View Full Version : Variables That Impact Paint Polishing

Michael Stoops
Sep 13th, 2012, 12:25 PM
Variables. We all know they exist when it comes time to polish paint, but are you really thinking about all the things that impact your results? Sure, we talk about paint hardness all the time, but often just sort of glossing (no pun intended) over that and ignoring some of the other important variables that impact our results. Variables contribute to the overall result, they are things that change from project to project or can be changed during a project, and they impact every car, every time. If you have a single process for polishing paint then you're really missing the mark half the time. A really good detailer knows how to adjust their polishing process to that car, that customer, that environment, and that day.

In this discussion we hope to get you thinking about 10 important and interrelated variables that will impact your results, and determine your success when polishing paint. If you keep these in mind the next time you're struggling with a particular paint you'll be able to think through the problem, resolve the situation, and obtain the results you're looking for.

#1. Tool

Obviously tool choice is a major contributor to polishing results.
The tool determines which type of unwanted defects you might get. For example, a rotary buffer may create swirls, holograms, or "cut through" while an orbital polisher may create hazing, micro marring or "tick marks". Tool choice can also dictate how many buffing steps you need to do in order to obtain a swirl free result.

Other tool related impacts include:

Single speed or variable speed?

Can you adjust the speed of the tool to address a given situation?

Large and heavy or small and light?

Can you remain consistent if you're getting fatigued because of the tool?

Side handle or top handle, or no handle at all?

Ergonomics is important - are you comfortable holding the tool?

Quality of tool and its overall condition.

Is the tool running smoothly or are the bearings grinding and you're worried it will start shooting sparks out the side soon?

#2. Liquid Product

Are you using the right product for the job, tool, etc? Are you using the product correctly? Diminishing abrasives behave differently than SMAT abrasives do and require different techniques. For example, in final finishing if you're using a SMAT product like M205 you aren't working it to the point of abrasive break down because the abrasives don't break down - this means you can usually perform the task in less time than needed with a diminishing abrasive. And with a diminishing abrasive product you have to work the polishing area uniformly with the abrasives in all stages of diminishing function so as to achieve a uniform finish.


If you expect too much out of a product you may end being disappointed. We often hear people complain that a wax didn't remove all the swirls in their paint, but that's not what a wax is designed to do. Waxes may hide some issues, but unless it's an effective cleaner wax, it won't take out many defects.

You need to match the aggressiveness of the product to the level of defect and the hardness/softness of the paint. Reaching for the most aggressive product on the shelf every time can lead to the creation of a variety of defects just because it's too aggressive. But reaching for too mild a product yields the opposite effect. Product selection needs to be balanced to the task, the paint, the tool, etc and it's not necessarily the same product every time.

#3. Supplemental Wetting Agents

Supplemental wetting agents are just as the name implies - an additional source of lubrication beyond that offered by the compound, paint cleaner or polish being used. Usually these are in the form of detail sprays or just plain water, and there only a couple of reasons why you should be using them:

The product manufacturer recommends it. Some companies, Farecla for example, actually call for the use of water as a wetting agent when using some of their products, and in some of those cases the amount of water used is surprising if you're not used to working this way. These products were designed to be used this way, and maximum results can not be achieved without using water as a supplemental wetting agent.
The user is not gettng the intended or expected application experience and wants to adjust the surface lubricity or buffing cycle. This happens most commonly when the product is drying out and creating high levels of dust.

Just as some liquid products are designed specifically to be used with a supplemental wetting agent, others will actually suffer when used this way. There are times, as mentioned above, when a small amount of a wetting agent can extend the buffing cycle, but be sure your reason for choosing to do so is valid. If the product is dusting due to ambient conditions of high heat and/or low humidity, a small amount of a supplemental wetting agent may be beneficial. Of course, if the reason for the dust is over use of product, not keeping the pad clean, or some other reason that can otherwise be corrected, then use of a supplemental wetting agent may only exacerbate the problem as it won't address the root cause of the dusting. You may actually get the opposite effect you were hoping for, and that's rarely a good thing.

What you use as a supplemental wetting agent can have an impact on the buffing process as well. You may think that since a quick detailer works great as a lubricant while claying a car it should do the same when buffing. But silicones and polymers in some spray detailer formulas can actually retard defect removal while buffing with compounds. In some cases they can actually cause the pad to load up faster and make it less effective, too.


#4. The Buffing Pad

There are almost as many choices when it comes to pad selection as there is choice in tools and liquids. Since the pad is what makes the most contact with the paint when buffing, it should be very obvious that this is a huge variable. The pad contributes to the cutting, polishing or finishing just as much as the liquid product does.

