Livestream Transcript
So today’s topic is a question I’ve been asked all my life, well, all my detailing life. Can a DA polisher or a random orbital polisher be used to remove sanding marks? For example, this 1992 Chevy just got a custom paint job. It’s got a lot of orange peel. We’re going to sand it down and buff it out. So the question is, could we use a DA polisher like a Porter Cable or a Griot’s or a Rupes? And the short answer is yes. Any polisher that has the ability to remove swirls, scratches, water spots, and oxidation could also pull out sanding marks.
When Is It Efficient to Use a DA Polisher to Remove Sanding Marks?
The contributing factors as to whether or not it would be an efficient process would be some things that maybe are out of control, like how hard or how soft the paint is, how deep or how shallow the sanding marks are. If you finish out at fifteen hundred grit, it’s going to be a lot harder to pull those sanding marks out than if you finish out with Trizac five thousand grit. So, um, and then there’s of course the efficiency and the time. You know, if it takes longer, then it’s going to take longer to do the entire project.
Demonstrating Sanding Mark Removal
So what I’m going to do is I’m going to do a little demonstration here. This is fresh paint. This is a single stage. This is All Grip. Technically, it’s a paint that was made for the aircraft industry, but it’s also used in the marine world. My son-in-law built this truck, painted it himself. He chose this acrylic enamel All Grip, single-stage jet black paint because he’s smart enough to know in Florida, exposed to the sun and also extreme, you know, weather—the rain—clear coats will tend to fail over time. If you’ve got a single-stage paint, you don’t worry about clear coat failure. The worst thing that will happen is you’ll get oxidation, and of course, you can always buff that out, so I thought that’s pretty wise on his part to choose something that he can maintain for as long as he owns this car.
Sanding Process
But we’re gonna start out and I’m gonna—I sanded this thing down. So I hand-sanded this with one thousand grit to knock down the orange peel using a hard block. Then I switched—I hit one thousand and twelve hundred. Then I switched over to fifteen hundred with the medium density block. And then I re-sanded with fifteen hundred, all by hand. Then I machine-sanded dry using fifteen hundred Eagle Abrasives, and there’s actually a Flex cordless DA sander. And then I finished out with Trizac three thousand. So this has been through an extensive, multiple-step sanding process, and the end results are three thousand grit from damp sanding.
Removing Sanding Marks by Hand
But the first thing I want to do is I just want to show you that to kind of answer the question, can you pull sanding marks out using a DA? I can pull them out by hand. It’s not going to be fast, might not be as pretty, but it’s one of the things I teach in our classes, because sometimes you’ll get sanding marks in a place where it’s really hard to get in there with a spinning pad of any type. So I’m just going to—this is some NSP 95, this is a microfiber applicator pad—and the way you would pull sanding marks out by hand is you’ve got to do something I call put a little passion, that’s elbow grease, a little passion behind the pad. So you don’t just apply it like this, you got to get down and rub hard.
Okay, there’s about, I don’t know, twenty seconds of hard rubbing. Let’s go ahead and wipe off. And there you go. So back to the question, can you use a DA polisher? Heck, if I can use my hand, that answers the question—yes, you could use a DA. The question is always the efficiency and the speed.
The Traditional Approach
So let me go ahead and show you the traditional approach. So the traditional approach used by body shops and detail shops is to use a wool pad on a rotary polisher. And I’m just going to buff a section out here. Then I’m going to flip over to that side. I’ve got a Rupes Bigfoot 15 set up with one of their wool cutting pads. And when I’m done, I’ll have Yancy come down here and just show you that, yes, in fact, the sanding marks have been removed.
Paint Condition
Okay, here we go. Now, this paint was painted this last Saturday, so this is the definition of fresh paint. The rest of the truck was painted a couple weeks ago. They repainted the hood, though, because it had some paint defects they just were not happy with.
Inspection and Additional Polishing
Okay, let me give that a quick inspection. And here you can see the black single-stage paint coming off. Again, this is a paint called All Grip, and it’s used, I was told it was developed for the aircraft industry, but it’s also used in the marine industry. Okay, from what I can tell, in this section here, one hundred percent of the sanding marks have been removed. I’m going to go ahead and polish a little bit just so it’ll look a little bit better on the camera.
Do you want me to come in?
Wait until I’m done polishing. Wait until I do both.
Three-Step Polishing Process
Okay, here we go. That was just eight textbook-style section passes. And we’re gonna put this through a three-step polishing process when we do the entire truck. So we’re gonna cut it, then we’re gonna polish it twice, because it is black paint. We do want that flawless show car finish.
