Service Caster Corporation Blog

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.

How To Measure A Caster Wheel

Occasionally, you may find yourself in a situation where you need a replacement caster wheel. The caster fork and frame is fine, or perhaps your application doesn’t use a caster fork, and you just need a new wheel to replace an existing wheel. As long as you can remove the existing wheel, you’re in luck.

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.

How to Choose a Replacement Chair Caster

Did you know you’re not stuck with the cheap plastic casters that come with every office chair ever made? There are many options for replacing the casters, and below we’re going to give a quick rundown on what information you’ll 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 several styles of stem as well as 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 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.

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.

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.

Call Service Caster at 1-800-215-8220 to find out if Pneumatic Wheel Casters are appropriate for your application.

Custom Casters and Wheels at Service Caster Corporation

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

Custom work can take the form of the very small, such as a caster stem for a chair that does not fall into the modern day standards, or the very large, such as a wheel for mining operations.

: Welding a Custom Caster

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.

: Custom Tread Lock

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

Finally, we’ll have our design team, machinists, and assemblers produce your custom caster!

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 casters 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.

Take a look at kingpinless casters at our online catalog.

Flat Free Foam Filled Tires

What are these flat free foam filled tires, and why use them? Let’s find out.

The flat free tire can be used in any situation a pneumatic tire could be used, such as garden cart wheels, wheelbarrel wheels, hand truck wheels, and caster wheels. The difference is that instead of being air filled, the tire is filled with a polyurethane foam matrix. The foam maintains the flexability, shock absorption, and easy movement of a pneumatic tire, but won’t deflate even if punctured.

Flat free tires are great for any application where there is a high likelihood of tire puncturing, such as a warehouse floor with metal shavings or staples, or for anyone who simply doesn’t want to have to worry about refilling a pneumatic tire. This feature does add to the cost of the tire.

Ask us at Service Caster about flat free foam filled tires today!

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’ve got 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 casters, 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.

Service Caster Videos

The caster pros at Service Caster are now producing videos, offering another format for users to gather information from the world of casters and wheels. These videos will offer all sorts of demonstrations and how-to’s from a real life perspective, and are made by actual Service Caster sales reps and employees. These videos are specifically made by us for you to deal with the most common issues that come up.

You can find the video collection at our Video page. At the moment these videos include “How to Replace a Grip Ring Stem,” “How to Measure a Caster Stem,” and “Choosing Hardwood Floor Safe Furniture Casters.”

We hope these videos are both helpful and informative!

What Is A Durometer?

Shore A Durometer with Polyurethane Wheel — A Shore A Durometer Next To A Polyurethane Wheel

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.