ARCHIVE 05The Lineage of Drilling and Boring Machines

Making Drilling Machines in Japan and the First Horizontal Boring Machines (1881–1926)

In the early Meiji era almost all machine tools were imported, but drilling machines were also being made in government factories. The product catalog Seizo kikai-hin (Manufactured machinery), published in 1881 by the Ministry of Public Works' Akabane Engineering Works, lists machine tools such as a "sanko kikai" (hole-drilling machine), the equivalent of an upright drilling machine^[1]. In the private sector, Ikegai delivered lathes of its own make to the Naval Engineering College in 1898, and from then on received orders for drilling machines, along with lathes and planers, from various navy departments^[2].

Branch-type drilling machine: the first import of foreign technology

In 1912 Rokuroku Sangyo used technology it had acquired in the US to build a branch-type drilling machine in Japan. The National Museum of Nature and Science's Industrial Technology History Database calls this a landmark event that can be considered the first introduction of foreign technology for Japanese machine tools, and says this design became the standard for drilling machines and was built until recent years. The No. 1 machine still survives at the company^[3]. In the Taisho era Okuma Iron Works also came to build most of the main general-purpose machines besides lathes, including drilling machines, grinders, boring machines and milling machines^[1].

Gun barrel lathes and the first large horizontal boring machine

Machines for cutting large holes began with cannon and large machinery. In 1915 Karatsu Iron Works completed a gun barrel lathe that could both turn and bore on one machine^[4]. Among the noteworthy machines Niigata Engineering built around 1922 and 1924, its company history lists a 7-inch horizontal boring machine (weighing 30 tons) delivered to Hitachi^[5]. The size of a horizontal boring machine is given by the diameter of its spindle (boring bar); 7 inches is about 180 mm.

Early Showa: Jig Borers Arrive (1926–1937)

Prompted by the 1921 Machine Tool Exhibition, the Society of Mechanical Engineers set a standard for drilling machines in 1929, following the one for lathes in 1926^[1]. In mass-production plants, special machines for drilling and boring were devised. In 1927, to mass-produce the Type G automatic loom, Toyoda Automatic Loom Works drilled iron and cast parts on drilling machines (made by Mitsubishi Electric, according to the database), and also built a special-purpose three-spindle simultaneous boring machine that bored the three bearing holes and machined both sides of the assembled loom frame in a single pass. The hole centerlines lined up, improving accuracy and assembly efficiency^[6][7]. In 1929 the forerunner of Yasda was founded in Osaka and began boring automobile engine cylinders (the company calls this "the first in Japan")^[8].

Jig borers

A jig borer is a machine that bores holes in jigs and dies with the table positioned extremely accurately. Jig borers came to Japan in the 1930s. In 1936 Kikai Gakkai-shi (Journal of the Society of Mechanical Engineers) introduced a jig borer by Lindner of Germany as "a cutting-edge precision machine" that read positions with a microscope^[9]. The Nippon Institute of Technology Museum of Industrial Technology has a jig borer of a type that SIP of Switzerland began making in 1931; it is said to be the first machine of this type imported into Japan^[10].

Wartime: Japanese Jig Borers and Gun Barrel Boring Machines (1938–1945)

The Machine Tool Manufacturing Industry Act of 1938 gave special support to companies making precision machines. For companies making automatic, special-purpose and high-precision machines "specified by ordinance", such as precision bench drilling machines and jig borers, the licensing requirement was lowered to 50 machine tools in their plant (200 in general), and jig borers and fine boring machines were also among the items eligible for prototype subsidies^[11]. Okuma Iron Works, which became a licensed company in July of the same year, 1938, listed boring machines and radial drilling machines among its main products^[11].

1938: Japan's first jig borers

Toyo Seiki (today's Mitsui Seiki Kogyo), which became a licensed company in the same month, began producing the jig borer (Type 4). The company's history calls it "Japan's first jig borer"^[12]. The company's 1943 jig borer at the Nippon Institute of Technology Museum of Industrial Technology was modeled on an SIP machine from Switzerland; about 220 were built from 1938 to the end of the war, and it is said to have become the mother machine of the precision machinery industry^[10]. As for SIP's own machines, a Type MP-4G built in 1939 was imported and then, on navy orders, transferred to a private maker, where it was used to raise the level of Japanese technology^[14].

A note on company names. Mitsui Seiki Kogyo was founded in 1928 as "Tsugami Seisakusho", became Toyo Seiki in 1937, and merged with Mitsui Kosakuki in 1942 to become Mitsui Seiki Kogyo (according to the company's history)^[12]. It is a different company from the Tsugami Seisakusho founded in Nagaoka, Niigata Prefecture in 1937 (today's Tsugami; see Chapter 1)^[34].

