Underbody Coating

Under body coating

Its a coating done on car under body to protect it from corrosion. Just like how people require shelter and additional care, cars need them too. Just parking your car inside a garage will not solve the problem as the car is exposed to ever-changing weather conditions especially in a country like India. Cars need to be given additional care especially during monsoon seasons. A car’s underbody is exposed the most to muddy terrains, potholes, debris and stones, and wet and even flooded roads that lead to corrosion of the underbody. Since the underbody is hard for us to inspect by ourselves, it is important to have an underbody coating in order to ensure your car is protected during these times.

The underbody coating that is most commonly used on cars in India and supplied by companies such as 3M is a thick, rubberized paint that forms a 2-3 mm thick coating all along the underside of the car when sprayed on. You also get a thinner clear coat underbody coating which is like a lacquer that coats the entire underside of the car. Some even inject rust-preventive coating material into crevices such as the bottom of doors and door sills, to protect them from rust. Some car manufacturers already offer some underbody coating straight out of the factory which is usually sprayed inside the wheel arches and under the floor board of the car.

Here are some benefits of underbody coating.

1. Rust Prevention

2. Sound insulation

3. Impact resistance

4. Cold and heat insulation

5. Hides welds, repairs & bodywork with spray

Types

Rubberized Underbody Coating

Rubberized Undercoating produces a textured finish which resists chipping, abrasion, exterior rusting and weathering. Provides one-coat build-up with no dripping, running or sagging. It helps protect the undercarriage of cars, trucks, vans and recreational vehicles from both corrosion and abrasion. The coating may also be used to protect wheel wells, quarter panels, interior side of fenders, door skins, under side of the hood and trunk lid, floor pans, and more. The rubberized undercoating also helps deaden noise, allowing for a more pleasant and quieter ride. The spray goes on as a textured black finish that resists chipping, abrasion, exterior rusting, and weathering. It provides one-coat build-up with no dripping, running, or sagging. Protecting your vehicle with an application of rubberized undercoating is advised for long-term protection of the undercarriage. Rubberized undercoating creates a protective barrier that seals out grit, grime and moisture that could otherwise corrode the metal components. This extra protection is a low-cost measure that can pay off by potentially extending the service life of a vehicle.

Wax Based Underbody Coating

Wax Underbody Coating Spray is a solvent containing, bitumen free anticorrosive agent based on wax, polymers and anticorrosive additives. The product can be precision and exhibits excellent sag resistance. It is fast drying, and even in a thin layer thickness it forms a closed water protecting film. The dry film shows good adhesion and anticorrosive properties. Wax Underbody Coating Spray is primarily used on wax coated vehicle underbodies and particularly for the secondary treatment of all protective coatings, like those based on PVC, PVC/wax, bitumen/rubber and rubber/resins.

Asphalt Based Automotive Undercoating

Asphalt Based Undercoating does provide some benefits over Waxed Based Undercoating. They both stick well to most any surfaces and do a great job sealing out moisture, road chemicals and oxygen. But mainly, Asphalt undercoating has the benefit of being less expensive. They protect anywhere up to 5 years and dry to a Firm to Hard coating.

Asphalt Based Undercoating does require a thicker film thickness meaning you will have to apply more product to the surface to be protected then if you use a Wax Based Undercoating. Additionally, Asphalt based products require more surface preparation because they can actually seal in rust and moisture allowing it to continue to grow. Finally, Asphalt based products continue to dry out over time causing cracks in the coating surface.

Coating process

1. The car is hoisted on a lift and the underbody is inspected for flaws
2. The under body is cleaned removing out the dirt and grease
3. Critical components like silencer are covered in a film to avoid the coating from sticking to it
4. Rest of the under body is spray painted evenly.
5. The silencer film is removed and zinc coating is sprayed on it
6. Final inspection is done to look out for flaws

Advantages

Fights rust

It plays an important role in keeping corrosion at bay. Underbody coating can come in handy especially near the sea, where there is too much humidity, and rusting is just one of those everyday things. Also it should be considered seriously a place where it snows in winter.

Absorbs noise

Very thick undercoating can soften the noises that reach the cabin. Since the undercoating is often made up of rubber it absorbs some of the rackets. The occupants of the car could spare themselves of the road noises, at least up to a certain extend.

Reinforcement

If the car comes with stock underbody coating, using another coating on top of it, is not going to hurt. It will offer additional reinforcement, protecting the underbody from water, road debris, gravel and small pebbles. There would also be a lesser chance for the factory coat to flake away.

Car life

Good undercoating not only defends the underbody from corrosion but also protects the engine and transmission as well! Less rusting coupled with slower wear and tear can surely add years to the lifespan of your vehicle. There would be fewer dents, dings and scratches on the undercarriage for you to fret about.

Disadvantage

A used vehicle may already have residue on the bottom of the car or even have spots of rust and corrosion. Undercoating will not help if corrosion already exists and the corrosion needs to be removed first before it can be applied, which can be expensive for the user.