Which Casters Are Best For Weld Tables

Why Are we Talking About Casters?

It’s kind of weird to be discussing something as boring as casters, especially when we build things that are WAY sexier. But as it turns out, our tables are only as bad ass as the weakest link – and when it comes to heavy duty tables, the weakest link is always the caster! I mean, you can make a massive leg that can hold 100,000 pounds! But if you put a caster on the end of it you’re limited to the amount of weight those bearings and other components can handle before coming apart. So, in our quest to build the best welding tables on the planet we’ve had up our caster game! So I’m going to explain what we’ve learned, and why we do it the way we do.

Caster Components

First thing’s first! Let’s define what all goes into a caster so we can make sure we have a common language to discuss. Borrowing from Caster Connection, here’s the basic breakdown of a caster with a top plate.

• Top Plate – The top of the caster is called the top plate. It’s usually rectangular, with four holes, one in each corner. The top plate serves as the mounting point for the caster. There are some casters which use a threaded stem instead of a top plate, and while those are very convenient they are MUCH weaker than the plate mounting method. I mean to start with, you have 4 bolts instead of one. Let’s just start there…
• Wheel – The wheel is obviously the whole point of a caster. However, not all wheels are created equal, and you need to choose the right wheel for the job. Some wheels are made of plastic, some from steel. Some have phenolic tread, some have inflatable rubber tubes, some have a steel surface. Each is best suited for a different purpose.
• Fork– This is the part that the wheel bolts to. Just like the forks on a front bicycle tire. And the construction of the forks can play a role in the capacity of the caster.
• Bearings – Of course, you could just stick a pin in the center of a wheel and it will spin. But you’ll have a lot of friction unless you put a bearing in between them to remove friction. There are a lot of different types of bearings, and arguably this may be the most important differentiator for casters in general.

Ok, Let’s Talk About Bearings

Since I just made the claim that the bearings are probably the most important part, let’s take a look at why. First of all, there are several different types of bearings, but rather than going through all of them, I’m going to stick to the main types of bearings used in casters.

Ball Bearings

All of the casters we evaluated for our tables have at least one bearing – the Wheel bearing. However, different vendors, at different price points, include different bearings. The main bearings most of us are familiar with are just plain ball bearings.

Ball bearings have little round balls sandwiched between a couple of metal rings that allow them to spin with very little friction. These are great for many applications! Here’s what Wikipedia has to say about these types of bearings:

As one of the bearing races rotates it causes the balls to rotate as well. Because the balls are rolling they have a much lower coefficient of friction than if two flat surfaces were sliding against each other.

Ball bearings tend to have lower load capacity for their size than other kinds of rolling-element bearings due to the smaller contact area between the balls and races.

https://en.wikipedia.org/wiki/Ball_bearing

These are probably the most common types of bearings, but the main concern is the load capacity. When we build welding tables we want them to be able to handle really heavy projects! So we outright reject any caster for our heavy duty tables that relies on ball bearings.

Needle roller Bearings

The other alternative is the needle bearing. These bearings substitute the balls for cylinders which typically have rollers that are at least four times longer than their diameter. The larger surface area of the needle roller bearing allows them to support extremely high radial loads.

Now there is no such thing as a free lunch, so if you’re going to get much higher load capacity you have to give something up. And in this case the speed of rotation is the tradeoff. Ball bearings can spin much faster! But since we’re just rolling tables around speed is the least of our worries! The other disadvantage of a roller bearing is cost. You may be able to purchase several ball bearings for $1, as opposed to several dollars for one roller bearing.

If I can get on my high horse for a minute – I HATE companies that purport to build something really world class, but then cut corners on the tiniest things in order to increase profits!!! So we might spend an extra $20-40 or so on casters for our weld tables, but who really cares when the table itself costs 100 times more! Texas Metal Works is NEVER going to make that kind of tradeoff. It’s just stupid.

The Bearings WE Have Chosen

The cheap casters that most companies are pushing, just to reach a price point, typically use two ball bearings on the outside edges of the wheel, with a bolt going through them. Sometimes these casters seem great when you spin them in your hand! They really roll smoothly and spin fast! That might lead you to believe they are superior! But they aren’t.

This is an actual disassembled view of the core of our casters.

There is an outer sleeve, with a needle roller bearing inside that is the full width of the sleeve, followed by an internal sleeve, and held together with a heavy duty hollow bolt that has a grease zerk right on the end so you can pump fresh grease into it periodically to keep it rolling smooth.

This is complete overkill if you don’t have a heavy duty application! But we’re not going to offer a wussy caster for some people and a heavy duty one for others. It’s the best we can get, or we’re not doing it.