Finishing with a DA Polisher
Okay, so that’s one side. That’s using a traditional rotary wool pad. And let me go ahead and just clarify that for the camera. But wait to come in here after I do the other section.
I need to get that just a little bit more perfect for you for a camera on there. So I found this paint being single-stage, it just tends to react a little bit better using a free-spinning tool. And because I’m gonna be using the Rupes over there, I’m just gonna bust out my little Porter Cable here. And this is a free-spinning tool, obviously, and we’ll see if it just leaves a little bit nicer finish.
Advances in Technology
So one of the things that I also just wanted to point out is pad technology, abrasive technology, and tool technology has really come a long way. And that’s one of the things that will enable a DA polisher to pull out sanding marks and of course also finish out show-car ready.
Demonstrating the Rupes Bigfoot 15
Mucho better. Mucho better. Wow. So at some point, Yancy, you can capture the orange peel over here and then show the difference that a multiple-step sanding process by hand and by machine will get you when you’re trying to remove orange peel.
I have a couple oranges here just in case people don’t know what orange peel is. When we talk about orange peel in paint, it means after the car was painted, the paint set up and dried in a way that has a texture that looks kind of like an orange peel. So that’s where the term comes from if you’re not familiar with that.
Rotary Polisher vs. DA Polisher
Okay, so, that side was rotary polisher followed by orbital polisher. And I did this exact same process to both sides of this, exactly. So this is the Rupes Bigfoot 15. And this is their aggressive wool cutting pad for DAs. And it looks like I got it—let me make sure it’s completely centered here.
It’s really important anytime you’re using a random orbital to absolutely get that pad centered. Okay, and then when using a microfiber pad like this, it’s important to prime that pad so a hundred percent of the face of that pad is coated with abrasives. And then after you’ve done that, then you can go ahead and add like three pea-sized drops just so you have some, what I call, working product.
The Kevin Brown Method
Years ago, there was a guy—his name’s Kevin Brown. He got all this fame and glory for coming up with what they call the KBM, the Kevin Brown Method. And it’s basically doing this, taking your finger or some sort of implement and cutting the fibers. And it’s a good practice, it’s a good technique. And the idea being when you turn this on, a hundred percent of those fibers are cutting for you. You’re being as efficient as you can.
Okay, so then… There’s my three pea-sized drops, and again, I’m just gonna work a little section out here. Okay, I’m gonna turn this to the low setting to spread this out.
Working with the Rupes DA
Okay, that is the five-speed setting. And if you look, I’m maintaining really good pad rotation. And that’s key when using a free-spinning random orbital polisher. You want to maintain good pad rotation and good pad oscillation. Again, you can see some of that single-stage black paint coming off on that pad. That was a brand new pad. Wow, that looks good. That actually looks really good.
I’m going to go ahead and do a little polishing work to it too. This is kind of the cool thing—if you’re pulling sanding marks out with a DA polisher or what’s called a random orbital polisher, you can both cut and polish with the same tool. These are the Rupes contour profile pads—really nice pads. Rupes did a great job when they developed these pads. The thing I like about them is that contour profile—what it does is it allows the pad to mushroom or squish back versus twist in if they didn’t have that contour profile there.
Okay, let me turn my speed down, spread this product out. And come up to, there’s the four. And one of the things I like about the Rupes tools is they’re so well-balanced. This is three. There we go. Six. Seven. Lighten up on the pressure to finish out. There’s eight textbook section passes.
Finishing Touches and Clarifying the Paint
Okay. That looks good. One second here before we bring the camera over. I’m going to wipe the splatter off of this side. Not supposed to splatter, but I did. Clarify this side. This is a new product that Jim sent me to test out here at… Ooh, new product. Clarifies the paint. This actually still looks just a little hazy. Let me switch over to a finishing pad. Again, this is the first time I’ve ever worked on this.
So we’ll pull off—that’s the Rupes Yellow, their polishing pad. And this is their fine finishing pad. And it just could be this paint is a little bit on the finicky side, which I imagine is just because it’s single-stage. So one of the things about working on single-stage, unlike a clear coat, is you’re actually working on the pigments, and that does affect the appearance and how the products all work too. Kind of the same thing with working on gel coats. When you’re working on gel coats, pigment makes a big, has a big influence on how a gel coat sands, cuts, and polishes.
Time for a Close-Up
Okay, that should get it. It’s hot out here in Florida today, so I’m burning up. Oh, much better. Okay, I’m just gonna—I want to treat both sides equally, so I’m just going to hit this a little bit of this clarifier and glossing product.
