What Is a Tube Chassis?


What Is a Tube Chassis?

Every car out there is more than the shiny body you see. Beneath all of that is a structure that supports the body and the other parts that make up the car. The structure is a chassis and there are many types, including the tube chassis.

A tube chassis is a type of framework that uses a network of pipes to give structure to a car. You can make it bespoke, and you need only metal tubes. Although race cars today are a fusion of different types of chassis, the tube chassis is still the predominant type used.

In this article, I will talk about the two types of chassis. I have also discussed what a tube chassis is and what it is made from. To conclude, I will consider whether a tube chassis is lighter.

What Are the Two Types of Chassis?

What Is a Tube Chassis?

The main types of chassis that dominate the car manufacturing industry are:

  1. The body-on-frame chassis

Other names for this chassis include conventional chassis and frame-full chassis. It is usually made from square tubes welded together, into a solid framework. A ladder frame attaches the chassis to the body of the care.

With a simple design, it is easy to manufacture and its strength ensures it comes out of accidents with minor damage. It has a high load-bearing capacity and in case of any damage; it is easy to repair.

Drawbacks of this chassis include high fuel consumption, lower car refinement, and a lot of vibrations when driving. Currently, only big commercial cars have this type of chassis. Examples are SUVs and trucks.

  1. The unibody chassis or unconventional chassis

Other names for the unibody chassis are integral or monocoque chassis. It comprises metal sheets stamped and connected with the body of the car. Unlike the conventional frame, there is no separate frame to connect the body and the chassis. 

The chassis gets its strength from the welding, gluing, and bolting of the metal parts. This chassis is light, and it uses a lesser amount of fuel. It also has better handling and refinement, and it is seen in many passenger cars. Sedans, hatchbacks, minivans, and saloon cars all use a unibody chassis.

Disadvantages of this type of chassis include the complexity of its design and its vulnerability to accidents. Although it has lesser vibrations and gives a smoother ride, a little brush with a car like this can squeeze it in a way that repairs are impossible.

Both the conventional and monocoque chassis are made from materials like carbon fiber, carbon steel, and aluminum. The chassis is an unseen structure that is often neglected until things begin to fall apart.

To save yourself the stress of paying $1000 to prices above $10,000, you should conduct checks every six months to identify any problems that may arise from the normal use of your car.

What Is a Tube Chassis?

A tube chassis or a tube space frame is a three-dimensional framework that was a step up from the ladder chassis. Circular tubes or square-cut tubes are placed in different directions and welded to form a singular structure. By placing the tubes in different directions, this chassis can withstand all kinds of forces.

It has a very high mechanical strength and you will find them in racing cars. To provide more strength, sturdy structures are used below the doors. This modification raises the height of the doors and makes the cabin difficult to access. Another disadvantage of this chassis is its impracticality.

Despite how strong the tube chassis is, it cannot feature in regular cars. Factories cannot reproduce them because of how complex their designs are. You can build it 100% from scratch once you have a plan to follow.

The tube chassis is rigid, and this makes for a smoother ride. It also gives the best ratio of weight and rigidity. This means that the car can be strong without being heavy. The first road car made with this frame was the Mercedes 300SL Gullwing. 

What Are Tube Chassis Made From?

What Is a Tube Chassis?

Like the name says, tube chassis is made from metal tubes. Aluminum can be used to shave off some weight, but you must pay attention to the strength and fatigue life before choosing it.

Most tube space frames are made from steel structural tubes. 

Steel tubes of grades 1018 and 1020 are mild steel tubes and they have just enough toughness and strength for amateur builders to work with. These builders are usually aiming for a chassis that will last for a long time. These grades are unaffected by the high welding heat and there is no need to treat them after welding.

A steel tube in grade 4130 chromoly is stronger than the other two grades and to restore its mechanical properties, you need to treat it after welding.

Is Tube Chassis Lighter?

Because of the density of the pipes, the tube chassis is lighter than other chassis with a similar weight. The lightness of the chassis does not diminish its strength. The three-dimensional makes it strong, even stronger than the ladder chassis.

This complex network of tubes provides a kind of safety in race cars that other types of chassis cannot give. Even though the tube chassis is light, the cars are actually heavy.

Why Is Tube Chassis Not Used in Regular Cars?

The first reason is their incompatibility with mass production. They are extremely complex and costly to build. A lot of time is also required to make a single tube chassis. The tubular structures take up a lot of space, leaving little to no room for a roomy cabin.

There is no way a family of 4 can fit into a racing car. Even the luxury cars that use this chassis often have room or only 2 people. The cars with tube chassis are also heavy and are totally impractical for daily use.

Examples of cars that use a tube chassis are Lamborghini Diable, all Ferraris before the 360M, Jaguar XJ220, etc.

Gui Hadlich

Hey there! I'm Gui. To be honest, I'm not really that interested in cars. But what I'm really, really not interest in is spending lots of money fixing my car up. Thankfully, I have a father-in-law who's obsessed with cars and a brother getting a PhD in internal combustion engines, so I get to learn about fixing cars. And with Fixing Engines, I hope to help you save a lot of money and take good care of your cars.

Recent Posts