Can an air-powered DA Sander be used to polish paint?

[Mike Phillips]

Can an air-powered DA Sander be used to polish paint?

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Recently a new member asked the above question and because the question comes up often enough on this forum, the question and and answer qualify to have their own dedicated thread here in our "Hot Topics and Frequently Asked Questions" forum group.

Note, this wasn't an in-depth study, just some quick side-by-side testing I did on-the-fly on a Saturday afternoon after finishing some other projects like the Flits metal polishing project using the brass boat propeller seen below.




On to the testing...

First, the air-compressor I'm using is a large Ingersoll Rand unit and it's able to easily maintain 100 psi air flow to the sander.

Ingersoll Rand Air Compressor




This shot taken immediately after running the sander...



From left to right...

3M 3/16 12,000 RPM RO Sander with 5" Backing Plate with 5.5 Surbuf MicroFinger Buffing Pad
3M 3/16 12,000 RPM RO Sander with 6" Backing Plate with 6.5" CCS Orange Light Cutting Pad
Dynabrade 3/16 10,000 RPM RO Sander with 6" Backing Plate with 6.5 Surbuf MicroFinger Buffing Pad



Between the 3M unit and the Dynabrade Unit, the 3M DA Sanger had more power or a better way of describing it would be to say that it was better able to keep a pad rotating under pressure.

This is key for the correction step because it's when the pad is rotating that paint is being removed and thus defects are being removed.


The two 3M DA Sanders are identical and we will be stocking these units.


6.6" Pad Test
I tested 6.5" foam pads and 6.5" Surbuf MicroFinger Pads using 6" backing plates.

With the air throttle wide open and with firm to extreme downward pressure I could not stop the Surbuf pad from rotating when the pad was held flat and when the pad was held on edge.

With the air throttle wide open and with firm to extreme downward pressure I was able to stop the foam pad from rotating both when the pad was held flat and on edge.

5.5" Pad Test
With the air throttle wide open and with firm to extreme downward pressure I could not stop the Surbuf pad from rotating when the pad was held flat and when the pad was held on edge.

With the air throttle wide open and with firm to extreme downward pressure it was very difficult to stop the foam pad from rotating both when the pad was held flat and on edge.


Summary
If you want to use a air-powered DA Sanger to remove swirls and scratches then stick with the 5.5" pads either foam or Surbuf Microfiber pads and you should be able to tackle most of what comes you're way.

The 6.5" Surbuf MicroFinger pads worked on both the 3M DA Sander and the Dynabrade DA Sander but the 3M unit did do a better job of keeping the pads rotating.

You can use 6.5" foam pads with the air-powered DA sanders but to keep the pad rotating you can't push as hard and you really have to focus on keeping the pads held flat to the surface.


My comments...
I was really impressed with the rotating ability of the Surbuf Microfiber pads when used on both of these air powered DA Sanders. To date, I've found the Surbuf Microfiber pads are best suited for correction work, that is removing defects as they can leave behind tick marks, or micro-marring like foam cutting pads can leave behind on some paints. So plan on following any correction steps with MicroFinger buffing pads with another polishing step using either a foam polishing or foam finishing pad and a light cutting polish.



Product showcased
3M Air Powered DA Sander - Coming soon...
Surbuf R Series 4 Inch Buffing Pads 2 Pack
Surbuf R Series 5.5 Inch Buffing Pads 2 Pack
Surbuf R Series 6.5 Inch Buffing Pads 2 Pack
6.5" CCS Foam Pads
5.5" CCS Foam Pads
5.5" Flat Foam pads
6.5 Flat Foam Pads
5.5" Hydro-Tech Pads
6.5" Hydro-Tech Pads


See also...

Surbuf MicroFinger Buffing Pads now at Autogeek!
List of Sanding Discs at Autogeek.net

[A4 1.8tqm]

"With the air throttle wide open", so the machines were spinning the pads at 10,000-12,000 rpm? Or did you dial down the air flow? It seems it would be difficult to know exactly how fast the pad is rotating. The only Pneumatic sander I've used did not rotate, so I'm interested in the 3M unit. Any idea on the price once they are on the shelves?

