Underbody Coating
Underbody coating is a process of application of anti rust treatment chemical to the underside of a car body.
It covers the engine , floor board, door sill bottom, suspension lower arms, sub frame, exhaust pipe etc.
The process is done during the BIW stage of a car body and even on a fully built rolling chassis.
Purpose of the coating is to increase the service lif of the sheet metal by preventing the occurance of corrosion.
Types of underbody sealants.
1.Rubberized coating
2.Wax coating
3.Asphalt coating
4.Polyurethane coating
1.Rubberized undercoating.
It is easy to apply and offers sound-cushioning as well as protection from dust, moisture, and dings or dents.
In addition to your undercarriage, rubberized undercoating is also safe to use on wheel wells and quarter panels, and dries to a soft rubbery finish that prevents further rust, damage, or moisture seeps.
The coating can be painted over and, can be easily removed with an undercoating removal spray.
It is generally the best option for protecting your vehicle's undercarriage, as it provides the simplest and best protective measures against rust and moisture.
2. Wax coating.
A paraffin-based undercoating will be the cheapest and quickest option available with which to protect the undercarriage of your vehicle.
It will wear off quicker than other types of undercoating and will need to be stripped and reapplied at least once every year.
Wax-based undercoatings never truly harden. During application, they drip or flow into seams and cracks to provide protective properties.
They are usually available in a spray gun canister or in an aerosol can and offer at least a base protection in moderately humid climates.
3. Asphalt coating.
For standard vehicles, any of the aforementioned types of undercoating will provide sufficient protection.
For large trucks and heavy machinery, asphalt-based undercoating provides a bit of extra durability against rocks, chips, and moisture.
Asphalt-based undercoating generally contains a little bit of rubberized material that sets up firmly and also helps soften noise.
This type of undercoating also needs more cure time than the other three, and is NOT paintable, making it best to use only for undercarriages.
4. Polyurethane coating.
This type of vehicle undercoating is a little bit quicker and easier to apply.
Oftentimes, polyurethane undercoating will come in containers ready to preload into an application gun.
This type of sealant works by seeping into all cracks and seams, displacing salt and moisture and oozing around rusty areas to bond with and protect unoxidized metal.
It also sands quickly in case you'll need to perform bodywork and can be painted over.
This type of car undercoating generally requires a little bit more surface prep work before applying, sanding and applying an etching primer to bare metals before using are generally recommended.