How to Sand Out Runs in Clear Coat: A Step-by-Step Guide

Wondering how to sand out runs in clear coat? We know that dealing with imperfections in your car’s finish can be frustrating. This guide will walk you through each step to help you achieve a flawless finish.

How to Sand Out Runs in Clear Coat

What You Will Need

600-grit wet/dry sandpaper

1000-grit wet/dry sandpaper

1500-grit wet/dry sandpaper

Bucket of water

Soft cloth or sponge

Compound polish

Car wax

Step-by-step Guide on How to Sand Out Runs in Clear Coat

Here are the steps to sand out runs in clear coats…

Step 1: Assess the Clear Coat

Here’s what you’ll need to do…

Examine the Surface

Before you even think about grabbing your sandpaper, it’s crucial to carefully examine the clear coat to pinpoint the runs that need correction. Find a well-lit area, preferably natural light if possible, to get the most accurate view of the surface.

Identify the Problem Areas

As you inspect the clear coat, look for any noticeable runs, drips, or sags. Runs in clear coat can appear as vertical or wavy lines that are thicker than the surrounding areas.

Use a piece of masking tape to lightly mark the areas that need attention; this will help you focus solely on the problem areas when you start the sanding process.

Gauge the Severity

Understanding the severity of the runs will help you determine how much sanding is needed. Light runs might only require minimal sanding, whereas deeper or more extensive runs may require more time and even multiple grades of sandpaper.

Step 2: Prepare the Area

Take the following steps…

Clean the Surface

You don’t want to start sanding on a dirty surface as it could embed contaminants into the clear coat, leading to further problems.

See also  Tips for Sanding Furniture: The Ultimate Guide

Using a soft microfiber cloth or sponge, gently clean the area around the identified runs. Make sure to remove any dust, road grime, or other contaminants.

Dry the Area

After cleaning, thoroughly dry the area with a clean, dry cloth. Any leftover moisture could interfere with the sanding process and lead to an uneven finish.

Mask Surrounding Areas

If the run is close to areas that don’t need sanding, it’s a good idea to mask those sections off with painter’s tape to protect them. This ensures you are only targeting the clear coat run and not affecting the otherwise good surrounding areas.

Step 3: Wet the Sandpaper

Here’s how to wet the sandpaper…

Why Wet Sanding?

You might be wondering why you can’t just start sanding with dry paper. The reason is simple: wet sanding offers a finer finish and helps to reduce friction.

This makes it less likely that you’ll scratch or gouge the clear coat during the sanding process. It’s an extra precaution to ensure a better outcome.

Choose the Right Grit

The first sandpaper you’ll use should be 600-grit. This is coarse enough to flatten the run but not so abrasive that it will damage the surrounding areas.

Soak the Sandpaper

Take your 600-grit wet/dry sandpaper and fully submerge it in a bucket of clean, cold water. Allow it to soak for approximately 10 minutes. This ensures that the paper is thoroughly saturated, which will provide smoother movement when sanding.

Prepare a Damp Cloth

While you’re waiting for the sandpaper to soak, it’s a good time to prepare a damp cloth or sponge. You’ll use this later to wipe away sanding residue and assess your work.

Step 4: Begin Sanding

Here’s what you’ll need to do…

Start with Gentle Strokes

With your wet 600-grit sandpaper in hand, begin to sand the identified run gently. Keep your strokes linear and work in one consistent direction rather than moving back and forth. This helps to minimize any potential swirling patterns that could mar the finish.

Apply Even Pressure

The key here is to use even pressure throughout your strokes. Pressing too hard could damage the clear coat and even expose the underlying paint. On the other hand, applying too little pressure won’t be effective in removing the run.

Take Your Time

Rushing the process may lead to mistakes. Take your time and periodically stop to check your progress. Use the damp cloth or sponge you prepared earlier to wipe away the sanding residue.

This allows you to see clearly how much of the run has been removed and whether you need to continue with the 600-grit or move on to a finer grade.

See also  How to Sand a 6-Panel Door: The Complete DIY Guide

Assess and Adjust

After wiping away the residue, closely examine the area. If the run is still visible, continue with the 600-grit sandpaper until it is mostly flattened. Remember, the goal is to remove the run without damaging the surrounding clear coat.

Step 5: Check Your Progress

Do the following…

The Importance of Pausing

In a task that requires such precision, it’s easy to get carried away with the sanding process. However, pausing to check your progress is crucial.

This step is not just a formality; it’s an essential part of ensuring that you are effectively removing the run without causing further damage.

