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Caster and Equipment Wheel Bearings
 

Caster Wheel Bearing Options

Roller Bearings: The default standard bearing for caster wheels, sometimes known as needle bearings. Offering high load capacity, long life and easy rolling. Low speeds with short travel and minimal side thrust. Designated with "R" in Service Caster part numbers, SCC-30R3420-PHR.

Sealed Pedestal Precision Ball Bearing : A great maintenance free option (no grease required) and upgrade compared to roller bearings. Ball bearings provide a more quiet, easier rolling operation. The spanner bushing is integrated into the bearing design. Designated with a "B" in Service Caster part number, SCC-30R3420-PHB.

Delrin Bearings: Delrin a type of plastic known for its strength and resistance to water absorption. These bearings also offer a chemical resistance to most fuels and solvents. Designated with a "D" in Service Caster part number, SCC-30R3420-PHD.

Precision Bearings: A pair of Precision bearings replaces the roller bearings and spanner bushing. Higher speeds and duration plus a more quiet ride is possible over plain sleeve and roller bearings. Not recommended for high side thrust. Designated with a "P" in Service Caster part number, SCC-30R3420-PHP.

Tapered Bearings: Select when extended use, higher speeds up to 10 mph, and increased thrust from turns is expected. Tapered bearings provide optimum performance for extreme capacity applications; used in our Series 92 casters as an example, designated with a "TPB" in Service Caster part number, SCC-KP92R1030-PHT.

Choosing Pneumatic Wheels for Casters
 

Choosing Pneumatic Wheels for Casters

Pneumatic wheels have two major benefits over many other caster wheels. In addition, they come in a variety of sizes, styles, and tread patterns. Read on to find out if a pneumatic wheeled caster would be useful for your application!

The first major benefit of pneumatic caster wheels is that they offer a very cushioned ride. This is useful for applications that need protection from excess vibration, or travel over rough surfaces such as rocks, concrete, dirt, or grass. Marching bands use casters with pneumatic wheels often for heavy instruments.

The second major benefit is that pneumatic wheeled casters provide an extremely quiet ride even on uneven and rough surfaces. This is helpful in any environment where noise is an issue.

A variety of options are available for pneumatic wheels. Choose selections for tube and tubeless depending on application. Multiple bearing types as well as bearing sizes allow for pneumatic wheels to be used on many caster frames. Tread styles also vary greatly, and include smooth, ribbed, diamond, sawtooth, and knobby tread patterns.

Custom Casters and Wheels at Service Caster Corporation
 

We Are Your Source for Custom Casters

Welding a Custom Caster

There are thousands of different casters and caster wheels on the market, enough for any situation, environment, and job. Every now and then there is a project that requires a little extra work to meet unique or specific requirements and thats where Service Caster’s custom fabrication team comes in.

Whether you are a do-it-yourselfer or a major manufacturing facility, custom work can be tailored to fit your needs.


Getting the Custom Caster You Need

Custom Tread Lock
How do you take advantage of our abilities to custom make your perfect wheel? The first step is to give us a call and discuss with us the project that you’re working on. We will ask questions like, “What kind of surface will the wheels roll on?” and “Will there be high speeds, or side thrust on the caster?” These questions will help us determine if you actually need custom work, or if there is something out there in the “caster-verse” that is readily available. Once we’ve determined you need custom work, we will develop with you the exact specification of your wheel and caster. Everything from the top plate or stem down to the very bottom of the wheel’s tread.

In addition to phone calls, specs and images can be emailed to us, and physical samples can go a long way to making sure you get exactly what you need.

How to Choose a Replacement Chair Caster
 

Choosing New Replacement Casters for Chairs

You’re not stuck with the original casters that come with your office chair, and a broken caster isn't the end of your chair. There are many options for replacing the casters, and below you'll find the information you need to make an informed decision.

The first thing you will need to know is the stem size of your current casters. To find this out, you will have to remove the stem from the chair. From there, check out of our How to Measure Caster Stems page for more information. This is a very important step as casters may have one of several styles of stem, and use either imperial or metric standards.

After that, determine the primary location of use. Will it be on a low pile carpet? Plastic or glass chair mat? Hardwood or tile floor? This information is critical for determining the right wheel material. On carpet, nylon (plastic) or metal wheels are acceptable. On hard surfaces, especially damageable surfaces like hardwood, you want to get a soft wheel like neoprene, thermoplastic elastomer (synthetic rubber), or urethane. Soft rubber is also an option, but it may leave unsightly black marks on flooring where other soft treads will not.

From this point on, the choices are primarily aesthetic. Hooded or unhooded? If hooded, perhaps a color other than black, such as the Windsor Antique or bright brass? These choices won’t affect the functionality, but may be far more pleasing to the eye than the original casters.

