Car Bumper Scratches

How to Fix Car Bumper Scratches: Step by Step Guide

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If you drive a lot to and from work, there’s a high possibility that you might get some scratches and dents in your car’s bumper. This is also inevitable if you love driving a lot around the city and parking your car in public parking spots. While they are not as severe as cracks and dents, car bumper scratches can be removed quite easily at home without having to spend a hefty amount of your time and money by taking your vehicle to a repair shop.

Now, some people may perceive it as an extremely difficult endeavor. But, repairing your bumper’s scuffs and scratches is easy and doesn’t demand any knowledge in rocket science to fix it. With that said, this guide will proceed to offer you a well-detailed step-by-step procedure on how to fix and repair car bumper scuffs and scratches.

But First, What Not to Do

Following recent technological advancements, most car bumpers today are made of plastic and fiberglass. Repairing scratches from such bumpers has become easier as you only need to do some sanding, painting, sculpting, and finally, painting.

Now, to be honest, this DIY project does demand some time but in the end, it’s worth the effort. To avoid this hassle, most car owners end up doing what they shouldn’t—they head straight to their local auto parts stores to get some cheap body fillers and matching paint. This is a bad idea!

The truth is, the technology behind car body parts has changed and you too (the driver) should adjust to it. While traditional metal bumpers were easy to repair, today’s plastic and fiberglass bumpers will demand you to collect an array of supplies before you can proceed to fix it.

How to Repair Plastic Bumper Scratches

Step 1: What Do You Need?

Before you commence with the process of turning that scratched bumper into something beautiful, you’ll need to put your supplies in order. You will require;

  • Factory quality paint
  • Automotive clear coat spray
  • Spray primer
  • A fine and coarse sandpaper
  • A prep solvent for removing oils and dirt
  • Scuff pad
  • A microfiber towel or generally a clean cloth
  • A grease/wax remover
  • Putty for filling scratches
  • Safety gear such as gloves and glasses

Step 2: Cleaning the Bumper

Start off by cleaning the bumper itself to get rid of dirt, oils, grease, tar, and wax. When it’s clean, dry it thoroughly before wiping it once more with a prep solvent. This will not only remove excess oils and dirt from the bumper but will also help to promote adhesion.

Note: when wiping the repair area with the prep solvent, only go in one direction but not to and fro as this can drag contaminants back to the scratched areas.

Step 3: Isolate the Scratched Area

Next, ensure that you isolate the area you’ll be working on to avoid damaging other parts of the bumper. You can simply do this by sticking old newspapers or adding masking tape to other parts of the bumper. If you’re a fan of ER, this is similar to what surgeons do when they’re operating on a patient.

Step 4: Let the Sanding Begin

Now, this is where the repair work begins. But, before that, there are two things you need to be aware of. First, you need to check the severity of the scratches, and second, confirm the model of the bumper to identify which type of plastic it’s made of.

You can do this by checking the label stamped on the backside of the bumper. Since bumpers are not the same, knowing the type of bumper you’re repairing will help you to order the appropriate repair kit from an automotive store.

Some of the labels you’ll come across are;

  • PP (Polypropylene)
  • PPO (Polyphenylene Oxide)
  • TPE (Thermoplastic Elastomer)
  • PUR (Polyurethane Plastic Rigid)
  • TPUR (Thermoplastic Polyurethane Elastomer)

With such information at hand, you can now get ready to sand the scuffed or scratched surface of your car’s bumper. If the scratches are minor, you can use 400-800 grit sandpaper and if they’re severe, you can use 100-200 grit sandpaper. When sanding, you’ll need to maintain a consistent firm pressure until the scratches are smoothed entirely.

Step 5: Fill the Scratches

If the scratches are unable to disappear by sanding, then you’ll have to fill the scratched areas with a polyester filling putty. Here, mix equal amounts of the hardener and repair adhesive on a clean board then use a spreader to smear the putty mix on the scratched sections of the bumper.

Apply the putty mix firmly and evenly with a lot of consistency to increase adhesion and prevent possible air entrapment.

When you’re done, wait for at least 30 minutes for the putty mix to dry or according to the speculated time as indicated on the instruction sheet. When the putty has dried, sand the scratched section of the bumper gently using 80 grit sandpaper to smooth the surface and remove any debris.

Next, use 120 grit sandpaper while applying a light coat of the repair material. This will help you to fill any imperfections on the bumper while allowing it to restore its original contour. Finally, sand the surface with 400 grit sandpaper before cleaning it thoroughly.

Warning! Since repair adhesives and fillers cure within a fairly low range of temperatures, you will require a warm dry place to accomplish the repair process. Additionally, avoid working in basements or garages with low air circulation as automotive chemicals can give off noxious fumes that can be harmful to people with respiratory illnesses.

Step 6: Apply Primer to the Surface

When the surface is fully dried, apply two coats of wet flexible sealer and wait for about 30 minutes for it to dry up. Here, you might need to cover your nose with a mask as these paints can be toxic when inhaled.

Now, to apply the primer/undercoat, you will need to spray three coats while allowing 15 minutes for each coat to dry up. Ensure that you keep a distance of about 15 centimeters to allow a smooth and even application. When you’re done spraying all three coats, allow the surface to dry out naturally for about 8 hours.

Step 7: Sand It once More

Once the primer has entirely dried up, you’ll have to sand the surface once more to remove any small particles that might be present in the area. A 400 grit sandpaper is the perfect one to use as it will sand the edges making the area smooth and satisfying.

Step 8: Painting Time

Now that you’ve followed all the previous steps carefully, it’s time to paint the bumper to give it a completely new look. But, before doing that, make sure that you examine the color of the paint to ensure it’s exactly the same as that painted on your car.

Note: using paint with a different shade as compared to that on your bumper can easily mess up the appearance of your car.

Start off by cleaning the surface gently using a wet towel to remove any particle leftovers. Once dry, apply the first coat by spraying gently at a distance of about 10 centimeters. Do this with the rest of the coats (about 3 coats) and don’t forget to maintain consistency.

When you’re done with the paint, mix the clear coat with the hardener to get ready for the final step. The clear coat is a transparent paint that acts as a protective layer to ensure that the paint stays long without peeling off.

Just like the prime and the paint, spray the clearcoat at least 10 to 15 centimeters away while allowing 15 minutes for each coat to dry up. When you’re done, double-check the surface carefully to ensure it’s smooth and perfectly finished. In case there’s any overspray left out on the surface, you can apply a blending solvent to remove it.


Final Verdict

If you have followed these steps carefully, then congratulations! You’ve just removed scuffs and scratches from your car’s bumper to make it new again. Although this process is lengthy, following it to the latter means that the final results will be fruitful.

Most people, especially those with less knowledge about vehicle parts, will prefer to visit their nearest auto repair car stores to have their cars fixed by the mechanics. Although this isn’t a bad idea, one drawback is that you’ll end up spending a lot of your time and money.

On the other hand, doing it yourself is a lot cheaper as you’ll end up keeping all the leftover repair products till the next time your car’s bumper demands another repair.

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