Underbody Coating

UNDER-BODY COATING FOR AN AUTOMOBILE

( Submitted by - Jithin B Nair )

Uunderbody coating is a dense coating applied to the undercarriage of an automobiles. Its normally spray painted, which can be done manually or be automated, on the car after it’s assembly.

Most cars come with a factory undercoat, but some lower end cars are only provided partial underbody coating. In such cases the coating can be applied as soon as it is out of the dealership or after the car’s underbody surface is cleaned and prepared before painting.

The reason being the different standards followed in different countries which specifies the minimum area needed to be painted with undercoat by the manufacturer of the vehicle. The European Standards are the best due to the reason that it is mandatory for the cars there to have a complete underbody coating right out of the dealership/manufacturer.

• The damages could caused due to rust, wear and tear, damages from chemicals and salt, etc.
• All surfaces must be pre-cleaned and prepared with appropriate surface treatments before any process is carried out to prevent spread of any above mentioned causes and to prevent the same in the future.

* In new cars, undercoating can be done as a precaution to prevent any damage prone due to wear and tear on the surface of the body, which could arise from loose surfaces, rocks, etc. on roads.

* In old cars, it can prevent further damage than which has already happened to the underbody.

A standard undercoating dries by 30 minutes and completely cures by 24 hours. And a professional grade undercoating only takes 10 minutes to dry and but 72 hours to fully cure.

Types
1) Rubberized Underbody Coating

This is the most popular type, and generally though to be the best type of underbody coating for a car. But if the body/surface isn’t prepared properly prior to applying these type of coating, it could trap moisture and cause the rust to spread without being noticeable outside the coating. It’s also one of the easiest method to do. It also helps in sound (road/Tyre noise) insulation for the car.

• Wax Based Underbody Coating

This is a short term solution as it will wear away in a few months of time. But is protects the best against moisture and spread of rust. Its the most affordable out of all processes.

• Asphalt Based Automotive Undercoating

It’s normally used and best suited for heavy vehicles, because it provides a thicker than usual amount of coating, thus more protection than other methods. But the downside is that it provides little to no sound insulation for the vehicle. Its more time consuming and harder to apply this type of coating.

• Polyurethane Underbody Coating

Its best used to cover and close up the splits, cracks and fractures on the surface of the vehicle’s underbody. It bonds with the metal surface and is good against corrosion. Unlike the other methods, you can paint over an already existing polyurethane coating.

Advantages-

• Protection and further prevention against rust and corrosion caused by time or environmental factors.
• Prevents the underbody paint from the factory from chipping.
• Reduces road noise and improves sound insulation, thus helps in drive comfort.
• It also protects the engine and transmission from weathering out which prolongs the vehicle’s life.

Disadvantages-

• The undercoats will wear off with time and gradual damage, so it must be reapplied every 3-5 years.
• It works best on new cars.
• It increases the weight of the vehicle.
• If rust and corrosion is already present then it’s required to treat the corrosion and rebuild the lost surface before applying an undercoat.