Wet sanding with Dual Action Polisher

[TwinSport]

Hi folks!

Since my parent's cars have some deeper defects which I cannot remove with abrasive polishes only, I bought some wet sanding paper.

Yesterday was the day to try it out.

I took the old grille of my father's Astra OPC, as seen here:


I washed and clayed it first to achieve this.


Because there was not even 1 deeper scratch I decided to create some by using a knife.


And here they are: deeeeeep!




One day before I put the wet sanding paper in a bucket with water and a bit of Meg's Last Touch.
So I went on with 2500 grit and the Megs backing pad. As lube I took Last Touch 1 : 4 water. Be sure to always use enough water! The surface must be really wet. Always move in straight lines and do not apply too mich pressure to the pad, let the paper do the work. After a few passes dry the surface so that you can see if you may already have removed to much of clearcoat!

When it's time to stop wetsanding, the surface dry looks like that:





Some people say you can't remove those sanding marks with a Dual Action Polisher, but that's wrong information. With my Megs G220, a Megs Cutting Pad and Menzerna IP 3.02, I achieved some good results after 2 passes of polishing.

Results:









Exatcly the way I excepted it to be. Scratches are still there but since the edges of the scratches are rounded and the light is now being broken expanded the human eye can't catch the scratch that easyly.
So it's still there but you can only see it by looking closely at it. As you may see, I was not able to catch the scratch with my camera.


Best regards,
Sebastian

[Mike Phillips]

Re: Wet sanding with Dual Action Polisher

While the above appears to have worked in this situation, we need to clarify a few points.

1) As a blanket statement, D/A Polishers were not designed to remove sanding marks and are not the best/preferred method of remove sanding marks. There are so many variables to deal with on paint; therefore Meguiar's does not recommend using a D/A Polisher to remove sanding marks. While it appeared to meet the above expectations in this example for this forum member, we do not want anyone trying this process on an entire car. You could easily get yourself into trouble.

2) When you get into sanding and removing serious defects you are in an entirely new realm. You have many many factors to consider.

• Expectations
• Hardness of paint
• Freshness of paint
• Type of paint
• Age of paint
• Condition of paint
• Thickness of paint
• Your skills, experience and abilities

Just to name a few. These factors are going to determine what liquid, pad, technique, speed, pressure, & RPM’s (rotary) to use. It may even determine if you even sand the surface to begin with.


3) To sum it up nicely, wet-sanding/color-sanding is easy to do, but very difficult to master, and we do not want anyone to get themselves into trouble by simply expecting every surface to turn out perfect by sanding and using a D/A Polisher to restore the finish.

If there are any users with experience, please feel free to chime in with your thoughts and experience...

We've held three Advanced Classes so far this year on wet-sanding and using the rotary buffer to remove sanding marks... perhaps some of these forum members that now have had first-hand experience using the proper tools and techniques to wet-sand and then remove the sanding marks will chime in with what they learned from the class in the context of duplicating these types of procedures only using a DA Polisher instead of a Rotary Buffer.

[Mike Phillips]

Re: Wet sanding with Dual Action Polisher

A few more comments for everyone that will read this into the future as Meguiar's and Meguiarsonline.com plan on being here for a long time...

Some people say you can't remove those sanding marks with a Dual Action Polisher, but that's wrong information.

Best regards,
Sebastian

An experienced person with the right products can use a DA Polisher to remove scratches sometimes on some paints, but not all the time on all paints.

That doesn't mean everyone can remove sanding marks using a DA Polisher and it would be irresponsible for Meguiar's to let anyone read this thread and walk away thinking they could wet-sand their entire car and then remove ALL the sanding marks using a DA Polisher based upon information posted to this forum.

Unlike most other detailing discussion forums, on this forum we are held accountable as to the accuracy of the how-to information our employees post and also the accuracy of the how-to information our forum members post and we take this serious because paint is thin in the context of wet-sanding and there's no room for error.

Remember, wet-sanding removes paint and so does the compounding and polishing steps...

If we don't think the majority of people that take the how-to information posted to this forum by our members can take this information out into their garage and be successful putting the information into practice on their car in their garage, then at a minimum we need to step in and point out any potential problems that everyone needs to be aware of.

On that note, it's important to keep in mind that the MAJORITY of all wet-sanding is done on fresh paint in a body shop situation, not on thin, factory baked-on, hardened paint. You see, fresh paint sprayed at a body shop is sanded shortly after it has been sprayed, usually within days and while it's still soft enough to easily buff out your sanding marks.

Also, if a painter knows the car is going to be wet-sanded, they usually apply some extra paint so the person doing the wet-sanding and buffing has more film-build to work with. You don't have these important factors working in your favor when you work on factory baked-on paint.

We know that if you visit multiple detailing discussion forums you're bound to read about the topic of wet-sanding and we think this is where a lot of people get confused because they don't hear the other side of the equation. That is that most wet-sanding is done on fresh paint sprayed at body shops, not the factory baked on finish on new cars. There's a HUGE difference in how easy or difficult it is to remove sanding marks out of these two very different examples of car paint.

Just to note... it's easy to wet-sand paint, that means removing paint and in the process instilling sanding marks into the paint... anyone can do this.

The tricky part is removing the sanding marks... that's where it helps to have a company like Meguiar's with the experience and a long history of providing the products the re-finishing industry relies on to do this type of work and that's why you'll find our Professional Line of compounds, paint cleaners and cleaner/polishes are recommended for use with a rotary buffer when doing any kind of wet-sanding and not DA Polishers. We've been there.. and we've done that... and we know what it takes for you to be successful.

