for universal milling machines, and began building NC milling machines in 1975 and CNC ones in 1978^[23][36]. In 1979 a disk-shaped magazine serving as the tool store of a universal drilling and milling machine was the subject of a patent application by Maho^[38]. It was a way of putting automatic tool changing, until then a feature of production MCs, on the universal machines used in the toolroom.

Chiron's basket-type tool changer: no arm

In vertical MCs that cut small parts fast, it was Chiron of Tuttlingen that cut tool change time. The company entered machine tools in 1958 with feed units^[15], and in 1977 filed a utility model for a machine tool with a tool changer^[37]. The tool changer Eugen Rütschle filed for in 1980 used a disk magazine turning on an axis parallel to the spindle, indexed by a cam and moved toward and away from the spindle^[39]. Then in a 1982 filing (U.S. Patent 4,557,035), it took the form in which the tools are arranged in a ring around the spindle, and each holder moves under its own drive onto the spindle axis to hand over its tool. No tool-change arm that grips and carries the tool is needed^[41]. Because the tools surround the spindle like a basket, it is also called the basket type.

Large gantry machines, and production MCs

On the large-workpiece side, Waldrich of Coburg brought out its first NC machine in 1971, delivered a gantry milling machine to the power plant maker Kraftwerk Union in 1973, and in 1975 built a gantry milling machine with a 5,000 mm table width and 18,000 mm clamping length^[14]. H. A. Waldrich of Siegen, after concluding a cross-license agreement with Ingersoll in 1961 under which each built the other's machines^[28][29], was sold to Ingersoll Milling Machine of the U.S. in 1971, and Coburg too joined the Ingersoll group in 1986^[35][14]. So an American company that had led the field in gantry-type planomillers and German makers of large machines became one (for the American Ingersoll, see the American chapter).

On the production side, in 1982 Heller fitted its own CNC (uniPro NC 80) to its BEA machining centers and began volume production^[8], and Grob built its first MC in 1977 and began developing the BZ series in 1983^[18]. In the Hüller Hille group, formed in 1975 under Rheinstahl (later Thyssen), Maschinenfabrik Diedesheim of Mosbach devised the PROCASS PC 601 cassette tool magazine in 1984 and delivered a flexible machining system to Opel^[16]. In 1984 Kern, a contract maker of precision parts, put into operation a CNC micro-drilling and milling machine accurate to the 0.001 mm range that it had built for itself, and became a machine tool maker too^[30].

Competition with Japan, and Deckel and Maho in trouble

In this period German milling machines ran head-on into Japanese MCs. According to Anderson Ashburn, a former editor of an American trade magazine, 200 companies showed MCs at the 1981 machine tool show in Hannover, and the technical lead of the Japanese exhibitors shocked the German industry. At the 1985 show (160 companies), Ashburn writes, Germany, which had kept up research and development even while losing money, seemed to have regained the lead^[40]. In UNIDO statistics, the share of MCs in the 1988 production value of milling-type machines was 81% in Japan and 39% in West Germany^[32]. The figures show that Japan moved to MCs all at once, while Germany went on making both universal milling machines and MCs.

A 1990 UNIDO report named Deckel as West Germany's largest machine tool maker, and reported that one cause of its slump was that it had put too much weight on NC and lost its long-standing small and medium-sized customers, who found the new technology difficult^[32]. In 1990, the year of reunification, the eastern works in Seebach (built around 1970, making universal milling machines and drilling machines) began cooperating with Maho^[34], and Heckert in Chemnitz became a company under the Treuhand, built the CWK series of MCs in 1992, and was then bought by Traub in 1993^[9]. In 1989 Maho filed a patent for the nozzle head of a machine that engraves with a laser the way a milling cutter cuts — a “laser milling machine”^[43].

What it meant on the shop floor. An arm-type tool changer can handle large tools, but it makes many moves and takes time. Basket-type and direct-from-magazine changers are limited in tool size and number, but they are fast, and they greatly cut the “chip-to-chip” time on small mass-produced parts. Many of today's compact vertical MCs and tapping centers belong to this line.

★5-axis machines and consolidation (1994–)

The birth of DMG

In the early 1990s Deckel and Maho, by then merged as Deckel Maho, went bankrupt, and in 1994 the Bielefeld lathe maker Gildemeister took over most of it^[5][13]. Gildemeister, founded in 1870, was a company of automatics and lathes^[5], and so “DMG” was formed, combining Gildemeister in lathes and Deckel Maho in milling machines. Gildemeister's 2007 annual report tells of volume production of the compact 5-axis DMU 40 monoBLOCK starting in Pfronten, and of a spiral bevel gear being finished on a single machine, the DMC 125 FD duoBLOCK with simultaneous 5-axis control^[47]. The line of Deckel and Maho, which began with universal milling machines for the toolroom, had arrived at the 5-axis machine that moves a swiveling table and spindle head by NC.

