What is the difference between casters & wheels

Casters vs. Wheels: What’s the Difference?

It’s incredibly important for schools and facilities to run smoothly. Replacement casters and wheels play a critical role in everyday functions. When maintenance needs to move tools and parts during repairs, or when teachers or office staff need furniture and other equipment to move freely between classrooms or offices, mobility is mandatory.

Casters and wheels can be used to replace and refurbish existing mobile furniture and equipment, or they can be added to stationary items to make them mobile. This is why it’s important to know the difference between casters and wheels, to keep your school, or facility, rolling (pun intended).

What is a wheel?

To understand the difference between a wheel and a caster, these should be defined. Let’s start with the wheel. Wheels spin on an axle, and typically used for mechanical applications and are more heavy-duty than casters.

Types of products you’ll see wheels used on are utility carts, large capacity movers, hand trucks or dollies, wheelbarrows, lawnmowers, wagons, etc. Specific features taken into consideration during the purchase are the wheel’s size, bearing, material, and load capacity.

Wheels are made up of two types: solid or spoke. Solid wheels are constructed of one material, which could be steel, hard rubber, phenolic, polyurethane, or nylon. Spoked wheels consist of a tire molded onto another material, a core material, and are also called mold-on wheels. The core could be made up of aluminum, iron, steel, nylon, or polyolefin. The tire material that is molded onto the core typically consists of rubber or polyurethane.

What is a caster?

Now let’s discuss casters. One component of a caster is a wheel which is then installed in a frame, the second component. The frame is often called a bracket, rig or fork. These terms can be used interchangeably to refer to the frame which houses, or holds, the wheel. Casters can then be divided into two groups: swivel casters and rigid, or fixed, casters.

Swivel casters are designed with a wheel that can rotate 360 degrees within the caster frame. Casters that do not have a swivel bearing are considered rigid or fixed, casters. Items equipped with rigid casters can only move forward and backward. Rigid casters will feature brake options and can handle higher weight capacities.

A typical piece of equipment supported by casters has either four swivel casters or a combination of two swivel casters and two rigid casters. This caster configuration is especially useful when you have to move equipment when there is limited space to maneuver.

For instance, if you have a four-swivel caster cart, it will maneuver perfectly in a small, tight area. However, controlling this cart for moving in straight lines or long distances will prove difficult. If your cart is configured with two swivel and two rigid casters, this will make rolling long distances and straight lines much easier while still working well within tighter spaces.

What types of casters are available?

There are several caster types based on how the caster will be attached to your furniture or equipment. Two common caster types are stem casters and plate casters.

Stem casters – made up of an assembly with a wheel (or several wheels) mounted onto a fork, with a stem for attaching it to the bottom of an object; used for providing mobility to an otherwise stationary item and are typically made of polyurethane, or soft rubber caster wheels, which will not scratch or mark-up floors.
Plate casters – made up of a wheel or compound wheel with a plate on top for simple mounting. This type of caster can handle heavier loads; use for turning an otherwise stationary object into a vehicle, primarily for material handling applications.

How to buy wheels and casters

There are four basic questions to ask yourself when making a purchase decision on casters and wheels.

What weight capacity is needed per caster?
What size of wheel is needed?
What attachment style is required?
What kind of surface is the equipment or furniture rolling on?

You can determine what weight capacity you need, per caster, by taking the total weight capacity and dividing it by the number of casters minus one. To calculate the total weight capacity, add together the weight of the piece of furniture or equipment and the weight of the load. So, for example, let’s say you have a total weight capacity of 1500lbs. for a cart that has four casters. Your equation will look like this: 1500lbs./4 casters – 1 which is 1500/3 = 500lbs. needed per caster.

For wheel size, keep in mind that the larger the wheel, the easier to roll, and therefore the smaller wheel will be more difficult to roll. It’s also important to remember that the larger the wheel, the taller your furniture or equipment will be.

When deciding on attachment style, determine if you have lots of surface space to attach the caster or do you have limited space. If there’s space, you can use a plate top attachment style, but if there is limited space, use a grip or friction ring caster or threaded-stem casters.

Finally, what type of surface are you rolling your furniture or equipment on? If you are on carpet or a chair mat, you may want to choose plastic or metal casters. If your surface is smooth but sensitive like tile or hardwood, then you may want polyurethane caster.

With so many types of wheels and casters, as well as options for each, it can be challenging to find the right fit. However, by following the four guidelines above, this will help you get exactly what you need. Whether you're replacing existing casters or wheels or converting a piece of furniture or equipment, it's possible to make an informed buying decision following these guidelines.

We hope you found this guide helpful. If you have further questions or need assistance with purchasing casters or wheels, feel free to contact us or start a chat with one of our knowledgable sales staff. To learn more about solutions to common school maintenance concerns, please visit the School Fix^® Blog.

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