Metal cutting processes are industrial processes in which metal part are shaped by removing unwanted material from a blank (material input).
Woodworking tools like the cord lathe and the bow drill were in existence in ancient times. They used kinematic motions which are now used in several machine tools.
Leonardo Da Vinci drew designs for number of machine tools but they were not actually produced.
The first large metal cutting machine tools based on water power were cannon boring mills built in Italy in the early 1500s.
The first scientific study of metal cutting was done cannon boring and was reported by Count Rumford in a paper presented in 1798 to the Royal Society in London.
The Steam Engine - The Industrial Revolution and Further Development of Machine Tools
The development of steam engine led to the further development of machines powered by steam.
It stimulated the development of many basic machine tools, since these were required to produce
the precise cylinders, surfaces of revolution, screw threads, and flat surfaces integral to the function
of the new machinery. Machine shops now could be built at any convenient location as they are run n steam power. The bulk of the significant early machine tool development took place in England, although other parts of Europe have taken part in it.
Boring Mill
John Wilkinson invented a more accurate horizontal boring mill in 1775. Wilkinson used a much heavier boring bar than was used in cannon boring mills, and supported the bar at both ends, greatly increasing rigidity and accuracy. He also used cutters with replaceable inserts driven by a feed screw inside the bar. This machine was the first recognizably modern machine tool, since it could perform heavy cuts with reasonable accuracy and employed a basic design that was replicated into the late twentieth century. Machine tools with the same basic layout are still widely used for line boring and large diameter work.
Lathes
Heavy metal cutting lathes came into use in the eighteenth century for machining rolling
mill rolls and cylinders for automatic looms. The design ancestral to later screw-cutting engine
lathes, however, was developed by Henry Maudslay (1771–1831) in England. His screw-cutting lathe was built around 1797, employed Vee ways and a slide rest driven from a lead screw to cut threads. Maudslay set new standards of accuracy for the profession by inventing a bench micrometer and pioneering the use of surface plates. He also trained many of the leading machine builders of the day, most notably Joseph Whitworth, who standardized screw threads, developed many feed and drive mechanisms, and was among the first to appreciate the primary importance of structural rigidity in machine tool design.
Planers and Shapers
Drilling Machines
Drilling was typically performed on boring mills or lathes in early days. Upright and radial drill presses were introduced later. Among the earliest were the upright or pillar drill presses introduced by Bodner and Whitworth in England in 1839 and 1847, respectively. A similar machine was patented in Germany in 1849 by August Harmann.. Radial drill presses were built in England in the early 1840s and a radial drill press was developed and marketed in Germany by Johann Mannhardt in 1848. American quantity production firms soon recognized that multiple drilling spindles could be ganged together on a common base to produce multispindle machines for rapidly and accurately drilling hole patterns. These gang drill presses were used especially in the railroad industry for drilling hole patterns in boilers and wheels. The twist drill was patented by Stephen A. Morse in 1863. This now-ubiquitous tool rapidly displaced the crude spear-point drill used until that date.
Grinding Machines
Woodworking tools like the cord lathe and the bow drill were in existence in ancient times. They used kinematic motions which are now used in several machine tools.
Leonardo Da Vinci drew designs for number of machine tools but they were not actually produced.
The first large metal cutting machine tools based on water power were cannon boring mills built in Italy in the early 1500s.
The first scientific study of metal cutting was done cannon boring and was reported by Count Rumford in a paper presented in 1798 to the Royal Society in London.
The Steam Engine - The Industrial Revolution and Further Development of Machine Tools
The development of steam engine led to the further development of machines powered by steam.
It stimulated the development of many basic machine tools, since these were required to produce
the precise cylinders, surfaces of revolution, screw threads, and flat surfaces integral to the function
of the new machinery. Machine shops now could be built at any convenient location as they are run n steam power. The bulk of the significant early machine tool development took place in England, although other parts of Europe have taken part in it.
Boring Mill
John Wilkinson invented a more accurate horizontal boring mill in 1775. Wilkinson used a much heavier boring bar than was used in cannon boring mills, and supported the bar at both ends, greatly increasing rigidity and accuracy. He also used cutters with replaceable inserts driven by a feed screw inside the bar. This machine was the first recognizably modern machine tool, since it could perform heavy cuts with reasonable accuracy and employed a basic design that was replicated into the late twentieth century. Machine tools with the same basic layout are still widely used for line boring and large diameter work.
Lathes
Heavy metal cutting lathes came into use in the eighteenth century for machining rolling
mill rolls and cylinders for automatic looms. The design ancestral to later screw-cutting engine
lathes, however, was developed by Henry Maudslay (1771–1831) in England. His screw-cutting lathe was built around 1797, employed Vee ways and a slide rest driven from a lead screw to cut threads. Maudslay set new standards of accuracy for the profession by inventing a bench micrometer and pioneering the use of surface plates. He also trained many of the leading machine builders of the day, most notably Joseph Whitworth, who standardized screw threads, developed many feed and drive mechanisms, and was among the first to appreciate the primary importance of structural rigidity in machine tool design.