[C. Charles Hahn]

So how does the corrective ability of the pneumatic tools compare to the corrective ability of electric DAs?

Any idea on the price once they are on the shelves?

Other vendors I've seen are selling 3M DAs for ~$150-180....

[Mike Phillips]

"With the air throttle wide open", so the machines were spinning the pads at 10,000-12,000 rpm? Or did you dial down the air flow? It seems it would be difficult to know exactly how fast the pad is rotating. The only Pneumatic sander I've used did not rotate, so I'm interested in the 3M unit. Any idea on the price once they are on the shelves?

My guess is the RPM's are rated at no load?

I don't know, I'm not a 3M Engineer. Here's what I know,

Just like an Electric Polisher, you don't turn the tool on until the face of the pad is against the panel.

Make sense?

You know what happens if you turn a polisher to the "On" position with product on the face of the pad while the pad is in the air?




Point being, when you place the face of the pad against the paint AND then turn it on, the pad is rotating similar to an electric polisher like the PC, Megs or GG.

Also, when I did this testing it was to see check for correction ability, that's what most people want to do when they're using a machine to buff their car's paint.

In order to correct defects "in" the paint, the pad needs to rotate and that's the make or break feature of a DA style tool.


Anyone coming to the class next weekend will have a chance to test any and all of this out...

Detailing Class at Autogeek in Stuart, Florida on Saturday, April 24th from 8:00am to 3:00pm







See you here!

[A4 1.8tqm]

So your saying that you felt comfortable using the tool at it's maximum operating speed, what ever that may have been under load?

I was under the impression that the 10,000 rpm Pneumatic DA Sanders operate too fast to safely use with foam pads and polish. I don't remember where I got that idea. Thanks for posting your "on the fly" tests Mike, always a great read!

See you here!

I wish!

Other vendors I've seen are selling 3M DAs for ~$150-180....

Thanks Shiny, sounds reasonable enough.

[Mike Phillips]

So your saying that you felt comfortable using the tool at it's maximum operating speed, what ever that may have been under load?

No, not at all.

What I was trying to say is forget the stated RPM's because the only thing that matters is when you turn the tool on and start to buff with it and it worked pretty much like an electric polisher. That means COMPLETELY controllable.

Let me see if I can say it a different way, under load, and that's how you would use it, the pad is rotating like it would on the 5 to 6 setting on a PC, Megs or Griot's electric DA.

It might spin up to 10,000 RPM if you hold it in the air but I never do so it doesn't matter, the only thing that matters is what the pad does when it's against the paint and when it's against the paint it rotates a lot slower than 10,000 RPM

I don't know or even care about the specific numerical RPM or OPM of how fast the pad is rotating under load because I never focus on that kind of detail, what I focus on is,

A) Is the pad rotating?
B) Am I reaching my goal?

That's the two things that matter when I'm trying to remove defects out of paint. Numbers on a chart are great, but they don't mean anything when I"m standing next to a car for hours buffing out the paint. All that matters is the action taking place.

I see people get all hung-up on the OPM rating of the 3 popular electric DA Polishers and I've never figured out why?

If you're trying to remove swirls, scratches and water spots you're going to be on the high setting no matter what OPM number is written on a piece of paper or on the side of a box, that is you're going to be on the 5.0 to 6.0 setting.

When you go to polish, you're going to be on the 4.0 to 5.0 speed setting and when you go to apply a wax you're going to be on the 3.0 to 5.0 setting depending upon what you're trying to do.

The stated OPM of any of the 3 electric polishers commonly talked about on forums doesn't matter a hill of beans from a practical point of view. Select your speed setting, turn the machine on and get to work.

Same kind of thing with these air powered DA Polishers. You don't have to open the throttle up wide open but if you don't under load the pad is not going to rotate. I don't need a number written on a piece of paper or on a webpage or on the handle or even the side of the box about the specifications of the air-powered DA sander, what I need is to place the foam pad against the paint, turn the tool on and then throttle up till I see the pad rotating and then get to work.