So when we post how-to information on this forum, or when we "allow" forum members to post their how-to information on this forum we do our best to insure that it's accurate and will work for the majority of enthusiasts that look to Meguiar's for accurate how-to information.

So if you're reading this and are interested in doing any kind of wet-sanding to the paint on your car, please read the above information we've provided in our replies to this thread and before bringing the sandpaper down onto your car's paint, first post a thread to this forum outlining your ideas for your project and let our forum community chime in with help and suggestions so you don't get yourself into a situation you can't get out of...

Okay?

[AeroCleanse]

Re: Wet sanding with Dual Action Polisher

You should post the link to the youtube video Meguiar's did, where you used the DA and it looked good until you moved around a little and the scratches were clearly there.

[TwinSport]

Re: Wet sanding with Dual Action Polisher

Thanks Mike!

I defenetly missed to warn everyone. I have nothing to add to Mike's reply.


@AeroCleanse: In my case, defently all scratches (sanding marks, I guess you mean them?) are gone. I checked it under different light and there wer just left the deep scratches created by the knife where I only rounded the edges so that the human eye can't see the scratch any more without looking closely at it.

[ZoranC]

Re: Wet sanding with Dual Action Polisher

No matter what people might say there is something about wet sanding using electrical tool that makes me extremely uncomfortable.

[seth1066]

Re: Wet sanding with Dual Action Polisher

My observation is that the paint on this plastic grill is perhaps a flex type of paint as used on bumpers. That paint is inherently a lot softer than is used on metal body panels. This soft paint could be the reason for the seemingly good results of the DA on sanding marks in this particular and very specific case. I would think that the rest of the car, with the much harder paint, would not come out anywhere near as well using the DA.

[yalerd]

Re: Wet sanding with Dual Action Polisher

Awesome thread!
Maybe this was successful because it was focus on a small paint section, the pad covers enough paint and you progress quickly. Maybe not the same results when done to an entire body panel, just a thought

Great replay Mike, lots of great points you made, thanks

[seth1066]

Re: Wet sanding with Dual Action Polisher

Awesome thread!
Maybe this was successful because it was focus on a small paint section, the pad covers enough paint and you progress quickly. Maybe not the same results when done to an entire body panel, just a thought

Great replay Mike, lots of great points you made, thanks

Not the same results, here's why: Grill paint = soft paint, Body panel paint = hard paint; imo.

[TwinSport]

Re: Wet sanding with Dual Action Polisher

Interesting point. Opel paints are soft anyway. But I dont think the grill is softer than the paint, at least it has less stone chips then the bonnet. Some one on a German forum also wetsanded his VW Golf and removed the marks with a DA polisher. As you know VW paints are pretty hard but still it worked. He used a small spotting pad and some CG polish. The results were amazing, nice glossy surface without a scratch. Before any one starts wet sanding he should defenetly get a piece of painted plate and try it our before attacking the paintwork on the car. Next month I will try to correct some stone chips and deep scratches on my father's car and I will post my results.

[seth1066]

Re: Wet sanding with Dual Action Polisher

Interesting point. Opel paints are soft anyway. But I dont think the grill is softer than the paint, at least it has less stone chips then the bonnet. Some one on a German forum also wetsanded his VW Golf and removed the marks with a DA polisher. As you know VW paints are pretty hard but still it worked. He used a small spotting pad and some CG polish. The results were amazing, nice glossy surface without a scratch. Before any one starts wet sanding he should defenetly get a piece of painted plate and try it our before attacking the paintwork on the car. Next month I will try to correct some stone chips and deep scratches on my father's car and I will post my results.

The paint used for plastic and flexible bumpers, in my direct experience, is different from that used on the metal body panels and is softer. The fact that the grill has less stone chips than the bonnet is indicative of softer paint.

When you say "a guy on another forum" had result X, it really isn't a conveyance of first hand knowledge. We have no idea whether or not the result is as claimed.

[seth1066]

Re: Wet sanding with Dual Action Polisher

No matter what people might say there is something about wet sanding using electrical tool that makes me extremely uncomfortable.

The thread title sounds like he used the DA as a sander, but I think he used the Meg's sanding block in the picture.

[Markus Kleis]

Re: Wet sanding with Dual Action Polisher

The paint used for plastic and flexible bumpers, in my direct experience, is different from that used on the metal body panels and is softer. The fact that the grill has less stone chips than the bonnet is indicative of softer paint.

When you say "a guy on another forum" had result X, it really isn't a conveyance of first hand knowledge. We have no idea whether or not the result is as claimed.

Well... maybe.

The paint PROCESS is different, and a flex agent is added on plastic sections (like the bumpers) so if it does take an impact the paint can "give" along with the plastic- a quality not needed on metal.

[seth1066]

Re: Wet sanding with Dual Action Polisher

Well... maybe.

The paint PROCESS is different, and a flex agent is added on plastic sections (like the bumpers) so if it does take an impact the paint can "give" along with the plastic- a quality not needed on metal.

How the paint becomes flexible isn't at issue; for paint to flex or "give" it has to be softer. If you take some 400 grit to your flexible bumper coating for a few minutes this will be readily apparent.

[Sydster]

Re: Wet sanding with Dual Action Polisher

The thread title sounds like he used the DA as a sander, but I think he used the Meg's sanding block in the picture.

That's how i got it too.