How to Clay Bar a Car

Categories: Paint, Product Reviews

Unless you’re a real detailing obsessive like me, this is probably the first time you’ve heard of a Clay Bar since Gumby had his very public struggles with alcoholism. It’s not something most people know to do, or why it’s so useful. Well, we’re changing that now. Today, you’re learning how to clay bar a car.

First, the why. Your car’s paint is like its skin, a protective layer taking the full brunt of the elements and keeping the steel and aluminum underneath from rusting and oxidizing. And obviously the paint is the first thing anyone notices when they look at your car, so keeping it looking healthy and youthful will pay off big come time to sell or trade it in.

Modern automotive paint comes in multiple layers: primer, color coat, and clearcoat. It’s this top transparent layer that does most of the heavy lifting. It’s the one interacting with the atmosphere and road grime, bird droppings, and takes the brunt of the sun’s UV-A and UV-B rays. Clearcoats, plus better paint formulations, are why colors don’t fade as fast or as much as they used to. The trouble is literally everything on the road is working overtime to screw it up.

Thoroughly Ruined Paintjob on the Hood of an Impala

Believe it or not, the rot in the above hood started life as simple water spots and tiny bits of road tar. When raindrops on your paint evaporate, they leave behind dissolved minerals that collect at the edges of the droplets due to surface tension. Left in place, these deposits begin interacting chemically with the clearcoat, starting the process of breaking it down. The same is true of acidic bird droppings, bits of road grime, tar, and brake dust.

Not even a thorough handwashing will remove all of these contaminants. Given enough time, the clearcoat’s deterioration is inevitable. But fear not, that’s where the clay bar comes in. Let’s dive into the how, and then we’re finishing with the importance of waxing your car as a final step because I went yard on detailing purchases this month and need to justify them to my wife.

I may have gone a little overboard

Making Clay

Before you do anything, wash your car. By hand in your driveway, at the carwash, doesn’t matter. Just wash your car. I’m going to assume you’ve washed a car before and don’t need a 1,500 word blog post to explain the process. S’ok? S’alright. Moving on.

You’re all familiar by now with my affinity for Mothers products, but it’s just personal preference. There’s a lot of options out there and really, this isn’t rocket science, so they’re all fine choices. This particular kit covers everything you need. Clay, spray, and microfiber cleaning towel.

The idea of a clay bar is removing the small but sticky particles of dirt and grime clinging to your paint without damaging it in the process. That’s where the spray comes in.

Gotta Keep it Wet

The detailing spray acts as a lubricant, maintaining a thin but important layer between clay bar and clearcoat. You don’t want to use water in this role, you need a surfactant with low surface tension. The detailing spray is formulated for the task. The clay bar glides over this layer, picking up the bits of dirt and grime and pulling them free without ever coming in direct contact with your clearcoat.

Which is why you want to keep it wet. Ideally you’re doing this in a garage, but if not try to pick a cloudy day to keep things cooler. Work one panel at a time, like a hood or roof, and be generous with the spray. Apply an even, total coat across the area you’re going to work. You don’t want any dry spots. With a normal sized passenger car you’re probably going to use an entire bottle of this size in a single job.

Light, Even Pressure is Key

Once you’re lubed up, just take the provided clay bar and gently drag it across the surface of your paint. Keep it flat and even, and don’t apply much downward pressure at all. Let the clay catch and trap the particles. I usually do two passes on each panel, one vertical, one horizontal. It won’t take very long at all before you see what’s been hiding in plain sight.


The dirt trapped in this brand-new clay bar is from just one half of the hood of my car, which remember was freshly and thoroughly washed not even half an hour before. Any of those little bastards could have become a focal point for deterioration given the chance. But they can still cause scratches on the next panel. Trap them deeper in the clay by kneading it frequently, then flattening it out again before resuming the process. When you’re finished with a panel, use the microfiber cloth to wipe up the excess lubricant.

This is what the clay looks like compared to new after doing just one car, one time. Clay can be reused many times so long as you’re mindful about kneading it enough, so don’t throw it out just because it’s dirty. Store it in a Ziplock bag to keep it from drying out between jobs.

Now you have a properly clean car ready for the next step in our little paint preservation care clinic.

Wax on. Wax Off.

Now that your car’s clearcoat is truly clean and smooth, it’s time to lay down an extra layer of protection from the elements conspiring against it. Wax doesn’t just add deeper luster and shine to your paint. It fills micro-scratches and swirl marks, and acts like a full-body condom to keep all the things trying to corrupt your paint safely away.

I’ve opted for the most extreme option, because anything worth doing is worth going truly overboard. Mothers has a three-step “Ultimate Wax System” that starts with a polish, moves to a glaze, and finishes with pure Brazilian carnauba wax. Is it overkill? Yes. Do I care? Absolutely not.


Folks, I’ve waxed a lot of cars, a lot of times. You can do a hand wax. If you hate yourself. There’s no reason or benefit to hand waxing unless you’re about to roll out a multi-million-dollar, historic, one-off Le Mans racer from its trailer onto the Pebble Beach Concours d’Elegance. Which, if I’m being brutally honest with myself, no one reading this blog is doing.

Just buy a corded orbital buffer. It will save your arms and shoulders a lot of misery, and good-enough examples cost $40 or less. You don’t need professional grade because you’re only going to use it a couple times a year, and you don’t need expensive cordless, battery-powered types unless your car is parked a football field away from the nearest electrical outlet. Buy an outdoor extension cord, you’ll save a ton.

The ten-inch buffer I bought came (in a case!) with the buffer itself, two application pads, and two buffing pads. Application pads are smoother and used to lay down the polish, glaze, or wax while it’s still wet. Buffing pads are softer and used to remove the polish, glaze, or wax after it’s dried.

Dried Like This

It’s really important that the weather be bone dry while you’re doing this. Any moisture at all will make cleanup a huge pain and prolong the process.

Just like with the clay bar, work one panel at a time. Keep the applicator pad moist with polish or wax, but not soaked. Don’t press down. It’s the buffer’s speed doing the work, not pressure. Let it do the job, all you need to do is ensure complete coverage over all of the car’s paint. If you go over into the plastic trim, no big deal, we’ll address that later. You’ll quickly notice the wax drying to a cloudy haze as you move on. That means you’ve laid it down right.

Once the whole car is covered, pull the applicator pad and move to the buffing pad. Now your task is to buff away all the excess dried polish/glaze/wax until only a pristine finish remains. You may have to change buffing pads as they become fouled with excess wax. Don’t worry, you can throw them all in the laundry and they’ be good as new for many cycles. The pads aren’t going to remove everything, so have a towel standing by for one final pass. Even then, there will be enough powdery white residue for a weekend at Circa in Vegas. Especially in the body lines and trim joints.

Remember the plastic detailing brush in that Black Trim Restoration kit I told you to buy a couple blog posts ago? Well, here’s where it becomes multi-functional. The soft plastic bristles won’t hurt your paint, and they’ll clean out the wax residue in no time. Also, now would be a great time to clean and condition your black trim. It’s almost guaranteed some wax got into it, and what’s good for your paint is actually pretty bad for your trim and will dry it out if left in place.

Just Fuckin’ Look At It

When you’re finished with all this, you’ll have a finish that’s not only protected from the elements for months, but… just drink that in. It’s smooth and shiny enough to use as a mirror on NASA’s next space telescope.

You can’t have it, NASA! It’s mine!