Take a look at our online selection of casters or give us a call at 1-800-215-8220 to speak with a salesperson about all available options.

How to Measure Caster Stems
 

How to Measure Caster Stems

To Measure Caster Stems, Determine Your Stem Style

There are 3 main styles of caster stems; these are Grip Ring, Grip Neck, and Threaded. Choose from the images below to select the stem type that matches your caster's stem style and either click the image or scroll down to the corresponding section.

Grip Ring Stem
Grip Neck Stem
Threaded Stem

Watch the Video for Measuring Caster Stems

Measuring a Grip Ring Stem

Grip ring stems are one of the most common connection types for office chairs. For the most accurate results a micrometer or caliper should be used to measure the diameter of the stem, but below we will demonstrate some ways to get the measurements using common household items. We recommend using at least 2 of the methods described below to ensure accuracy.

Measuring with a Wrench

To measure a Grip Ring stem with a wrench, simply gather both a 7/16" and 3/8" wrench. Place the open end of the wrench around the stem, as shown below.

Measuring Grip Ring with a Wrench

Whichever wrench fits almost perfectly will be the size of your stem.

Note: A tiny bit of wiggle room or "play" is to be expected when using the wrench method. The 3/8" wrench will never fit on a 7/16" stem, and a 7/16" wrench will be very loose on a 3/8" stem.


Paper Wrap Method

For this method of measurement, simply take a small strip of paper and wrap it around the stem. Mark the paper with a pen or pencil where it overlaps, careful to keep the wrap tight. Then measure the strip from the start of the wrap to the mark.

If the ruler measures 1-3/16", you have a 3/8" diameter stem.

If the ruler measures 1-3/8", you have 7/16" diameter stem.

how to measure grip neck stem

taking stem measurement

Measuring a Grip Neck Stem

Grip neck stems are most commonly used in wooden or metal tube furniture in conjunction with a socket. In most cases, if you measure the length of the stem and it is 1.5" long, you have a 5/16" diameter stem. If you are confident that is not what your stem measures, please measure it (or have it measured) precisely with a caliper or micrometer for length and diameter so we can find a match.

Correct Measuring Locations:

measuring grip neck stem

Measuring a Threaded Stem

Threaded stems require very specific measuring tools in order to find the correct diameter and thread pitch. Because of the many sizes and variations (metric, standard) the only way to be 100% confident of the measurement is to use a thread gauge. Pictured below is a thread gauge and threaded stem. If you don't have your own thread gauge, most hardware stores will be able to help you.

thread measuring tools

how to use thread measuring tools

Send Us Your Caster

Would you like help measuring or replacing your casters? Send us one of your casters (stem included) and we'll make sure you get the proper replacement. Click here to send us caster samples.

Also See: how to measure caster wheels.

How to Measure Caster Wheels
 

How to Measure Caster Wheels

There are 4 critical measurements when it comes to replacing a wheel. These are the wheel diameter, wheel width, hub length, and bore diameter. Other dimensions will be discussed as well, but are primarily shown for clarification.

The wheel diameter is the distance measured across the side of the wheel. Occasionally the wheel will have its diameter and width stamped or molded into the wheel itself, so take minute to check and see if that is the case. If not, simply measure across the wheel. Bear in mind that wear can cause up to ½” of material loss, so if your current wheels are particularly worn you may need to round up to the nearest half inch. Because there are very standardized wheel sizes, this measurement can typically be taken with just a tape measure.

The bore diameter is the internal size of the bore. This measurement is required in order for the wheel to fit the existing axle assembly properly. While looking at the side of the wheel, measure across the inside of the opening in the center of the wheel where the axle passes through. This tends to be a more precise measurement than the wheel diameter. If you have a micrometer or caliper, that would be the preferred method of measuring. Another method would be to insert drill bits until you found one that matched the size of the bore.

Wheel width is the widest part of the tread material. This measurement is not nearly as critical as the hub length, but is very helpful for locating the same or similar wheels. Generally a tape measure will suffice for this measurement.

The last primary measurement is the hub length. This is the distance between each side of the wheel through the bore. Proper hub length allows the wheel to fit between the caster fork assembly with minimal play. This measurement is more important than wheel width, because it determines if the wheel will fit the frame or not. The wheel width does not determine if the wheel will fit in the fork. A tape measure will not typically fit through the bore to take this measurement. Instead, use a piece of dowel or pencil and insert it through the bore. Hold one end of the dowel flush with one side of the bore, and mark the other side. Then you can remove the dowel and measure from the flush end to the mark.

You will notice Hub Diameter and Tread Width on the images above. These are shown for reference and to reduce confusion. Note that the tread width is actually smaller in many cases than the wheel width.