Okay, Yancy, you want to come in and…
Time for a close-up? Yeah, I want you to—let me get the splatter off this fender. I think if you come over here, and I can keep my finger here, put the orange here, so you can really capture the level of orange peel. And then when you move over, you can see the lines in the overhead lights now. They’re very distinct. And that’s what you’re looking for in a show car finish. It’s what they call DOI—distinction of image.
Put your finger down on the… like right here. There’s also a lot of DIP, dirt in paint. Come over here. Okay. Right in the middle. Okay. Are you capturing the overhead lights? I’m capturing the reflection. Oh, okay. Because you can get it from this side too.
The Orange Peel Comparison
Okay, then right here. I’m leaving these beautiful fingerprint smudges. There you go. And if you want to try it from this side here. Yeah, this thing. We were making a joke earlier—the orange peel in this is so bad it’s not orange peel, it’s grapefruit peel.
Now look at the distinction. Let me put my finger down, look at the distinction of image just by sanding and buffing. How beautiful that paint came out. So there we just proved it that yes, you can in fact pull sanding marks out using a DA polisher.
Paint Hardness and Efficiency
And again, the primary factors that would affect how fast or how efficiently you can do this would be the hardness or the softness of the paint, and that’s always an unknown factor until you get in and start doing some testing.
Yesterday, when this truck arrived, I did some sanding with 1500 grit. And even though sanding is not a super good way to test how hard the paint was, I kind of find it to be on the medium side. It wasn’t like super hard—it was sanding good. But when I tried to pull the 1500 grit sanding marks out with the wool pad, it was kind of tough. So that kind of told me that the paint would be more on the medium hard side at least.
Final Thoughts on Sanding
Then the other thing is, how high do you want to finish out at? For example, for this, I finished out—I started with one thousand grit hand-sanding, went to twelve hundred hand-sanding, went to fifteen hundred hand-sanding, went to machine-sanding with fifteen hundred to refine my hand-sanding marks by with machine marks, and then I did a final section pass on there using the 3M Trizac damp-sanding.
So I left a fairly shallow sanding mark pattern, and that’s how I would treat any car, because I’m a big proponent of finishing out the highest grit your budget will allow, because that just makes any buffing faster, easier on you, and also cooler to the paint.
Conclusion
In the Trizac system, you could actually go to five thousand, and you actually start to polish the paint at that point, and they even have eight thousand. So again, what I always tell people that contact me and ask me about their own personal sanding projects: sand out to the highest grit that your budget will allow because some of these sanding discs that we’re using here, they’re not inexpensive, and that’s pretty blunt. Anyway, there you go.
So yeah, you can do it. Let me just add this comment, though: the only time I’m going to cut a car, I’m still going to use a rotary. One of the reasons why is because it’s really easy to do this kind of a demonstration on a panel that’s very flat. But this has a concave curve here, a concave curve on the other side. And anytime you get around edges, it just becomes more difficult to maintain good pad rotation and pad oscillation, both for fast and efficient defect removal.
But with the rotary polisher, because it’s gear-driven, you know, it’s one-direction gear-driven, you’re not going to have to worry about any pads. So to me, it’s going to be faster, more efficient. And then, you know, sometimes people will say, well, Mike, if you’re using, I mean, that finish, that side over there with the Rupes blue cutting pad, I mean, it looked good.
Rotary vs. DA for Finishing
Okay. And that’s with an orbital. The problem with the rotary, though, is every one of these fibers is going to leave this little cut in the paint, and that’s called holograms. But if you’re using great abrasive technology, the hologram depth is primarily based upon the fibers, not the abrasive technology. So it’s very shallow, so it will buff out very fast.
So for me personally, when we finish this truck out, we will sand it down and cut it with wool pads with the rotaries, then switch over to orbital polishers to perfect the paint. But if you wanted to, you could sand down a car and pull it out using an orbital polisher. Just take a little bit more time. Just take a little more time for the more complicated areas. The flat panels aren’t going to be a problem.
But again, it really depends on how high you sand out and things like paint hardness, paint softness, which are always unknown variables until you start getting in there and do some testing.
So there you go.
Good over there?
That’s it. That’s all I really had today. Like I said, I’ve been asked this question. I think I covered this before we went offline, but in 2003, I transitioned at Meguiar’s from the corporate writer. I took over all the writing duties for Barry Meguiar.
A Little History
They created a job for me called Internet Technical Specialist. That’s because this thing called the discussion forum went commercial. And so I was always teaching their classes and then answering questions on the forum. Basically, I’ve been paid to answer questions about detailing for over twenty years now. And one of the most common questions I always get is, hey, can I use a DA to remove sanding marks?
And so we just proved that, yes, you can.
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