Underbody Coating
INTRODUCTION:
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
In Indian road conditions, a cars underbody is most prone to corrosion. Underbody coating provides long term protection from corrosion to car’s underbody. It also protects parts like internal body panels, frame rails and other inner cavities that are not physically accessible but are prone to corrosion.
Benefits
• Minimizes Sound: It minimizes the sound from underneath the car resulting a noiseless, smooth driving experience.
• Heat Insulation: It insulates the interior of the car from extreme temperatures from beneath the vehicle providing a comfortable cabin experience.
• Anti-chipping property: If any stone hits the coating it does not get chipped away hence protects the underbody from exposure to water.
TYPES OF UNDERBODY COATING:
1. RUBBERIZED UNDERCOATING:
Rubberized undercoating is easy to apply, and offers the best protective coating for car’s undercarriage. It cushions surfaces against moisture, rust, dings, and dents. Rubberized undercoating is safe to use on wheel wells, quarter panels and dries with a soft rubbery finish.
2. ASPHALT-BASED UNDERCOATING:
It has higher level of protection suitable for lorry's, Trucks or heavy machinery vehicles. It’s made up with some bits of rubberized material to aid in noise reduction. It offers extra protection against chips and moisture but is not paintable.
3. POLYURETHANE UNDERCOATING:
this type of underbody coating requires some surface preparation work before application, like degreasing, and applying an etching primer to the bare metal.It is easy to apply and works by sealing up cracks. The compound displaces salt and moisture and protects the unoxidized metal from rust. It’s often sold in canisters that are ready to preload into an application gun.
4. WAX OR PARAFFIN-BASED UNDERCOATING:
Wax or paraffin-based undercoating sprays are the cheapest and quickest options available. However, their results don’t last long, and you may have to apply a fresh coat after only a few months. In addition, the wax isn’t very adhesive on a metal surface. Its main advantage is that it seeps quickly into cracks and seams, and offers moderate protective properties against moisture.

The above picture shows the completed process of underbody coating.

PROS:
Rust prevention
Sound insulation
Easy maintenance
Teflon coating
Minor Scratch Protection
CONS:
High Cost
Not Long Lasting
Risk of damage during application