
The method for automotive chassis sealing is: 1. Thoroughly clean and dry the asphalt, oil stains, and other contaminants from the car chassis; 2. Cover the engine oil pan, transmission housing, exhaust pipe, and other parts with masking paper to avoid spraying; 3. After wrapping the key areas, use a high-pressure spray gun to apply the chassis anti-rust coating evenly over the vehicle chassis, with a thickness between 1mm to 3mm; 4. Wait for 2 to 4 hours after spraying. Chassis sealing involves spraying a highly adhesive flexible rubber resin onto the chassis to isolate it from the external environment, achieving functions such as anti-corrosion, rust prevention, and sound insulation, thereby extending the vehicle's lifespan.

A while ago, I DIYed the undercoating for my beloved car. It’s actually not difficult but requires careful steps. First, thoroughly wash the car and lift it onto a jack stand. Use a metal brush and specialized rust remover to clean rust and grease from every corner of the undercarriage. After drying, carefully wrap high-temperature components like the exhaust pipe and drive shaft with masking tape, then tightly cover the tires and rims with plastic sheets. Choose a rubber-based undercoating spray, shake the can for three minutes before opening, and maintain the spray gun about 20 cm away from the undercarriage while moving evenly during application. Apply the first thin layer evenly and wait ten minutes for it to dry to the touch, then apply a second thicker layer. Key areas like the fuel tank and inner wheel arches need three to four layers for sufficient protection. Finally, wait half a day for it to fully dry before reinstalling the underbody panels. The most critical part of the whole process is ventilation and protection—wearing a mask and goggles prevents harm from chemical fumes.

Listen buddy, I've learned my lesson the hard way with undercoating. Last time I cheaped out on inferior materials and it started peeling in three months. Now I know better - only resin-based double-layer formula armor coating is reliable. You must remove the tires and underbody panels before application; many people skip this for convenience but the results are much worse. The cleaning process is the most time-consuming - I specifically bought a pneumatic descaling gun to blast away even the mud on shock absorber springs. Spraying must be done in a dust-free booth as outdoor airborne particles can ruin the coating. Keep spray cans at constant temperature; in winter they need pre-warming in a heated room. Don't rush to reassemble after spraying - best to let it cure in the garage for two days. Final warning: never spray on brake discs or radiators - I made that mistake last year and nearly had an accident.

As a seasoned mechanic with over a decade of experience in repair shops, there are three crucial steps for underbody coating. Cleaning must be thorough—after lifting the vehicle, first scrub the chassis with neutral detergent, especially using a brass wire brush to remove rust from weld seams, then dry it with a blower. Covering must be precise—high-temperature components like exhaust pipes and drive shafts should be wrapped with triple-thickness aluminum foil tape, while suspension ball joints need masking tape. Spraying should be layered—use a professional underbody coating spray gun at a 30 cm distance for crosshatch application. The first layer is a thin coat of rust-proof primer, followed by a rubber protective layer after half an hour of drying, and finally a wear-resistant topcoat. Ensure each layer is surface-dry before the next; in summer, using a fan aids optimal drying. After completion, avoid water exposure for three days.

I've seen all kinds of underbody coating failures at the modding club - the key is choosing the right material. Beginners should use polyurethane spray cans for their easy application and low odor. Here's the process: Remove all four tires and underbody plastic guards, pressure wash the area, then dry thoroughly with a heat gun. Pay special attention to masking oxygen sensors and electrical connectors. Apply the coating working outward from the center of the underbody in three stages. Start with a light mist coat, wait ten minutes for a heavier second application, then focus on high-impact areas like wheel wells. Use infrared lamps to speed drying between coats. Most people forget to remove masking for final touch-ups on edges. Properly dispose of empty cans to avoid environmental contamination.