After I remove all the swirls and scratches if I'm going to use an air-powered DA Sander to also do the finish polish work, then I'll probably turn the throttle down a little. I still don't need to know what the RPM's are, I look at the black mark on my backing plate and watch to see if the pad is rotating and a little quicker pace than when I was doing the heavy correction step as at some point I'm using less downward pressure.

Does that make sense?

I know it would be more fun for you to go out into the garage and actually play with these tools on Harvey as that's what's parked in the Studio right now and then you would see what I mean.

[A4 1.8tqm]

Let me see if I can say it a different way, under load, and that's how you would use it, the pad is rotating like it would on the 5 to 6 setting on a PC, Megs or Griot's electric DA.

It might spin up to 10,000 RPM if you hold it in the air but I never do so it doesn't matter, the only thing that matters is what the pad does when it's against the paint and when it's against the paint it rotates a lot slower than 10,000 RPM

Just what I wanted to know. The tool is not operating at 10,000 rpm under load. But that is pretty much what I said:

...you felt comfortable using the tool at it's maximum operating speed, what ever that may have been under load?

For some reason I thought the sanders labeled 10,000 rpm weren't OK to use for finishing a painted surface, like they were only meant for "removal" sanding in prep for painting etc.

Thanks again Mike.

[dawnn]

I don't know right now how fast my da will spin, I is a very old one, I will have to wait till I get some pads and the backeing plate, but it does have an adjustment on it, how fast should it spin and how will I know if it going at the correct speed??
If I had ever used a pc before I would at least have an idea... so how will I know?
Another question I have is does the product sling out all over the place with a da or pc like it does with a rotary??

[C. Charles Hahn]

If I had ever used a pc before I would at least have an idea... so how will I know?

Generally speaking, due to the nature of DA polishers, the best and only way to get optimum correction ability is to run the machine at its maximum speed.

There may be cases where the machine needs to be slowed down (either via a dial on an electric tool or by using an air regulator on a pneumatic) to control compounds or polishes dusting, or for final polishing, but for the most part during any corrective procedure you'll want to run flat out. Since the motion of the tool is "orbital" you won't likely cause damage to the paint as long as you use common sense and are following best common practices.

It might also help you to watch some of the many YouTube videos out there demonstrating the use of a PC or other DA polisher, as usually when you watch the motion of the backing plate and pad closely you can tell when the pad is "rotating" and when it is simply jiggling against the surface, not providing much in the way of substantive results. You can use that as a guide to judge what you're seeing with the motion of your own tool as you use it.

Another question I have is does the product sling out all over the place with a da or pc like it does with a rotary??

The short answer to that one is, if you're doing it right product should never "sling out all over the place" even with a rotary polisher.

The long answer is that no, generally speaking the action of a DA polisher is nowhere near as powerful as a rotary polisher, making it far less likely that you're going to be slinging product AND making it much easier to develop your technique. I always tell people that starting out with a rotary is entirely feasible, but the learning curve is MUCH steeper going that route.

If you start learning with a DA, on the other hand, you're working with a machine that is exponentially easier to control and safer to use from a beginner's perspective. I would have no qualms about even handing a responsible young kid (6-8 years old) a DA to practice with, but I would NEVER hand them a rotary to use -- even adults sometimes have a hard time controlling a rotary despite having a lot more physical strength to work with.

With all that said, however, I do have to concede that learning with a DA can be a double-edged sword. Utilized properly, they are an excellent tool for developing a buffing technique that can be translated into the use of other types of polishers fairly easily and successfully. If abused, though, it is easy to get into bad habits that when translated to using a rotary, forced rotation DA, or other tools can make them ineffective, if not downright dangerous.

I would definitely suggest you read up as much as you can about the proper technique for using a DA polisher (electric, pneumatic, or otherwise the approach is pretty much the same -- the main factors to consider are the type of pad and product you're using: foam or surbuf, DAT or SMAT, et al.) to avoid getting into any bad habits early on.

[deuce01]

Picking up on an old thread, has anyone tried this pneumatic DA polisher?

6" Dual Action Air Sander

I realize it's probably not equal to the 3M unit for sale here but I'll probably only use it once or twice a year on my van and car. The paint on my new to me used car has many scratches and swirls (it's black) so I need to clean it up and then will maintain it properly from there.

Thanks!