When Not to Use a Threaded Stem on Your Caster

When Not to Use a Threaded Stem on Your CasterWhen you are picking out a caster for your unique application, there can be a lot of things to consider and not knowing what affects your decision can cause you to choose the wrong caster for the job. This is why finding the right service professional to work with will help make sure you find the right caster to perform the task that needs to be completed.

One of these decisions which offers many options is the way your caster is fixed to your cart. You can purchase a caster that has a plate that bolts to the bottom of your cart, a caster that is press fit into a hole, or with a threaded rod that will turn into an insert in your cart or be inserted into a through hole and attached by a nut. All of these have right and wrong uses, so let’s look into the details of each option.

Does the Caster Replacement Need a Particular Mounting?

This may seem like a strange point to make, but if you are replacing a caster on a cart or trolley it is much easier to use a new caster with the same mounting configuration. It is not impossible to change this, such as using a threaded rod caster with a nut that was originally used for a plate mounted caster, but you need to consider why the original design used that particular type of caster.

Does the cart see stresses that require the caster to be held by four bolts rather than one threaded rod? It is easier to continue to use a press fit rod rather than transferring to a threaded insert. Do you need this added security for the caster? Here is a caster that is only available with top plate mounting:

  • EHD Series, Extra Heavy Duty Casters: Hamilton Casters and Trucks have designed these casters for heavy industrial applications where it is necessary to ensure dependable operation such as in industries like shipbuilding, jet engine factories and by heavy equipment manufacturers. For this reason, Hamilton only makes these casters available with top plate mounting. The casters are machined from drop forged steel for a rugged and easy swivel operation. The casters include HPI premium raceways that are CNC-machined & hardened. Load capacity ranges from 840 lbs. to 10,000 lbs. with wheel diameters of 6” to 12”.

Do You Have Access To Your Method of Attachment?

This is another consideration that seems easy, but can be tricky. If you are going to drill a hole to mount a threaded insert for the caster with a threaded rod, can you access the area to drill the hole? Is your mounting surface so thin that the threaded rod would protrude out from the top? If you are looking to use a through hole and apply a nut do you have access to adequately torque the nut after installation?

Threaded casters work well on tubing and pipe applications, but make sure you have the access you need to properly attach the caster well. By not tightening the caster you risk the caster becoming un-threaded which can lead to damage or breaking the threaded rod. For this reason it is important to always use a lock nut or lock washer when mounting a caster.

  • Rhombus 357h Heavy Apparatus and Equipment Caster: Designed to work with ease, this solid and robust caster is designed for applications like cooking equipment, food dispensers and other appliances. This caster is available with many different mounting configurations including top plate, threaded stem and press fit stem. With a sheet steel construction that is zinc plated this caster looks great and has excellent performance provided by a double ball race swivel bearing. The caster also includes a directional brake as an option, and has capacities up to 130 Kg.

Is the Threaded Rod the Right Length to be Safe?

While having a threaded rod that’s too long can cause problems if the stem bottoms out in the hole, it can also be problematic if the threaded stem is not long enough for the application. The first issue would cause the caster to stick out from the bottom of the threaded mount so that when the weight is applied to the caster, it is placed on the threaded stem rather than on the top plate of the caster, leading to stem breakage.

With the second issue, any sideways pressure would be applied to the length of the threaded stem, so a short stem could mean that the pressure is applied only on the bottom half of the threaded insert and may lead to insert failure. Here is a caster with various lengths of threaded stems available:

  • Colson 2 Series: This is a basic caster design that works well for a variety of applications. This Colson caster comes in capacities of up to 325 pounds and can include optional top locks or total lock systems. Threaded Stem Mount options come in thicknesses of ½”, 5/8”, and ¾” with lengths of ¾”, 1”, 1 1/2” and 1 ¾”. The wheel options are Performa Rubber, Polyolefin, Thermo, cast iron, and Polyurethane HI-TECH.

Contact Douglas Equipment to Learn More

If you are picking out a caster and need a guide for the options available, there is no place better to turn than Douglas Equipment. We have been in the business of quality casters and material handling equipment for almost 60 years and in this time our dedicated service team has learned what it takes to find the right caster for the task at hand. We are confident that we can help you find the right caster to perform the job you need completed at an affordable price.

From our location in Miami, we can easily service the entire United States and quickly ship products to South America and the Caribbean as well. There is no worry about your delivery being delayed. If you are local to South Florida, you can call us at 305-888-3700, and national customers can call us toll free at 800-451-0030. For those who prefer to contact us online one of our service professionals will get back to you as soon as possible to help you find the caster that best fits your needs. We look forward to hearing from you soon.