Wipe Away Residue

Use a damp cloth or sponge to gently wipe away any sanding residue. Make sure the cloth is clean to avoid reintroducing any contaminants back onto the surface. This will give you a clearer view of the area you’ve been working on.

Assess the Surface

With the residue cleared away, you can accurately assess the state of the run. Is it completely flattened, or can you still see some raised or uneven areas?

Your observation here will dictate your next moves, whether that’s more sanding with the current grit or progressing to a finer grit.

Consult Your Markings

Remember those markings you made during the assessment stage? Now is a good time to consult them. Ensure that you’re staying within those boundaries so that you’re only sanding the areas that need it.

Step 6: Move to Finer Grit

Here’s what you’ll need to do…

Why Switch Grits?

If you’re new to the world of sanding, you might question why you can’t just stick with one grit of sandpaper. Using multiple grits allows you to gradually refine the surface, ultimately leading to a smoother finish.

Starting with a coarser grit removes the major imperfections, and progressing to finer grits polishes the surface.

Transition to 1000-Grit

Once you’ve determined that the run is mostly flattened by the 600-grit sandpaper, it’s time to switch to a finer, 1000-grit sandpaper.

This grit will help to smooth out any minor imperfections and begin to polish the surface. Remember to wet the sandpaper in water for about 10 minutes before use.

Finishing with 1500-Grit

After you’ve achieved a nearly perfect surface with the 1000-grit sandpaper, make the final switch to 1500-grit to finish off. This will provide the final smoothing and prepare the surface for polishing.

Repeating the Process

Each time you switch to a finer grit, the sanding process essentially remains the same: Use linear strokes, apply even pressure, and regularly check your progress.

See also  How to Sand Masonry: Your Complete Guide to Flawless Finish

The only difference is that as the grit numbers go up, your sanding strokes can be a bit lighter since you’re now focusing on refining, not removing.

Step 7: Apply Compound Polish

After you’ve gone through the meticulous sanding process, your clear coat may look a bit dull or hazy. Don’t worry; this is normal. The next step, polishing, restores the original luster and shine to the sanded area.

Choose the Right Compound Polish

There are numerous types of compound polishes available on the market, each with its own benefits and recommended uses. For this task, opt for a high-quality compound polish designed for automotive use.

Application Technique

Take a soft cloth, such as a microfiber cloth, and apply a small amount of the compound polish onto it. Gently rub the cloth in circular motions over the sanded area.

The objective is to spread the compound evenly, filling any microscopic imperfections left from the sanding process.

Buff to Shine

After you’ve applied the compound polish, use a clean section of the cloth to buff the area gently. This further smooths the compound and begins to reveal the renewed shine of the clear coat.

Step 8: Wax the Area

You might wonder if waxing is truly necessary after polishing. The answer is yes, especially if you want to seal and protect the freshly sanded and polished clear coat. Waxing provides a protective layer that guards against environmental factors like UV rays, dirt, and moisture.

Choose Quality Car Wax

Select a high-quality car wax that is compatible with your vehicle’s clear coat. Check the product label or consult with professionals to make the right choice.


Apply a small amount of wax onto a new soft cloth. Gently apply the wax in circular motions, just like you did with the compound polish. Make sure you’re only targeting the sanded and polished area to maintain consistency.

Buff and Seal

Once the wax is applied, use another clean cloth to buff the area. This removes any excess wax and helps to seal the clear coat. Your buffing motions should be gentle and consistent, ensuring the surface is both shiny and protected.

Final Inspection

After buffing, step back and admire your work. You should see a restored, run-free clear coat that shines like new. If all looks good, you’ve successfully completed the process of sanding out runs in clear coat.

For more articles on sanding, click here: Sanding: Your Full-Circle Guide to Smooth Mastery


Addressing runs in your vehicle’s clear coat may initially seem like a daunting task, especially if you’re not familiar with automotive detailing.

However, as we’ve walked through each step, from assessing the clear coat to the final waxing, it becomes evident that this is a manageable project that can yield professional-level results.

By approaching each phase with care and attention to detail, you not only rectify the imperfections in the clear coat but also restore its original shine and protect it for the future.

Remember, the key to a successful outcome is to be methodical and patient. Don’t rush through the steps; take your time to assess, prepare, sand, polish, and finally wax the affected area.

Quality products and the right techniques are your allies in this venture, helping you achieve a restored, beautiful clear coat.

By understanding and following these steps, you equip yourself with the knowledge and confidence to tackle similar issues, should they arise in the future. Here’s to many more years of a gleaming, well-maintained vehicle!

Leave a Comment