Gun barrel boring machines

Boring machines that cut the long bores of gun barrels were the archetypal large machines of wartime. In 1938 Karatsu Iron Works completed an extra-large gun barrel boring machine for the main guns of the battleships Yamato and Musashi and delivered it to the Kure Naval Arsenal. The company's history gives its overall length as about 64 m^[4]. Shibaura Kosaku Kikai (today's Shibaura Machine), founded in December 1938 with investment from Shibaura Engineering Works,^[13] built special boring machines in 1939 and 1941 and delivered them to the Yokosuka Naval Arsenal (machining guns and bombs), the Harima and Osaka Army Arsenals (boring gun barrels) and elsewhere^[11].

Precision boring machines: aircraft and automobile engines

Also made in Japan from this period on was the precision boring machine, which finishes engine cylinders and bearing bores accurately in mass production. Toyoda Machine Works, founded in 1941, applied to produce multi-spindle special drilling machines, precision boring machines and other types that existing machine tool companies had not been building^[11], and its Type EJ/ES precision boring machines were used to mass-produce aircraft parts during the war and automobile parts after it^[15]. In January 1941, as types designated under the National Mobilization Law, Niigata Engineering built the Type 9Fb precision boring machine, modeled on a machine by Krause of Germany, and gun barrel boring machines^[5]. Ikegai Iron Works also built a prototype Type FBI precision boring machine in 1942, making accessories such as electrical equipment, oil pumps, clutches and gauges together with specialist Japanese suppliers^[11].

Postwar: Radial Drilling Machines, Jig Borers and Large Horizontal Boring Machines (1945–1964)

In the postwar rebuilding, government subsidies encouraged new types of machines. Machine tool import subsidies were granted in 1952, and from 1953 machine tool prototype subsidies were granted every year^[16]. The 1950s subsidy lists include hydraulic radial drilling machines, jig borers, precision horizontal boring machines, inclined multi-spindle precision boring machines, hydraulic optical jig borers, and "research prototypes of optical jig borers and jig grinders"^[16].

More precise jig borers

In March 1955 Mitsui Seiki Kogyo began making its No. 3 jig borer, which received the first Akashi Memorial Award of the Japan Society of Precision Engineering^[12]. In the 1963 Kokusan kosaku kikai sogo katarogu (Comprehensive catalog of Japanese machine tools), the company presented its optical jig borers, Types No.3 and No.5, as drawing on "25 years of rich experience in building jig borers"^[23] (25 years from 1938). From 1956 the government's Mechanical Engineering Laboratory thoroughly studied the structure and performance of the SIP jig borer brought in during the war, and in 1959 exhibited the numerically controlled jig borer JIDIC at a trade fair^[14][20] (Chapter 2). Yasda, which had started out boring cylinders, developed the horizontal precision boring and milling machine "Jig Master" in 1964, bringing jig borer precision to a horizontal machine^[8].

Radial drilling machines and drilling machine makers

Radial drilling machines, used for drilling large workpieces, also became faster and more accurate. Okuma Iron Works' Type DRA-J high-speed heavy-duty radial drilling machine of 1958 was stiffened to allow jig-borer-level precision drilling and high-speed machining, and could be set up for the next cutting conditions while machining; more than 3,000 were sold^[18]. In the radial drilling machine section of the 1963 catalog, Osaka Kiko's Type DRB-17 and others appear alongside the Type DRA-J^[23]. Small drilling machines were made by many small and medium-sized companies; even in figures from the early 1960s, vertical drilling machines were the one type with a high share of makers outside the Japan Machine Tool Builders' Association^[11]. In Aichi Prefecture, Mikawa Nainenki Kogyo began making bench drilling machines and tapping machines in 1956, changed its name to Kira Iron Works in 1957, and released an upright drilling machine in 1958 (today's Kira Corporation)^[17].

Boring tools were also made in Japan. Around 1958, on MITI's advice, Kuroda Precision Industries began making universal boring heads, which had been expensive imports, and in 1962 made them into the UFB-3 series. They allowed boring and facing on ordinary milling and drilling machines, and supported machining work until machining centers became widespread^[22].

Large horizontal boring machines: Mitsubishi Innocenti and Toshiba Machine

Machining large box-shaped parts for power-plant turbines, marine diesel engines, railway vehicles and the like requires large horizontal boring machines. In 1959 Mitsubishi signed a technical tie-up with Innocenti of Italy for a large combined milling and boring machine designed by C.W. Berthiez of France, and began building it at Hiroshima Seiki Seisakusho. From 1960 it was sold as the "Mitsubishi Innocenti CWB combined milling and boring machine" (MIB machine); called "a revolutionary among large machine tools", 122 had been built by October 1968^[19][21]. In JMTBA figures from the early 1960s, Toshiba Machine and Ikegai competed in horizontal boring machines, while Shin Nippon Koki made more than 70% of precision boring machines^[11]. The horizontal boring machine section of the 1963 catalog lists Shin Nippon Koki, Toshiba Machine, Ikegai Tekko, Wakayama Iron Works, Karatsu Iron Works and others^[23].