Where to put the rigidity: Hermle and Grob

In the 5-axis era, German makers competed on the machine's framework. In 1994 Hermle filed a patent for a structure in which the longitudinal slide is supported on three rails, on top of the bed's left and right walls and a third rail placed between them, and driven in the middle. The explanation is that even when twisted by off-center forces, the force acts at right angles to the guides and is easier to take up^[44]. Placing the machining area between the bed's left and right walls, and moving the upper slide rather than the table, is close to the idea of the gantry type.

In 1996 Grob filed a patent for placing the table on the pallet and cutting the workpiece hanging down from the pallet in a machining center^[45]. Chips do not pile up on the work or fixture but fall away. It brought out the linear-motor BZ600L in 1998, the modular G-Module in 2004 (1,000 units in under three years) and the 5-axis universal machine G350 in 2007^[18]. Heller brought out the 4-axis horizontal H series in 2007, the 5-axis F series in 2009 and the HF series in 2016^[8].

Ultra-precision, and the fate of the large machines

In 2005 Kern supported each axis on hydrostatic bearings (floating on a film of oil) in its new ultra-precision Pyramid Nano^[46][30]. With guides that neither roll nor slide, it reduces friction and wear and aims at surfaces in the nanometer range. On the large-machine side, the bankruptcy of the American parent Ingersoll led to the sale of Waldrich Coburg and Waldrich Siegen to the Herkules group in 2004, and Coburg came under Beijing No.1 Machine Tool in 2005^[14][35]. Schiess of Düsseldorf merged with the eastern works in Aschersleben after reunification, and came under Shenyang of China in 2004 and China's Longma in 2019^[1]. Heckert in the East was bought by Starrag of Switzerland in 1998 and became StarragHeckert in 2000^[9].

On to DMG MORI

In 2009 DMG (Gildemeister) and Japan's Mori Seiki formed a capital and business alliance, and in 2013 Mori Seiki changed its name to DMG MORI^[48]. Under a domination and profit transfer agreement of June 2, 2016, Germany's DMG MORI AKTIENGESELLSCHAFT is part of the group of Japan's DMG MORI^[6]. Today Pfronten (formerly Maho) employs about 1,600 people making 50 types of milling machines and MCs^[13], and Seebach in the East is responsible for developing and building the 5-axis DMU 50^[34]. In 2026 DN Solutions of Korea bought Heller (according to Heller's company history)^[8].

What it means on the shop floor. When choosing a 5-axis machine, look at whether the table or the spindle head swivels, how the guides that carry the slides are arranged, which way the chips fall, and whether the axes are hydrostatic or linear-motor driven; that tells you whether the machine is strongest at heavy roughing, fast finishing, volume production or ultra-precision work. The basics of 5-axis work are covered in the 5-axis machining pages.

Links with Japan

German and Japanese milling machines and MCs have faced each other as rivals since the 1980s. As seen above, Japanese MCs shocked the German industry at the Hannover show (1981), Germany fought back through research and development (1985), and in 1988 MCs made up 81% of Japan's milling-type production against 39% in West Germany^[40][32]. The story of Japanese MCs is told in Japanese Archive, Chapter 2, and 5-axis and multitasking machines in Chapter 7.

In time, the rivals became one group. Through the 2009 alliance between DMG and Mori Seiki, the 2013 renaming to DMG MORI^[48] (timeline of Chapter 1 of the Japanese archive), and the 2016 domination agreement over DMG MORI AG^[6], the milling machines descended from Deckel and Maho became machines of a Japanese company's group. Grob of Mindelheim also opened a base in Yokohama in 2019^[17].

FAQ

Who built the first milling machine in Germany?

The earliest case whose year can be confirmed in a biographical dictionary is J. E. Reinecker of Chemnitz. According to NDB, in 1872 he began building milling machines, grinding machines and relieving lathes on the American model. Woodbury's book also mentions a Reinecker machine of 1867. Before that, German factories imported or copied American milling machines.

What kind of companies were Deckel and Maho, and what has become of them?

Deckel (1903, Munich) moved from camera shutters into precision machine tools and was known for its universal tool milling machine, which combined horizontal and vertical spindles in one machine. Maho (1920, Pfronten) also went from universal milling machines to CNC machines. The two merged in the early 1990s, and in 1994 Gildemeister took them over to form DMG. Today they are part of DMG MORI, and the Pfronten works still builds milling machines and MCs.

What is Chiron's “basket-type” tool changer?

The tools are arranged in a ring around the spindle, and each tool holder moves under its own drive to just below the spindle to hand over its tool. With no tool-change arm needed to carry the tools, changes are faster. Chiron filed a patent for a tool changer with a magazine in 1980, and for this form in 1982.

What became of the East German milling machine makers?

After the war, Wanderer's milling machine division in Chemnitz became the state-owned VEB Fritz Heckert, and from 1968 it was the center of a machine tool Kombinat. After reunification it became a company under the Treuhand, was bought by Traub in 1993, became a new company after the 1996 bankruptcy, and in 1998 was bought by Starrag of Switzerland to become StarragHeckert. The eastern works in Seebach cooperated with Maho and is today DMG MORI's 5-axis machine plant.