The OTHER Bearing

There is one other type of bearing used on these casters, but it’s only for the swivel casters. It’s called a thrust bearing. This is the one at the top which allows the caster to rotate. Kind of like a Lazy Susan you might have on a table for spinning food around to everyone. These basically have a couple of plates with balls in-between them, like the ball bearings previously mentioned, but horizontally situated.

All of the casters we evaluated use this type of bearing for the swivel functionality, so it’s just a matter of ensuring it has the load rating required to match the rest of the caster design.

Brakes

Casters can have one of many different types of braking mechanism (or none at all). The most common types are:

• Side Brake/Thumb Lock Brake: A lever or paddle on the side of the wheel locks the wheel in place by pressing against the tread. This is a simple and cheap brake mechanism, but they can be tricky to operate and are less reliable.

• Total Lock Brake: This type of brake locks both the wheel and the swivel mechanism, preventing both rolling and rotating. It is ideal for situations where maximum stability is needed. Sometimes these casters have just one pedal which needs to be pushed down, or pulled up to unlock. These work, but are sometimes hard to operate.

• Directional Lock Brake: This brake only locks the swivel, allowing the wheel to roll but preventing it from rotating. It’s useful when you need to guide a cart or equipment in a straight line.

• Tread Lock Brake: A mechanism that presses directly onto the tread of the wheel to hold it in place. These brakes are common for light- to medium-duty applications, but in my opinion they are the worst of the options.

Our Locking Mechanism

For our casters we chose a more costly, but MUCH more convenient mechanism. Our casters have two pedals on them. Step on the ON pedal to lock both the wheel rotation and swivel – step on the OFF pedal to unlock. Simple, strong and convenient!

Wheel Types

Ok, so the bearings aren’t the only thing bearing weight. The physical wheel must also hold everything you put on it. But wheels are often comprised of two parts:

• Tread: This is the outer layer or covering material wrapped around the wheel core, similar to a tire on a car. It can be made of materials like polyurethane, rubber, or other elastomers, providing traction, shock absorption, and floor protection.
• Wheel Core: This refers to the main structural part of the wheel, usually made of a rigid material like cast iron, aluminum, or nylon. The wheel core provides the strength and support needed to carry the load.

Wheels are also built from different materials:

• Polyurethane: Durable, offers good floor protection, and is resistant to chemicals and abrasion. Ideal for applications requiring quiet operation and for use on a variety of surfaces, including carpet and hard floors.
• Rubber: Provides a smooth and quiet ride, suitable for delicate floors or areas that require noise reduction. However, rubber wheels can wear down faster and may leave marks on certain surfaces.
• Nylon/Plastic: Lightweight and resistant to chemicals, moisture, and wear. Commonly used in environments where easy rolling on smooth surfaces is needed. They can be harsh on delicate flooring.
• Steel: Extremely strong and can handle heavy loads. Used for industrial applications but can damage floors and are noisy. They are ideal for rough and uneven surfaces.
• Cast Iron: Very strong and durable, often used for heavy industrial loads. These wheels are resistant to heat but can be quite loud and cause floor damage.
• Phenolic Resin: Made from layers of resin-impregnated fabric compressed under heat. They are strong, can handle high temperatures, and are resistant to oil and chemicals, but they may not be suitable for rough surfaces.
• Aluminum: Lightweight yet strong, often used in combination with other materials like rubber or polyurethane to provide a durable and smooth-rolling surface.

Our Heavy Duty Casters

In our case, our wheels are a hybrid, with a cast iron core, and a polyurethane layer wrapped around it. This give the caster excellent weight bearing capability, but also rolls smoothly and can handle slightly rough floors.

As a purely aesthetic choice you’ll notice that our casters have a black iron core, and black poly tread… just to be awesome! You simply aren’t going to find these casters anywhere else because we have them made specifically for us!

Additionally, if you look close you can spot some of the grease zerks which allow you to periodically put fresh grease in them to keep them rolling super smooth.

So hopefully this wasn’t too boring! It’s interesting how much you can learn about what appears to be a simple product when you’re forced to tear it down to the absolute basics in order to maximize performance. And that’s exactly what we’ve done. We choose the best of breed for every component of the caster, and they have performed flawlessly in thousands of applications deployed all over the world!

A Preview of What’s to Come

Although we think we offer the best casters on the market already, you can’t just sit on your laurels and wait for someone to outdo you! So we are preparing to offer an even more impressive set of casters!

Our new casters will be FULLY SUSPENDED! And this is born from the fact that our own shop floor is 50 years old and has lots of bumps in it. When we roll tables across it they tend to bounce around, which is just unpleasant. So the answer is suspended casters.

Just imagine casters that absorb all the bumps, offer total lock brakes, and have a weight bearing capacity exceeding 1,000 lbs!

The bad news is that these could potentially add hundreds of dollars to a build, but that’s a problem we’re working on solving to make it much more economical to have the Ferrari of casters on your projects!