Back when I started this blog I posted some pics from the Watts Campbell factory in Newark NJ, a more or less early 20th Century steam engine factory that was stuck in amber for fifty years.
One of the goals I’ve had for this blog is to bring the obscure histories of fundamental technologies to life again. After the mess of the election and the economy I thought that I would explore the history of the machine tool industry and how it came to be in Britain and The US. Here’s a History Channel video.
What makes machine tools different from the jewelers, instrument and wood cutting lathes that had been around for centuries is that in a machine tool the cutting bit is held rigidly in a clamp rather than held by hand. This means that the work of the cutting bit need to have some way to move either the bit or the work. Which typically means an accurate screw, gear, or both.
The person that solved the screw problem by making a screw for a lathe that Maudslay cut more accurately than any screw that exeisted heretofore. He then used that screw to build a screwcutting lathe more accurate than any that had existed.
Maudslay also came up with way to produce very flat surfaces for tool and part guides. Which allowed the development of the planer and the shaper.
On the other side of the Atlantic another of the critical machine tools that would drive the industrial revolution was coming into being in the shop of Eli Whitney. That was the horizontal milling machine. The milling machine works in the opposite manner as lathe in that it the cutter that rotates, not the work. The oldest extant milling machine, seems to have come from Whitney’s shop, though when it was fabricated is unknown. Until fairly recently the mill could be seen at the Peabody Museum at Yale, but I’m not sure that it’s still there.
In any case the actual machines that were invented are not as important as the nteworks and clusters that evolved from the shops. Both Maudslay’s and Whitey’s shop spun off people who went to work for other shops evolving the tools as they went and teaching other men who would move on to take their techniques and skills to create still other shops.
Maudslay’s standard of accuracy carried him beyond the use of ordinary calipers, and he had a bench micrometer of great accuracy which he kept in his own workshop and always referred to as “The Lord Chancellor.” It was about 16 inches long and had two plane jaws and a horizontal screw. The scale was graduated to inches and tenths of an inch; and the index disk on the screw to one hundred equal parts. Speaking from the standpoint of fifty years ago, Nasmyth says: “Not only absolute measure could be obtained by this means, but also the amount of minute differences could be ascertained with a degree of exactness that went quite beyond all the requirements of engineering mechanism; such, for instance, as the thousandth part of an inch.”15
Maudslay’s record, as left behind him in steel and iron, would give him a secure place in engineering history, but his influence as a trainer of men is quite as great. He loved good work for its own sake and impressed that standard on all in his employ. Clement, Roberts, Whitworth, Nasmyth, Seaward, Muir and Lewis worked for him, and all showed throughout their lives, in a marked way, his influence upon them. Other workmen, whose names are not so prominent, spread into the various shops of England the methods and standards of Maudslay & Field (later Maudslay, Sons & Field) and made English tool builders the leaders of the world for fifty years.
J. G. Moon, who afterwards became manager of James Watt & Company of Soho, the successor of Boulton & Watt, was apprenticed to Maudslay, Sons & Field and gives the following picture of the shop at the zenith of its prosperity.
There were not more than perhaps a dozen lathes in use there, with cast-iron box beds such as we now know; but nearly all the lathes had been constructed by the firm itself and were made without a bed, the poppet or back center and the slide-rest being supported on a wrought-iron triangular bar, varying in size from, say, 3-in. to 6-in. side. This bar was supported on cast-iron standards, and reached from the fixed lathe head to the length required of the “bed.” If the lathes were self-acting, there were two such triangular bars with the guide screw running between them. The advantage of these lathes was great, for if a large chuck job was on hand, the bars could be withdrawn from the fixed head, supported on standards, and anything that would miss the roof or swing in a pit beneath could be tackled.
There was one screwing machine or lathe which all apprentices in the vice loft (as the fitting shop in which the writer was apprenticed was called) had to work during their curriculum— this was a small double-bar lathe with a guide screw between. The fixed head was on the right of the operator, and the lathe was worked by hand by means of a wheel very much like a miniature ship’s steering wheel. This wheel was about 2-ft. diameter, with handles round the rim, and we apprentices were [p.47] put at this machine to develop the muscles of the right arm. The advantages of having the fixed head on the right (instead of on the left, as in an ordinary lathe) was that in cutting a right-hand thread the tool receded away from the start and ran off the end, and thus prevented a “root in,” which might happen if, whilst pulling at the wheel, you became absorbed in the discussion of the abilities of a music-hall “star” or other equally interesting topics with a fellow-apprentice.
The same thing happened on the American side of the Atlantic centered in the Connecticut River Valley and in the burgeoning firearms and clock industries.
By the end of the 1850’s most of the machine tools that you can still see in shops today had been created and evolved by these clever people.
The new tools allowed more rapid production methods and much greater precision, which meant that parts could be made to be more or less interchangeable. As the abilities of the machine tools increased the products that could be made with those tools. By the turn of the last century the things that could be manufactured ranged from large generators.
to fine watches.
With everything in between.
Here’s some more resource about early machine tools.
It’s a good thing that there are some of those old shops still around.
When you look at that antique whatever, think about the tools and work that went into making it. In this day and age of CNC and plastics we have to a large degree forgotten just what goes into making something. Still in every shop I’ve ever worked at the old tools are still there and still get used. It’s still easier for somebody skilled on the old machines to run out a part than it is to create the program and have a computer make it. For that matter a part can be drawn out on a sheet of paper or even a dirt floor and still be a work of art.