Planers and Shapers
Textile machinery, steam locomotives, and commercially produced machine tools required accurately machined flat surfaces, which led to the development of planers and shapers in the early nineteenth century. Both planers and shapers produced flat surfaces by moving a tool over a workpiece in a series of parallel and overlapping strokes. In a planer, the tool remained stationary and the workpiece, generally fixed to a table, moved relative to it; in a shaper, the work was stationary and the tool moved, generally on some sort of bar or arm. Planers were used almost exclusively to produce flat surfaces, since the moving table was heavy and difficult to maneuver along a contour. Shapers, on the other hand, could be readily adapted to produce shaped features such as slots, keyways, and straight gear teeth. A number of planers were built in England before 1825, notably by Richard Roberts, James Fox, and Joseph Clement. Among the first to be developed was Naysmith’s steam arm shaper, built about 1836. In this machine, the tool was mounted to a ram driven by a connecting rod. This was a common design during the nineteenth century, although traveling head machines of the type designed by Whitworth between 1840 and 1850, in which the tool was mounted on a head driven by reversing screws, were also prevalent.
Milling Machine
Simple milling methods had already been developed by Vaucanson in France and Naysmith in England. Small arms makers in Connecticut also reportedly constructed simple milling machines by 1820. The oldest extant machine was dated to 1818 and attributed to Eli Whitney even though the attribution is questioned. The first commercially produced milling machine was the Lincoln Miller ,
designed by F. A. Pratt and E. K. Root and marketed by George S. Lincoln and Co. in 1855. Pratt’s new company, Pratt and Whitney, began manufacturing them in large quantities later. Brown and Sharpe’s universal miller was designed by J. R. Brown and introduced in 1862. This machine featured a knee and column structure, which greatly simplified the adjustment of the work height and is the design of choice of the familiar knee-mill of twentieth-century practice.
Milling Machine
Simple milling methods had already been developed by Vaucanson in France and Naysmith in England. Small arms makers in Connecticut also reportedly constructed simple milling machines by 1820. The oldest extant machine was dated to 1818 and attributed to Eli Whitney even though the attribution is questioned. The first commercially produced milling machine was the Lincoln Miller ,
designed by F. A. Pratt and E. K. Root and marketed by George S. Lincoln and Co. in 1855. Pratt’s new company, Pratt and Whitney, began manufacturing them in large quantities later. Brown and Sharpe’s universal miller was designed by J. R. Brown and introduced in 1862. This machine featured a knee and column structure, which greatly simplified the adjustment of the work height and is the design of choice of the familiar knee-mill of twentieth-century practice.
Drilling Machines
Drilling was typically performed on boring mills or lathes in early days. Upright and radial drill presses were introduced later. Among the earliest were the upright or pillar drill presses introduced by Bodner and Whitworth in England in 1839 and 1847, respectively. A similar machine was patented in Germany in 1849 by August Harmann.. Radial drill presses were built in England in the early 1840s and a radial drill press was developed and marketed in Germany by Johann Mannhardt in 1848. American quantity production firms soon recognized that multiple drilling spindles could be ganged together on a common base to produce multispindle machines for rapidly and accurately drilling hole patterns. These gang drill presses were used especially in the railroad industry for drilling hole patterns in boilers and wheels. The twist drill was patented by Stephen A. Morse in 1863. This now-ubiquitous tool rapidly displaced the crude spear-point drill used until that date.
Grinding Machines
Prior to 1850, cylindrical and surface grinding machines were used especially for grinding rifle barrels, hardened slides for steam engines, and pulleys and rollers for automatic machinery. Many early cylindrical and surface grinders were basically modified lathes or planers fitted with abrasive wheels. Early grinders generally used natural stone wheels or natural emery abrasives embedded in leather or wooden wheels. The development of precision grinders began after 1860. In 1876, Brown and Sharpe, an early contract manufacturer of sewing machines, brought out a universal grinder, which had the basic form of later cylindrical grinders and was also followed in surface grinders of similarly modern form by 1883. These influential machines were sold worldwide beginning in the 1880s. Bonded aluminum oxide and silicon carbide wheels became available between 1885 and 1910 and made grinding more productive.
Gear Cutting Machines
Between 1825 and 1840 several English machine tool builders built form-cutter-type gear machines based on the milling principle. Whitworth introduced involute cutters about 1844. Templet machines, in which the teeth were cut with a shaper or slotter tool guided by a template were developed and were especially popular for large gears. The development of precision grinding permitted manufacture of accurate complex tooling from hardened steel. The Fellows gear shaper and hobbing machines are products of the 1890s.
Gear Cutting Machines
Between 1825 and 1840 several English machine tool builders built form-cutter-type gear machines based on the milling principle. Whitworth introduced involute cutters about 1844. Templet machines, in which the teeth were cut with a shaper or slotter tool guided by a template were developed and were especially popular for large gears. The development of precision grinding permitted manufacture of accurate complex tooling from hardened steel. The Fellows gear shaper and hobbing machines are products of the 1890s.
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