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Casters are available in different styles, two of the most common being threaded stem and expanding adapter. Both styles consist of a wheel assembly, and they are both designed for use on the bottom of objects. You can install on them on the bottom of chairs, toolboxes, medical equipment, industrial machines and more. Once installed, you can then roll the object.
What Are Threaded Stem Casters?
Threaded stem casters are characterized by the use of a threaded stem. Located on top, the threaded stem consists of a built-in bolt with external threading. All threaded stem casters feature a bolt-like stem with external threading.
You can install threaded stem casters in threaded holes of the appropriate size. The stems’ external threading will “catch” the internal threading of the holes.
What Are Expanding Adapter Casters?
Expanding adapter casters are characterized by the use of a tube-like grommet that expands during installation. Also known as expanding stem casters, they feature a protruding cylindrical stem. The stem, which is also located on top of the casters, is designed to expand.
You can install expanding adapter casters in unthreaded holes. After placing the stem in a hole, you can expand them. Most expanding adapter casters feature a special nut that, when turned, will expand them.
Differences Between Threaded Stem and Expanding Adapter Casters
They may look similar, but threaded stem and expanding adapter casters aren’t the same. Only threaded stem casters feature threading. They have a stem with external threading, which allows them to fit in threaded holes.
Expanding adapter casters feature a stem as well, but the stem isn’t threaded. Instead, they feature a smooth stem that’s designed to expand.
Expanding adapter casters are easy to install. You don’t have to worry about matching the thread size; only threaded stem casters feature threading. Just place the casters’ stems in the holes, followed by turning the casters’ adjustment nuts to expand them.
You can quickly remove expanding adapter casters after installing them. Turning the adjustment nut in the opposite direction will contract the stem. With the stem now smaller, you can pull it out of the hole in which it’s installed.
Threaded stem casters, on the other hand, may provide greater stability than their expanding adapter counterparts. As their external threading catches the internal threading of the holes in which they are installed, they will lock into place. The end result is a more stable, smoother rolling operation.