The world's first true boring machine was born like this!

　　What is a boring machine? A boring machine is a machine tool that uses a boring bar to bore holes in a workpiece, as shown in the figure below. Typically, the boring bar rotates as the main movement, and the movement of the boring bar or workpiece is the feed movement. Its machining accuracy and surface quality are higher than that of a drilling machine. Boring machines are the main equipment for machining large box-shaped parts.

　　How much do you know about the history of boring machines? Today, let's take a look at how the world's first true boring machine was born.

　　Boring Machine

　　Before looking at the first boring machine, let's see what parts are mainly processed by a boring machine. The main function of a boring machine is to bore various holes and hole systems on workpieces, especially suitable for processing multi-hole box-type parts (see the figure below). In addition, it can also process planes and grooves.

　　Box-type Part

　　In the long history of human development, through persistent efforts, we have achieved innovation and progress time and again. Let's find the inventor of the world's first true boring machine together!

　　The Earliest Boring Machine

　　Leonardo di ser Piero da Vinci (1452-1519) was an Italian Renaissance painter, scientist, and symbol of human wisdom. He was the most famous artist of the Italian Renaissance. He was not only a great painter, but also a futurologist, architect, mathematician, musician, inventor, anatomist, sculptor, physicist, and mechanical engineer. He was known for his superb painting skills. At the same time, he also designed many inventions that were impossible to realize at that time but have appeared in modern science and technology.

　　In the 15th century, due to the need to manufacture clocks and weapons, there appeared clockmaker's screw-cutting lathes and gear processing machine tools, as well as water-driven cannon boring machines. In 1501, Da Vinci drew conceptual sketches of lathes, boring machines, screw processing machine tools, and internal grinders, which already included mechanisms such as cranks, flywheels, centers, and bearings.

　　The boring machine is known as the "mother of machinery." Speaking of boring machines, we have to talk about Da Vinci. This legendary figure may be the designer of the earliest boring machine used for metal processing. The boring machine he designed used water power or foot pedals as power. The boring tool rotated close to the workpiece, while the workpiece was fixed on a moving platform driven by a crane. In 1540, a Chinese painter painted a painting called "Firework Technology", which also shows a similar boring machine, as shown in the figure. This is similar to modern boring processing, using a special grinding wheel (tool) to gradually grind away the inner jade. At that time, the boring machine was specifically used for the fine processing of hollow castings.

　　Boring in "Firework Technology"

　　John Smeaton designed and manufactured a special machine tool for cutting the inner circle of a cylinder.

　　Smeaton was one of the best mechanical engineers of the 18th century. When he was a child, Smeaton was very interested in machinery. When he went to school, he became even more enthusiastic about lathes, steam engines, and other machinery, and he made and assembled models of these machines himself, showing the qualities of a mechanical engineer at a very young age. After graduating from school, John Smeaton decided to work for a lawyer. After working as a lawyer for about three years, he gave up his job as a lawyer because he was very interested in the rapidly developing mechanical technology at that time.

　　John Smeaton wanted to become a true precision mechanic, so he went to work in a factory that manufactured scientific instruments and mathematical instruments. At that time, Britain was in a period of rapid development, with industrial development advancing by leaps and bounds, and projects such as transportation, coal mining, and harbor construction were all proceeding smoothly. Various machines needed for production and construction were also being manufactured one after another.

　　Previously, when John Smeaton saw the use of a Newcomen atmospheric steam engine to drive a drainage pump in a coal mine near his home in Yorkshire, he became very interested in this large device, which is also the reason why he later made a steam engine.

　　For a considerable period of time after the death of the atmospheric steam engine maker Newcomen, "theorists" did not pay attention to this machine. The development of Newcomen's atmospheric steam engine depended on practical workers. The earliest mechanical engineer to show great interest in steam power and to begin to improve it was Smeaton.

　　When making steam engines, the most difficult thing for Smeaton was processing the cylinder. It was quite difficult to process the inner circle of a large cylinder into a circle. To this end, Smeaton made a special machine tool for cutting the inner circle of a cylinder at the Carron Ironworks. This boring machine was driven by a water wheel, and a tool was installed at the front end of its long shaft, which could rotate inside the cylinder to process its inner circle. Because the tool was installed at the front end of the long shaft, problems such as shaft deflection would occur, so it was very difficult to process a truly circular cylinder. To this end, Smeaton used the method of changing the position of the cylinder many times for processing. Later, Wilkinson improved this boring machine and accurately processed the inner circle. By improving the processing accuracy, Smeaton more than doubled the efficiency of the Newcomen atmospheric steam engine.

　　The world's first true boring machine was born.

　　John Wilkinson, a British inventor and the inventor of the world's first true boring machine (i.e., cannon boring machine) (see figure).

