Discovering rust on your car can be disheartening. Rust, if ignored, can spread aggressively, turning your vehicle into a shadow of its former self and significantly reducing its lifespan. While modern cars come with factory rust protection, daily use and minor damages can compromise this defense, paving the way for corrosion. The thought of a costly body shop repair might cross your mind, and indeed, professional rust repair can be expensive.
However, don’t be discouraged. If you are willing to tackle the problem yourself, you can effectively stop rust in its tracks and extend the life of your car. The process is quite manageable with the right approach and attention to detail. This guide will walk you through repairing minor rust spots, saving you a significant amount of money and keeping your car looking its best.
How Much Can DIY Rust Repair Save You?
If you’re familiar with repairing car scratches at home, dealing with rust is the next level. Professional rust repair can easily cost hundreds, if not thousands, of dollars, especially if multiple panels are affected. By undertaking the repair yourself, you can save a considerable sum, primarily spending on the necessary tools and materials.
Before we delve into the process, it’s important to set some realistic expectations:
Identifying Surface Rust
This guide focuses on repairing surface rust. If the corrosion has penetrated deep, creating holes in the bodywork, chassis, or sills, professional intervention and welding are necessary. We are addressing rust that is visible on the surface panels and hasn’t yet compromised the structural integrity of your vehicle.
Paint Considerations
This guide will take you through the preparation stages up to priming the affected area. If you’re comfortable applying paint yourself, you can certainly proceed. Solid colors are generally easier to achieve a good finish with, while metallic paints can be more challenging to blend seamlessly. Consider completing the prep work yourself and then having a body shop professionally paint and blend the repaired area for a factory-quality finish. Professional spray equipment is designed for even application, which is difficult to replicate with aerosol cans.
Step-by-Step Guide to Repairing Car Rust Spots
Modern vehicles are significantly more rust-resistant than older models. However, if you live in coastal areas or regions where road salt is used extensively, rust can still develop prematurely. Minor rust on non-structural parts is easily manageable and, with careful execution, can be made virtually invisible.
While classic car restoration often involves cutting out rusted sections and welding in new metal, for everyday cars, fiberglass epoxy and body filler offer a simpler and effective solution. Building on our previous guides, like fixing car paint scratches, let’s address rust that originates from neglected scratches or paint chips.
Rust often begins from minor paint damage, such as stone chips or door dings that expose bare metal. Regular car washing and inspections are crucial. Promptly applying touch-up paint to minor chips can prevent rust from forming in the first place, saving you significant repair work in the future.
Follow these steps to effectively repair rust spots on your car:
Tools and Materials You’ll Need:
- Angle grinder with flapper wheels (various grits)
- Wire brush
- Fibreglass epoxy gel
- Body filler
- Sandpaper (80, 400, 600, 1000, 2000 grit)
- Sanding block
- Primer
- Base coat car paint (matching your car’s color)
- 2k clear coat paint (aerosol can)
- Masking tape and paper
- Rubbing compound
- Mineral spirits or degreaser
- Rags
- Tack cloth
- Safety Glasses
- Gloves
- Dust mask or respirator
Step 1: Preparation and Safety
Before starting, ensure you are working in a well-ventilated area. Wear safety glasses, gloves, and a dust mask or respirator to protect yourself from dust and fumes. Clean the area around the rust spot thoroughly with soap and water, and then degrease it with mineral spirits or a dedicated degreaser to remove any wax, grease, or contaminants. Mask off the surrounding paintwork with masking tape and paper to protect it from accidental damage during sanding and grinding.
Step 2: Remove the Rust
The key to successful rust repair is complete removal. Attach a flapper wheel to your angle grinder. Start with a coarser grit to aggressively remove the surface rust. Work outwards from the center of the rust spot, using light pressure to avoid damaging the surrounding good metal. Keep the grinder moving to prevent overheating the metal. For tighter spots or areas where an angle grinder is difficult to maneuver, use a wire brush, either manual or powered, to scrub away the rust. Continue until you have removed all visible rust, reaching clean, shiny metal.
Step 3: Apply Fibreglass Epoxy
Once the rust is removed, clean the area again with mineral spirits and a tack cloth to remove any dust particles. Apply fibreglass epoxy gel to the bare metal. This step is crucial as fibreglass epoxy is waterproof and will prevent moisture from reaching the metal again, inhibiting future rust formation. Follow the manufacturer’s instructions for mixing and application. Apply a thin, even layer over the entire area that was rusted, extending slightly onto the surrounding clean metal for good adhesion. Allow the epoxy to cure completely as per the product instructions.
Step 4: Sand Down the Epoxy
After the fibreglass epoxy has fully cured, it will likely be uneven. Use 80-grit sandpaper on a sanding block to carefully sand down the epoxy to roughly match the contour of the surrounding panel. The goal is to create a smooth surface for the body filler to adhere to. Be patient and work gradually, checking the smoothness frequently by running your hand over the area (wearing gloves).
Step 5: Apply Body Filler
Mix the body filler according to the manufacturer’s instructions. Apply a thin layer of body filler over the sanded epoxy, using a plastic spreader. The body filler is used to achieve a perfectly smooth and level surface, blending the repaired area seamlessly with the original panel. Apply in thin layers, allowing each layer to harden slightly before applying the next. Avoid applying too much filler at once, as it can be harder to sand and shape.
Step 6: Sand the Body Filler
Once the body filler is completely dry, begin sanding it using 400-grit sandpaper on a sanding block. Sand in smooth, even strokes, following the contours of the car panel. The aim is to shape the filler to perfectly match the surrounding bodywork. Gradually refine the surface, moving to 600-grit sandpaper to remove finer scratches. Continue sanding until the filler is smooth and flush with the surrounding paint. Clean the area with a tack cloth to remove sanding dust.
Step 7: Primer Application
Apply several thin coats of primer to the sanded area, allowing each coat to dry according to the primer manufacturer’s instructions. Primer provides a uniform base for the paint to adhere to and helps to further smooth out any minor imperfections. Lightly sand the primer with 1000-grit sandpaper after it has dried completely to create an ultra-smooth surface for painting. Clean the area again with a tack cloth.
Step 8: Paint and Clear Coat
Apply thin, even coats of your car’s base coat paint, matching the original color code. Apply several coats for good coverage, allowing each coat to dry slightly before applying the next. Once the base coat is dry, apply 2k clear coat paint in the same manner. Clear coat protects the base coat and provides a glossy, durable finish. Allow the clear coat to dry completely, ideally overnight, in a dust-free environment.
Step 9: Finishing and Polishing
After the clear coat is fully cured, you may notice slight imperfections or overspray. Use 2000-grit sandpaper and water to lightly wet sand any imperfections. Follow this with rubbing compound and a soft cloth to polish the repaired area, blending it seamlessly with the surrounding original paintwork. Work in small circular motions and gradually increase pressure. Finally, apply a good quality car wax to protect the newly repaired area and enhance the shine.
Conclusion
Repairing rust spots on your car yourself is a rewarding and cost-effective way to maintain your vehicle’s condition and appearance. By following these steps carefully, you can effectively eliminate rust and prevent its return, prolonging the life of your car and saving yourself a significant amount of money compared to professional body shop repairs. With patience and attention to detail, you can achieve professional-looking results and keep your car looking its best for years to come.
