Door Knobs

Door knobs have been used around the world for centuries, and were first manufactured in the United States in the mid-nineteenth century.

Though spherical or ball-shaped door knobs are considered the hardest to turn, this shape is still the most common. Egg-shaped door knobs are the easiest for most people to use. Doorknobs have been made of many materials, including wood, ceramic, glass, plastic and different types of metal. Brass is one of the most popular materials because of its excellent resistance to rust.

The average doorknob is 2.25 in (5.715 cm) in diameter. The basic components are the knob rose, shank, spindle, and knob-top. The knob-top is the upper and larger part that is grasped by the hand. The shank is the projecting stem of a knob and contains a hole or socket to receive the spindle.

The knob rose is a round plate or washer that forms a knob socket and is adapted for attachment to the surface of a door. The knob is attached to the spindle, a metal shaft that turns the latch of the lock.

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American doorknob designs and materials have changed throughout the years. In colonial times the first door hardware was made out of wood, and involved simple latches and strings.

Round knobs first appeared around the time of Independence. Decorative hardware, including knobs, emerged after the Centennial Exposition of 1876. Before this time, most door hardware was imported; 95% in 1838.

Glass knobs were rare until a faster and cheaper manufacturing method was developed based on pressing. Pressed glass knobs were popular from 1826-1850, followed by cut glass through 1910.

Wooden knobs were introduced in the late 1800s and were phased out after 1910. China or ceramic knobs were mainly imported from France and England until the mid-1800s, when the first U.S. patent was granted for making knobs out of potters clay.

Before 1846, metal knobs were made from two pieces brazed together or three pieces soldered together. Cast metal knobs were introduced around 1846. In the late 1800s, composite metal knobs were introduced as a less expensive knob.

The main body was made out of iron or steel, covered entirely or in part with a veneer of bronze or brass. During the last half of the nineteenth century, many patents were issued regarding the spindle methods of attaching metal knobs for lock use, as well as designs for ornamenting these knobs.

In 1870, a compression casting method was introduced that accelerated ornamentation of hardware.

Many of the Victorian doorknobs were made of cast bronze with ornamental patterns. During this period, a dozen major companies and many smaller firms produced hundreds of patterns of ornamented hardware, in addition to cast and wrought metal, glass, wood and pottery knobs. From 1830-1873, there were over 100 U.S. patents granted for knobs. Collectors have catalogued over 1,000 antique doorknob designs into 15 types based on shape, material, and design pattern. The best grade of knobs during this period were usually made from cast bronze or brass.

Around 1900, cast metal and glass knobs were introduced that incorporated ball bearings in the shanks of doorknobs. In operation, the knob shank rotated on sets of ball bearings fitted in the hardened steel cones. This reduced friction, assured closer adjustment, and eliminated endplay of the knobs. Other materials popular during the early 1900s included bronze and porcelain.

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