Nuts. Bolts. Screws. Pins. Nails. It’s all basically the same, right? Not quite. There are many different types of fasteners, each of which have particular uses and purposes. From the temporary solutions provided by clevis pins and cotter pins to the handiness of coupling nuts, there are many options for those in need of fasteners. Even within the “bolt” category, there are plenty of options from which to choose.
Bolts, first manufactured in 16th century France by a company called Besson, have threaded rods and are used to hold two pieces of material together. Unlike screws, they don’t have pointed ends and are held in place by nuts and washers. Round head bolts are arguably the most common.
Round Head Square Neck Bolts
Commonly called carriage bolts, these types of bolts were first used in the 19th century to secure pieces of old-fashioned carriages together and became popular for industrial use in 1869. They are typically made from zinc-plated or stainless steel and are used to fasten wood to wood or metal to wood. They have round heads and square necks, intended to keep them from rotating after installation. Carriage bolts are now very common, ranging in size from a half inch to a foot in length.
Round Head Ribbed Neck Bolts
Like carriage bolts, these are unable to turn after installation, as long as they’re tightened with nuts. The ribs positioned close to the head lock them in place, preventing them from rotating. Their lengths have a shorter range of only three-quarters of an inch to three inches.
Round Countersunk Head Bolts
Also called plow bolts, round countersunk head bolts are beveled under the head so that they can sit inside countersunk holes. They are well-suited to heavy equipment, since they are designed to resist turning when they are tightened with nuts. In length, they range from one to six inches.
Square-Head Steel Bolts
Essentially functioning as opposites of carriage bolts, these instead feature square heads and round necks. They are intended to offer more surface for a wrench to grip, hopefully leading to reduced slippage. Like carriage bolts, they range in length from three quarters of an inch to a foot.
Choosing the right bolt for your project is essential to its proper execution. Not all bolts are designed for every application. Do your homework, and pick the right one. You’ll be glad you did!