　　John Wilkinson

　　When Wilkinson was 20 years old, his family moved to Staffordshire. He built the first ironworks in Bilston, so he was called "the master blacksmith of Staffordshire". In 1774, at the age of 47, Wilkinson finally manufactured a new machine capable of drilling large cannon barrels with rare precision in his father's factory. Interestingly, after Wilkinson's death in 1808, he was buried in a cast iron coffin of his own design. By the 17th century, due to military needs, the development of cannon manufacturing was very rapid, and how to manufacture cannon barrels became a major problem that people urgently needed to solve. After Watt obtained the patent for the practical steam engine in 1769, the processing accuracy of the cylinder became a key issue for the steam engine.

　　Wilkinson's boring machine, invented in 1774, played a great role in solving these problems. To be precise, Wilkinson's boring machine was a machine that could precisely process the bore of a cannon. It was a hollow cylindrical boring bar with bearings installed at both ends, as shown in the figure. The cylinder bored by this cannon boring machine also met the requirements of Watt's steam engine. In 1775, the world's first true boring machine was born.

　　Gun barrel boring machine diagram

　　In 1776, Wilkinson manufactured a relatively precise waterwheel-driven cylinder boring machine, as shown in the figure below. This machine uses a waterwheel to rotate the material cylinder and advances it towards a centrally fixed tool. Due to the relative movement between the tool and the material, a highly precise cylindrical hole is bored into the material. The invention of the boring machine promoted the development of the steam engine. From then on, machine tools began to be driven by steam engines via crankshafts.

　　Cylinder boring machine

　　However, Wilkinson's invention was not patented, and people copied and installed it. In 1802, Watt mentioned Wilkinson's invention in his book and copied it in his Soho ironworks. Later, Watt also used Wilkinson's amazing machine in the manufacture of steam engine cylinders and pistons. For pistons, it was possible to measure the dimensions and cut them on the outside, but it was not so simple for cylinders, and a boring machine was essential. At that time, Watt used a waterwheel to rotate the metal cylinder, allowing the centrally fixed tool to advance to cut the inside of the cylinder. As a result, the error in a 75-inch diameter cylinder (1 inch = 2.54 cm) was less than the thickness of a coin, which was quite advanced at the time.

　　The boring machine made an important contribution to Watt's steam engine

　　Without the steam engine, the wave of the first industrial revolution would not have been possible. The development and application of the steam engine itself, besides the necessary social opportunities, also depended on some technical prerequisites. Manufacturing steam engine components was far from as easy as a carpenter planing wood. Producing metal parts of special shapes with high precision required corresponding technical equipment.

　　In 1764, Glasgow University received a Newcomen steam engine requiring repair, and the task was assigned to Watt. After repairing it, Watt noticed how inefficient it was, like an old man gasping for breath, running shakily, and felt that it should be improved. He noticed that the main problem was that the cylinder repeatedly heated and cooled with the steam, wasting a lot of heat. Could it be kept constantly warm while the piston continued to work? So he spent his own money to rent a cellar, collected several scrapped steam engines, and was determined to build a new machine.

　　From then on, Watt tinkered with these machines day and night. Two years later, he finally produced a new machine. However, upon testing, the cylinder leaked everywhere. Watt tried every means, wrapping it with felt and oilcloth, but the problem persisted for months. Watt did not give up, and after unremitting efforts, he finally designed a condenser separate from the cylinder, which increased thermal efficiency by three times and reduced coal consumption to one-fourth. With this key breakthrough, Watt suddenly felt optimistic about the future. He consulted Professor Black at the university on some theoretical issues, and the professor introduced him to Wilkinson, the inventor of the boring machine. They used the method of boring cannon barrels to manufacture cylinders and pistons, solving the most troublesome leakage problem.

　　In 1784, Watt's steam engine was equipped with a crankshaft and flywheel, and the piston could be continuously driven by steam entering from both sides, eliminating the need for manual adjustment of the valves. The world's first true steam engine was born.

　　In 1880, horizontal boring machines with front and rear columns and worktables began to be produced in Germany. To adapt to the processing of extra-large and heavy workpieces, floor-type boring machines were developed in the 1930s. With the increase in milling work, floor-type boring and milling machines appeared in the 1950s. Due to the development of the watch and instrument manufacturing industry, equipment capable of processing holes with small distance errors was needed, and coordinate boring machines appeared in Switzerland. Now, to improve the positioning accuracy of boring machines, optical reading heads or digital display devices are widely used. Some boring machines also use digital control systems to achieve coordinate positioning and automated processing.

　　CNC boring machine

　　This article is excerpted from the book "The Story of Mechanical Inventions" published by Chemical Industry Press.