The task chair has been around for centuries before the corporate workspaces we’re familiar with today existed, so it’s no wonder that many people don’t know much about its most instrumental part – the caster. Here’s everything you didn’t know and need to know about chair casters.
A Brief History
Casters are a much less modern invention than most may expect. Charles Darwin is thought to be the first person to use casters when he added wheels to his traditional armchair to make it easier to move around his study in the 17th century. However, chair casters weren’t patented until nearly two hundred years later in 1876 by African American inventor David A. Fisher, who recognized the need for workers to be more mobile and comfortable in the workplace at the height of the Industrial Revolution.
Design Tidbits
The National Institutes of Health recommend a five-point base for task chairs with casters for maximum stability and decreased chances of chair tipping. Today’s casters are typically made of a variety of materials including glass, leather, plastic, iron, aluminum, stainless steel, rubber and nylon.
Need-to-Know Facts
The different materials used to make caster wheels each serve a unique purpose based on their firmness. Hard wheel casters are best suited for carpeted floor, whereas softwheel casters are made for wood, tile, linoleum and chair mats.
The way a caster is built to rotate is also important. There are four different types of casters:
- Rigid Casters: Rigid casters are the most basic type of caster. They aren’t built to rotate and are designed to move objects in a straight line. An everyday example of a rigid caster are the back wheels on a shopping cart.
- Swivel Casters: Swivel casters allow an object to rotate a full 360°. A common example of swivel casters can be found on the front of a shopping cart.
- Industrial Casters: Industrial casters are designed to transfer up to 30,000 pounds and are designed to incorporate rigid or swivel casters. Dolly carts, for example, use industrial rigid casters.
- Braking and Locking Casters: Any type of caster can include a special brake feature which is low in cost and stops the wheel from turning. It’s usually a small lever that can be pulled to stop an object’s movement. Braking mechanisms found on some models of step stools can lock or retract automatically for safety whenever a user sits or stands on them.
Rigid casters are the most common type of caster, while most task chairs use swivel casters.
Safety Tips
If you need to replace a caster, be sure to replace all casters and not just one. To replace a broken caster, be sure to remove the caster and measure the length and diameter of the stem, or the mount that connects the caster to the object it’s attached to. This is especially important so the balance and alignment of the casters is not negatively affected, which can increase chances of chair tipping.
Using hard casters on a hard floor is dangerous and should be avoided. It can lead to accidents or injury, and will destroy both the floor and the casters over time.
