What’s the Difference Between Stem and Hollow Kingpin Casters?

Kingpin casters are available in different styles, such as stem and hollow. They both feature a swivel action, meaning you can turn them in all directions. The swivel assembly is known as a kingpin. It’s found above the wheel where it supports a 360-degree range of rotation. While both stem and hollow kingpin casters have a kingpin, however, they aren’t the same.

What Are Stem Kingpin Casters?

Stem kingpin casters are characterized by the use of a rod-like stem. The stem is typically threaded. You can install kingpin casters by twisting this stem into a threaded hole on the bottom of the object with which you want to use them.

There are other types of stem casters available. Casters with a kingpin-based swivel assembly and a rod-like stem are known as stem kingpin casters. Casters with only a rod-like stem and no kingpin-based swivel assembly, in comparison, are simply known as stem casters.

What Are Hollow Kingpin Casters?

Hollow kingpin casters feature a kingpin-based swivel assembly as well, but they don’t use a stem. Instead, hollow kingpin casters have a hole at the top. When inspecting the top of a hollow kingpin caster, you’ll see this hole. It’s found at the top of the fork.

You can install hollow kingpin casters by sliding a bolt through this hole and into the bottom of the object. Hollow kingpin casters essentially have a hollow center at the top. This hollow center supports a bolt for installation. Sliding the bolt upwards from the bottom of the caster will allow you to install it.

Differences Between Stem Kingpin and Hollow Kingpin Casters

There are a few key differences between stem kingpin and hollow kingpin casters. You can distinguish between these two common types of kingpin casters by looking for a stem. Stem kingpin casters, of course, have a stem at the top, whereas hollow kingpin casters do not. Hollow kingpin casters are also referred to as stemless kingpin casters for this reason.

Hollow kingpin casters are typically smaller than stem kingpin casters. They have a lower-profile design, which makes them a popular choice for chairs and other types of furniture.

Both stem kingpin and kingpin casters have a swivel action, which is achieved with their kingpin-based swivel assembly. Stem kingpin casters simply have a built-in stem at the top, whereas hollow kingpin casters have a hole. You can still install the latter using a bolt, but you’ll have to slide the bolt upwards through the bottom of the hole and into the object.