Watch Those Thumbs!

Long, brown metal nail.
An original 7"in. long Roman nail found in Scotland.

Photo courtesy of glasgowsteelnail.com.

Nails may seem like a relatively modern and key material for frame construction; however, they have been in existence for thousands of years. Bronze nails found in Egypt have been dated to 3400 BC.[1] In Great Britain, early evidence of large scale nail making comes from Roman times 2000 years ago. Any sizeable Roman fortress would have its ‘fabrica’ or workshop where the blacksmiths would fashion the metal items needed by the army. They left behind 7 tons of nails at the fortress of Inchtuthil in Perthshire.[2]

Early wrought iron nails were made by heating iron ore with carbon to form a dense mass of metal which was fashioned into square rods and left to cool. A blacksmith would then reheat the rods in a forge, cut off a length and hammer all sides reshaping the rod into slimmer and slimmer profiles, with one end sharpened to a point. The pointed rod was reheated and cut off. The remaining smaller piece would be inserted into a hole in a “nail header” or anvil and with four blows of the hammer, a shallow pyramid shape known as a rosehead would be shaped on the side opposite the point, the nail “head.”[3] The most common head shape was the rosehead; however, broad “butterfly” (with two roughly equal triangular flanges), or narrow L-heads (with a single flange, producing an overall shape of an elongated “L”) also were crafted. L-head nails were popular for finish work, trim boards, and flooring.[4]
Around 1600 the first machine for making nails appeared in the United States’ colonies. The “Oliver” was a spring tilt-hammer operated by the foot of the worker. One end of the hammer was fitted to a wooden treadle by a crank. After the hammer had delivered its blow it was bought back to the vertical by a spring pole fixed to the beams of the nail shop. The weight of the hammer varied from just a few pounds to 30 pounds. When thick iron was being cut, as many as three people would operate the Oliver by jumping in turn upon the treadle. The work was very hard, for it has to be remembered that besides working the Oliver the hand hammer was being used and the bellows [for the forge] had to be blown. [5]

Three types of nails have been produced throughout history: hand-wrought (as described above), cut, and wire nails.

Thomas D. Visser’s description of cut and wire nails:

“Between the 1790s and the early 1800s, various machines were invented in the United States for making nails from bars of iron. The earliest machines sheared nails off the iron bar like a guillotine. The taper of the shank was produced by wiggling the bar from side to side with every stroke. These are known as type “A” cut nails. At first, the heads were typically made by hand as before, but soon separate mechanical nail heading machines were developed that pounded a head on the end of each nail. This type of nail was made until the 1820s.

“By the 1810s, however, a more effective design for a nail making machine was developed; it flipped the iron bar over after each stroke. With the cutter set at an angle, every nail was sheared off to a taper. With the resulting nails thus all oriented in the same direction, it became possible for the same machine to automatically grip each nail and form a head in a continuous mechanical operation. Nails made by this method are known as type B nails.

“Cutting the nails leaves a small burr along the edge as the metal is sheared. By carefully examining the edges for evidence of these burrs, it is possible to distinguish between the earlier type A nails and the later type B nails. Type A nails have burrs on the diagonally opposite edges, while the type B nails have both burrs on the same side because the metal was flipped for each stroke.

“This kind of evidence can be used to establish the approximate period of construction or alteration of a building. Type B cut nails continued to be the most common through most of the greater part of the nineteenth century.

“With the rapid development of the Bessemer process for producing inexpensive soft steel during the 1880s, however, the popularity of using iron for nail making quickly waned. By 1886, 10 percent of the nails produced in the United States were made of soft steel wire. Within six years, more steel-wire nails were being produced than iron-cut nails. By 1913, 90 percent were wire nails. Cut nails are still made today, however, with the type B method. These are commonly used for fastening hardwood flooring and for various other specialty uses.” [6]

Nail Sizes - Most countries, except the United States, use a metric system for describing nail sizes. A designation 50 x 3.0 indicates a nail 50 mm long (not including the head) and 3 mm in diameter. Lengths are rounded to the nearest millimeter.

In the United States, the length of a nail is designated by its “penny” size, written with a number and the abbreviation “d” for penny; for example, 10d for a ten-penny nail. A larger number indicates a longer nail. Nails under 1¼ inch, often called brads, are sold mostly in small packages with only a length designation or with length and wire gauge designations; for example, 1” 18 ga or 3/4” 16 ga.

Penny sizes originally referred to the price for a hundred nails in England in the 15th century: the larger the nail, the higher the cost per hundred. The system remained in use in England into the 20th century, but is obsolete there today. The letter “d” is an abbreviation for denarius, a Roman coin similar to a penny; this was the abbreviation for a penny in Great Britain before decimalization.[7]
Originally published in "Exceptional Places" Vol. 7, 2012, a newsletter of the Division of Cultural Resources, Midwest Region. Written by Mark Chavez.

[1]. Fourshee, Paul. “A Two-Bit History of Nails.” http://www.fourshee.com/history_of_nails.htm. Accessed 14, June 2012.
[2]. “The History of Nail Making.” http://www.glasgowsteelnail.com/nailmaking.htm. Accessed 14, June 2012.
[3]. Ibid.
[4]. Visser, Thomas D., “Nails: A Clue to a Building’s History,” http://www.uvm.edu/histpres/203/nails.html. Accessed 14, June 2012.
[5]. “The Black County Nail Trade,” http://sedgleymanor.com/trades/nailmakers2.html. Accessed 10, July 2012.
[6]. Visser, Thomas D., “Nails: A Clue to a Building’s History,” http://www.uvm.edu/histpres/203/nails.html.
[7]. “Nail (fastener),” http://en.wikipedia.org/wiki/Nail_(fastener). Accessed 14, June 2012.

Last updated: June 21, 2018