With these measurements, you will be able find a replacement wheel. Remember, if you have any issues or need further assistance, we’re here to help. Give us a call at 1-800-215-8220.
International Caster and Wheel Sales
 

Service Caster International Caster and Wheel Sales

Service Caster Corporation distributes casters and wheels around the globe. We are your international caster source. Choose from a huge selection of casters, featuring our own brand, plus over 200 name brands guaranteeing that we can fulfill your caster needs.

Call 1-800-215-8220 to place a caster order, or for more information on international shipping, setting up an account, and any further assistance you require.

Spanish speaking representatives available; Representantes de habla hispana disponible.

Is Stainless Steel Non-Magnetic
 

Is Stainless Steel Non-Magnetic

Over the years, we’ve had a few people contact us in regards to our stainless steel casters. “Hey!” They say, “You’ve sent me the wrong casters. These are supposed to be stainless steel, but they’re magnetic.” We understand the concern, but have no fear… magnetism and stainless steel are not mutually exclusive. For example, stainless steel kitchen knives are often magnetic.

There are various types of stainless steel with a range of magnetic properties based on the atomic structure of the steel. Without getting too complicated, chromium content is what gives the steel its stainless properties. Sometimes, other materials are added to give specific attributes to the steel such as malleability or hardness. One such added material is nickel, which when combined with the steel creates the non-magnetism.

Our most commonly sold stainless steel casters are made with ferritic stainless steel, and they are magnetic. Some applications, such as MRI machines or special lab equipment, must have non-magnetic steel. If this is the case for your application, please give us a call at 1-800-215-8220 to discuss more options.

What Are Kingpinless Casters?
 

What Are Kingpinless Casters?

Kingpinless casters, as the name suggests, are casters that lack a kingpin. Is this a good thing or a bad thing? What is the purpose of the kingpin, and why would you remove it? Read on to find out.

The kingpin is a feature found in most light to heavy duty swivel casters, though it is generally not used in ultra-light duty casters such as chair casters. It is essentially a rivet, and its job is to hold the top plate and the fork of the caster together, allowing for a ball bearing housing between the two units that in turn allows the caster to swivel properly. The kingpin also tends to be a weak point in situations that put heavy stress on the caster, such as shock loading. In these cases, the kingpin can bend or even break, allowing the ball bearings to fall out and causing caster failure.

The answer to this caster failure is the kingpinless caster. Kingpinless casters are precisely engineered and machined to allow swiveling without a kingpin. The lack of the kingpin removes the casters’ typical weakest link, and provides a caster that can handle shock loading and heavy stress without failure.

Most kingpinless casters are only available at the heavy and extra heavy duty levels of casters, since the easier-to-produce kingpinned casters can handle light and medium duty jobs with ease.

What is "Durometer"
 

What is a Durometer

While looking at casters and caster wheels, you may have come across the terms “Durometer” or “Shore Durometer” and an associated number and letter. What do they mean? Where did they come from? Why are they there? Read on to find the answer to these life-changing questions.

Lets get the confusing part out of the way first. Durometer is both a measurement and a tool for measuring. In other words, you measure the durometer of an item with a durometer.

But what exactly is a durometer measuring? The hardness of an item. There are many durometer scales represented by a letter(in the caster and wheel industry we use Shore A and Shore D) ranging in numerical value from 0-100. The higher the number, the harder the item is on that particular scale. For instance, a rubber band has a durometer of 25 A. Skateboard wheels (or many of the polyurethane wheels we sell) might be between 85-95 A. This doesn’t mean that they are extremely hard, just that they are one of the hardest materials the Shore A scale can measure.

What happens when an item is harder than the Shore A Scale can measure? That’s when we move on to the Shore D scale. Any of our harder wheels, such as a phenolic resin wheel, will be measured on the D scale. A phenolic resin wheel has a durometer of 90 D. Another example of an item on the D scale would be a hard hat, which has a durometer of around 75 D.

Ultimately, the durometer of a wheel can help the user figure out how the wheel will react to its environment and the floor it is on. Will it be durable enough? Will the wheel damage the floor? Will the floor damage the wheel? Will the wheel roll over debris? These questions can be answered (or at least approximated) through the use of durometer measurements.

What is Semi-Steel
 

What is Semi-Steel

If you’re looking for an industrial or heavy duty caster, you’ve no doubt come across the term Semi Steel. And, unless you have a background in metallurgy, chances are you’re not sure what it is.

As it turns out, semi steel is actually a type of cast iron, with steel scrap thrown in the mixture for good measure. In fact, most semi-steel has quite a bit of steel scrap in it. The result is an alloy that is excellent for use as caster wheels, for a variety of reasons. Semi steel features easy castability, low cost, and machinability, just as cast iron does. It also has added strength, impact resistance, and ductility from the steel. This makes semi-steel a perfect balance of cost effective strength for many medium and heavy duty casters.