Why have we stopped using cage nuts in towbar production?

All parts that are fixed to your car need some sort of nuts and bolts to keep them in place. For many years, in towbar production and fitting, we have been using cage nuts to secure towbars to vehicles and this has proven to be both safe and effective. However, we have recently begun to use a new type of nut and bolt when fitting towbars which we think towbar fitters and vehicle users alike will love.

This development is in line with our shift from powder coat paint to E-coating. Since 2019, most of our towbars have been fitted with OEM captive nuts instead of cage nuts and we think it would be beneficial for you to learn why. In this guide we will cover:

  • What are cage nuts?
  • Why did we use cage nuts?
  • Why have we stopped using cage nuts?
  • What are we using instead of cage nuts?
  • How will this benefit towbar fitters and the end-user?

What are cage nuts?

75% of applications use a regular nut and bolt. Cage nuts provide a way for a nut to be held in place with a clip without the need to weld it together. A cage nut is a nut in a spring steel cage that surrounds the nut and the cage part of the nut holds the bolt in place. There are two wings on either side of the cage which can be pinched together, allowing you to insert the bolt and hold it in place once the rings have been released.

In relation to installing a towbar, the mounting point on the vehicle is not always accessible and sometimes the threads can become blocked if the paint is too thick. The threaded part on the nut is retained on the part of the towbar which fixes to the chassis but it can be difficult to fit your hand in to secure a traditional nut and bolt from the outside which is why a cage nut is often used.

Why did we use cage nuts?

Cage nuts provide a solution to a problem caused by powder coat paint because the paint sometimes collects in the threads, making it difficult to screw the designed fixing in place. Cage nuts solve this issue and have proven to be a brilliant engineering solution. They are extremely versatile, provide a secure fixing and allow for thick coatings of paint on the threads during powder coating.

We have used cage nuts for many years now because you can leave the hole blank. The cage nut provides a way to hold the nut in place without welding it because the cage nut sandwiches around the part. Usually, the fixing would be rigid and set in position once it had been welded but the cage nut provides a secure fixing without the need to weld.

Why have we stopped using cage nuts?

Cage nuts can sometimes be tricky to fit but they were necessary due to the issues surrounding thick layers of paint caused by powder coating. However, we have recently started using a new paint method called the E-coating system. E-coating applies a much thinner layer of paint and doesn't damage the threads in the nut, as well as being more consistent. This means it is now much easier to use traditional nuts when fitting a towbar because the threads are less prone to being compromised by thick paint.

We are currently progressing towards using this new system in the future and believe it will be better for both manufacturers and fitters in the long run.

What are we using instead of cage nuts?

Now we use the E-coating paint system, there is a much thinner coating of paint so it doesn't build up in the threads which means we can now use OEM grade captive nuts. The nut is now spot welded to the towbar by holding the nut onto the towbar and applying an electric charging current that sticks the nut to the towbar. This is different from using a traditional welding method as there is no need for a filler metal and no sparks flying which can damage the thread.

Transitioning towards using captive nuts provides us with much more flexibility without excess paint in the threads so it allows for a bit of misalignment of the threads which was not possible with powder coat paint and cage nuts.

How will this benefit towbar fitters and the end-user?

We are now using an OEM style captive nut that is spot welded to the part and negates any thread damage. It is also high tensile which avoids any thread stripping and makes it much easier to secure the bolt into place. The new captive nuts are OEM graded so you can be sure they are high standard, as used across the automotive industry. They also work extremely well with the E-coating paint system so will complement our new method of painting towbars moving forwards.

Overall, we have experienced great success from using cage nuts and will continue to use them as they are extremely secure, durable and versatile. As we transition towards using the E-coating paint system, the OEM graded captive nuts will perfectly complement the new paint system while meeting the wider automotive industry standards.