The nail isn't the most glamorous accessory in a handyman's (or woman's) tool belt, but it's arguably the most important. While duct tape can perform many magical tasks, it doesn't hold a candle to the trusty nail. The simple metallic spears are literally the glue that holds our world together and keeps the roofs over our heads.
For all its understated excellence, the nail comes in a surprisingly wide variety of styles. Joist hanger, spiral shank, egg case and apple-box represent only a minor sampling of specialized nails. There's less diversity when it comes to the size of nails since they can only measure between 1 and 6 inches (2.5 to 16 centimeters) in length. Anything shorter is classified as a brad, and longer ones constitute spikes.
A 1-inch (2.5-centimeter) nail, the smallest kind, is referred to as a 2 penny nail, denoted as 2d. The higher the penny designation, the longer the nail. Likewise, the longest nail in the bucket is a 60 penny, or 60d nail. The penny system has been around since the 15th century in England, but its exact origin is unclear [source: Thomas]. As the label implies, it probably had something to do with price per unit of weight. The "d" abbreviation was borrowed from ancient Roman currency; it refers to the denarius coin, which was the Roman equivalent of the penny.
Like pennies, some nails are made of copper -- as well as aluminum, nickel, brass and other metals. The ones we hammer most often, however, are steel nails. Steel is a metal alloy of iron and carbon. Made from a process involving iron ore purification and intense heat, the resulting steel has superior strength, which explains why it's used so often in construction projects.
On the flip side, steel also has a potential weakness that it inherits from iron.
The Advantages of Hot-dipped Nails
Left untreated and in contact with certain chemicals, steel can rust. Rust, or ferrous oxide, occurs when iron elements oxidize. When rust overtakes a steel nail, it causes corrosion and can leave unsightly stains on wood materials. For that reason, the steel nails you buy at the hardware store probably aren't naked, or untreated.
Most nails have undergone one of three types of coating processes:
- Galvanizing: steel nails coated with zinc particles to resist rust formation
- Bluing: nails heated to form an oxidized surface layer for added strength
- Cementing: nails covered in resin to increase the friction between them and the building material
[source: Forest Products Laboratory]
When it comes to rust resistance, galvanized nails are the most effective. These work well for outdoor applications that could subject nails to moisture and rain, as well as corrosive chemicals in treated wood. Zinc arms nails against rust because it's more reactive than iron and therefore oxidizes more easily. That way, the zinc forms zinc oxide and protects the metal below.
The galvanization process takes place via electroplating or hot-dipping. In electroplating, nails are doused in an electrically conductive solution and zinc. The reaction of the steel with the solution binds the zinc to the nail to form a thin layer [source: Bliss]. The primary disadvantage associated with electroplating is inconsistency; the zinc particles may not cover the nail uniformly, degrading its overall quality.
Many carpenters opt for hot-dipped nails over electroplated ones when dealing with wood materials. Hot-dipping involves submerging the nails in molten zinc, thus covering them more evenly. Some hot-dipped nails receive two zinc washings, in which case they're referred to as double-dipped. Essentially, the thicker and smoother the amount of zinc coating, the better the nail will avoid rusting.
In addition to warding off oxidation, hot-dipped nails also have improved staying power. The coarse zinc particles cling more tightly to whatever they're being hammered into. Consequently, they perform well for attaching parts of house trim, decks, stairs and window frames [source: Locke and Locke].
Moreover, hot-dipped and electroplated nails hit on only a fraction of those on the market. So before you pull out the hammer or nail gun, first consider the appropriate nail for the job.
Related HowStuffWorks Articles
- Bliss, Steven. "Troubleshooting Guide to Residential Construction." Craftsman Book Company. 1997. (April 3, 2009)http://books.google.com/books?id=iwSasc7rowcC
- Bolt, Steven. "Roofing the Right Way." McGraw-Hill Professional. 1996. (April 3, 2009)http://books.google.com/books?id=iDjyitMjGHkC
- Forest Products Laboratory. "The Encyclopedia of Wood." U.S. Department of Agriculture. Skyhorse Publising, Inc. 2007. (April 3, 2009)http://books.google.com/books?id=mUGSaiTsBAIC
- Locke, Jim and Locke, James. "The Well-Built House." Houghton Mifflin Harcourt. 1992. (April 3, 2009)http://books.google.com/books?id=AB6bvI031LAC
- Thomas, Steve. "Penny Nails." This Old House. (April 3, 2009)http://www.thisoldhouse.com/toh/asktoh/question/0,,216638,00.html