How to Sand a Car Before Painting

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You might have done some painting in the past; like painting a wall, painting wooden furniture or even your ceiling.

Well, great! It is quite a different thing for you to paint a car and that is why you need a handful of guidelines on how to sand a car before painting. It is arguably the most crucial stage of the repainting process.

The first thing you need is time; you need to create time for it. As for materials, you will need 1,200 – 2,000 grit wet-and-dry sandpaper or an excellent sanding machine, abrasion-resistant film.  You will also need abrasive discs if you are using a sanding machine.

So let’s quickly move into the process proper:

What is Sanding?

Simply put…

…Sanding is one of the most critical aspects of paint preparation for a car, and it helps to remove the top layer of a car’s paint with the use of abrasive materials.

It’s important to invest all the time to do it properly to get the best possible results. Sanding can be done with either an electric orbital sander (like the one here ) or sandpaper, depending on the job, and you’ll also need to use different paper grades depending on the task.

Recommended Reading: How To Get Rid Of Roller Marks When Painting

How to Sand a Car Before Painting

a worker sanding a car for painting
auto mechanic worker applying washing car body preparing for painting at automobile repair and renew service station

1. Preparation of the Surface

Before you begin the sanding process, you should start by removing any obstacle, as they will only make the job harder. By obstacles, I mean any dust, grease, or road grime. Of course, this can be quickly done by washing the car.

Also take off any loose fittings on the car’s body or any attachments like the side mirrors, headlight covers, and the badges. In short, remove all that can be removed. Everything else should be masked with the abrasion-resistant film.

Recommended Reading: Best Automotive Paint Gun for Beginners 

2. Fix the Dents and Scratches

Next thing to do is that you should take care of any visible dents or scratches (whether deep or just a slight one). If you are going to make use of a filter, be sure that you get excellent adhesion.

This can be done easily by cleaning the inner part of the dent, the scratch or the chip (if present), which creates a rough surface, of course with the use of the abrasive.

3. Get the Sanding Machine Ready

sanding car before painting

Now that the car’s exterior is all prepped up, you can now attach the coarse abrasive disc onto the sanding machine. You can use the P60 grade for the first sanding process.

Do not get carried away by the sound the sanding machine produces; there is a pattern you must follow. You should not just use it anyhow.

You should start by using a smooth circular motion to remove the clearcoat, the topcoat, and the base coat completely. When sanding using the smooth circular motion, do not stop and also do not move too fast.

For you to reach the corners of the car’s body parts correctly, you would have to sand with your hand using sandpaper (watch the video below). If the coarse attachment cutting is turning out to be too hard, change to a lower grade.

For you to get the best result, sand the entire body till you get a perfectly smooth surface for the primer to adhere to.

It will take more time if you are using sandpaper, but make sure that you sand the entire surface as smooth and even as you possibly can.

4. Change the Abrasive Disc

Once you sand to the point where you get to the primer, change the coarse disc you started with and switch to one with the more delicate surface.

The essence of this is to completely get rid of the scratches that must have resulted from the initial sanding with the coarse disc.

Ideally, you must get to the bare metal, so you should continue to remove the primer as much as possible.

5. Finish it up!

One of the importance and purpose of the whole sanding process does not only make the surface of the car’s surface free from unwanted particles, but it is also to make the surface ready to have enough grip for the primer and the paint.

As a quick reminder, the best practice on how to sand a car before painting it is to remove the former paint and primer to get down the bare metal.

This will make ensure the finish is more even and provide a stronger and more durable adhesion when the new primer and paint is applied.

Finally, you are doing this indoors, make sure the floor is adequately swept, and there is enough space for you to work. Avoid any form of obstacles.

And if you are working outside, do it where there is no too much dust particles or other contaminants. And now, your car’s body is ready to get painted.

Recommended Reading: Top Rated Paint Sprayer for Cars

Watch the short video below for a better understanding of the process of sanding a car before painting:

Sanding a Car Before Painting | Conclusion

Why should you hire a professional who would charge you exorbitantly for a job that is cheap and easy to do? Painting a car is not as hard you may have thought.

If you wish to learn how to sand a car before painting, this post is the complete information you need to help you achieve your desired goal.

Getting the necessary materials will be more cost-effective for you than trying to get a professional. Give it a try now and see how much you could save in the long run.

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