Toward NC and Horizontal Machining Centers (1965–1993)

Drilling and boring machines machine holes with the table stopped at set positions, so they can be run by "positioning" NC, which moves the table step by step and stops it. The 1968 catalog also lists Toshiba's NC unit as one for positioning the tables of drilling and boring machines^[26].

NC drilling machines

In 1965 Rokuroku Sangyo, together with Fujitsu (whose NC division later became FANUC), built the tape-controlled automatic drilling machine 501-HANC and delivered it to the University of Yamanashi. It was the company's first NC machine, and the National Museum of Nature and Science database speculates that it "may have been Japan's first NC drilling machine". The next year it evolved into the SS-55 printed circuit board drilling machine^[24]. The 1968 mass-production NC drilling machine RND-1003 had a highly rigid structure with a box-shaped bed, column and spindle head, said to have become the basic form of later vertical machining centers. Up-and-down (Z-axis) motion was controlled by limit switches instead of expensive NC, and the feed was interrupted to break the long chips from the drill, among other ideas^[27].

JMTBA's 1968 catalog of NC machine tools has a section for numerically controlled drilling machines (Ikegai Tekko, Rokuroku Sangyo and others) and one for numerically controlled boring machines, the latter listing Ikegai Tekko's numerically controlled horizontal milling and boring machine, Toshiba Machine's Type BFT table-type horizontal boring and milling machine, Nomura Seisakusho's NB-100, and Mitsui Seiki's optical jig borers with numerical control, the 4BN, 6BN and 7AN^[26].

The MAF machine: Japan's first NC boring and milling machine

As the successor to the MIB machine, Mitsubishi Heavy Industries completed the first of its in-house "Mitsubishi combined milling and boring machine", the MAF machine, in November 1967. Built to meet the growing size of shipbuilding and nuclear machinery, it is called by the company "Japan's first NC boring and milling machine". It was a large horizontal boring combination machine for machining turbine casings, with a total weight of 320 tons. In 1971 it was designated the first domestically developed machine under the heavy machinery development program, and in 1972 it received the Japan Society for the Promotion of Machine Industry Award^[19][21][25]. In 1983 came the MAF machine RS series, CNC horizontal boring and milling machines with an ATC, automatic attachment changing and a large pallet changer^[19], and in 1986 the company built the "Super Miller", an extra-large NC combined milling machine with a 13 m width between columns and a total weight of 1,300 tons (the company calls it one of the largest in the world)^[25][21].

From horizontal boring machines to horizontal machining centers

Add an automatic tool changer (ATC) and an indexing table to a horizontal boring machine and you get a horizontal machining center that can machine four sides of a box-shaped part in one setup. The jig borer and boring machine companies went straight on to become MC companies. Mitsubishi Heavy Industries completed the Diamatic MPA series in 1968 (the company regards it as a pioneer of Japanese MCs)^[21], and in October 1970 Mitsui Seiki Kogyo began producing its first MCs, the Jidic H5B and H6B^[12]. Okuma Iron Works began building the horizontal MC MC-H in 1980^[29], and Kira Iron Works, the drilling machine maker, began making and selling MCs in 1981^[17].

For drilling on mass-production lines, the four-spindle fully automatic turret drilling machine released around 1975 by Takeda Kikai of Fukui automatically performed center drilling, pilot drilling, chamfering and tapping in sequence, pioneering the replacement of the special-purpose machines used for drilling on automotive and home-appliance parts lines with inexpensive general-purpose machines^[28].

★Today (1994–)

Many of the jig borer and horizontal boring machine companies carry on as makers of machining centers and large multitasking machines. Yasda's Jig Master YBM50J-S received the Best Technical Award in 2007 under the Nippon Institute of Technology Museum of Industrial Technology's "Recognition of Machine Tools of Historical Value"^[8].

Company names changed too. Kira Iron Works became Kira Corporation in 1994 through a merger of three group companies^[17], Toshiba Machine became Shibaura Machine in 2020^[13], and Mitsubishi Heavy Industries' machine tool business was split off as Mitsubishi Heavy Industries Machine Tool in 2015 and came under Nidec in 2021 (today's Nidec Machine Tool)^[30]. Karatsu Iron Works changed its name to Karatsu Precision in 2016^[4]. Today's makers of drilling machines and machining centers are listed in Machine Tool Makers.

What it means on the shop floor. When looking at a used drilling or boring machine, check "the spindle diameter (the size designation of a horizontal boring machine)", "how the table position is read (screw and dial, optical scale or NC)", "the type of spindle taper" and "whether the feed is manual or automatic". These tell you the machine's generation and how accurate a hole you can trust it with.