Some things to consider when selecting and using pads:

Are you using a pad that is appropriate to the liquid being used? You shouldn't use a cutting pad with a finishing polish - that product should be used with a finishing pad or maybe a polishing pad, depending on what you're trying to accomplish. Conversely, you shouldn't use a compound with a finishing pad - that product should be used with a polishing pad or cutting pad, again depending on what you're trying to accomplish. There is some leeway here, but you have to work within the limits of the pad and product.
Is the pad appropriate to the tool being used? Wool pads are for rotary use only. Microfiber pads are for DA use only. Foam pads can be used with either tool
Is the pad properly matched to the process? If you're trying to remove sanding marks, even if you select the correct compound, you won't get very far if you're using a soft finishing pad. And if you're trying to achieve maximum gloss and clarity with a finishing polish but you still have that cutting pad on your buffer, well, good luck with that.
Is the pad of appropriate diameter for the tool, process, and user skill? Remember, the larger the diameter of the pad the more aggressive it is on a rotary buffer, but the less aggressive it is on a DA. An 8" pad on a DA may cause the tool to bog down earlier, will lessen the cutting ability dramatically, and can be unwieldy to use.
Is the pad being used as part of a system? For example, our DA Microfiber Correction, comprised of two microfiber pads and two liquids, is the most highly engineered system Meguiar's has ever developed. While it is possible to use other liquids with these pads, the results and user experience may not be what you expected if you step outside the system. Consistent, repeatable results will happen when you stay within this system, using the liquids and pads as they were developed to be used together.

#5. The Backing Plate

This one is a kind of a "sleeper" since many people completely overlook the importance of backing plates. Many a swirl mark has been blamed on the liquid or the pad, when it could very well have been the fault of the backing plate. How's that possible, since the backing plate doesn't actually come in contact with the paint? Well, the backing plate determines if the buffing pad is supported in the right places, and it dictates the "footprint" of the pad on the paint. The backing plate is what directly translates your pressure, no matter how great or small, directly to the pad. If there's a mismatch, that can show through in the final finish.


In our article Backing Plates - More Than Just A Way To Stick A Pad To A Buffer (http://www.meguiarsonline.com/forums/showthread.php?52853-Backing-Plates-More-Than-Just-A-Way-To-Stick-A-Pad-To-A-Buffer) we go pretty in depth into why selecting the right backing plate is critical to the paint polishing process, and what can go wrong when the pad and backing plate aren't synchronized. Significant considerations when making you backing plate selection include:

Matching the backing plate to the pad used
Using the right backing plate for the tool chosen

Proper diameter?
Proper weight?

If using a hook & loop attachment system (ie, Velcro) is the "hook" synchronized to the "loop"? If not....

Engagement could wear our prematurely
Rotary use could see the pad detach, causing paint damage
Orbital use could generate unnecessary, and unwanted, heat

Following a system approach with pads and backing plates will ensure the best possible polishing results. If the manufacturer of the pad you're using recommends a specific backing plate for that pad, use it!

#6. Paint & Body

This is almost two separate variables, but they really go hand in hand so we're keeping them together.

Two aspects of the paint itself set the tone for the entire polish job -

Paint Defects

Severe defects like sanding marks, heavy scratches, and heavy car wash marks will invite certain polishing procedures. This usually includes more aggressive liquids and/or pads, and possibly choosing a rotary buffer rather than a dual action polisher. It could mean longer buffing times, repeated passes, or multiple steps to achieve the final finish you're looking for.
Light defects like hairline scratches and light oxidation usually require a different procedure. This may be a one step with a good cleaner wax, or it might be just a finishing polish on a soft pad before applying wax. There's no need to get overly aggressive for light defects, so go easy if this is what you're up against.
Since the severity of defects can vary widely from car to car, you need to be able to comfortably and effectively use both procedures, or a combination of them, depending on the situation your facing.

Paint Hardness

Varying degrees of "hardness" will determine the process required to correct defects.
Simple "hard" and "soft" are minimalistic descriptions of paint types - it's often more complex than that.

"Soft" alone can be very easy to correct with a minimum of work
"Soft and delicate" can be extremely frustrating because, while you can quickly remove the original defects, it seems everything you do creates a new set of problems
"Hard" sometimes just needs multiple aggressive passes to correct defects
"Hard and delicate" can be resistant to correction but still create a bit of haze during the most aggressive process and a less aggressive finishing process must be done to obtain a flawless finish

Fortunately, most paint falls into the high point of a "paint hardness bell curve" and can be corrected without major adjustments to your process. Fine tuning of that process may be needed, but wholesale changes to it usually aren't for most paint.


We often see people asking questions on forums along the lines of "how hard is the paint on this make and model?", but that's not a sure fire way to know what the paint on the car in front of you is like. Most manufacturers make changes to the paint formulations they use, sometimes in the middle of a model year. They don't use the same paint in every factory, or on every model. Sometimes there even issues in the painting process that produce a finish that may appear visually the same as every other car built that year, but once you start buffing on the car in front of you, you get a different reaction from the paint. A little anecdotal evidence is fine but don't let yourself get too caught up in this. The only thing that will tell you how hard or soft, how delicate or not the paint is on the car in front of you is a test spot.

The other half of the Paint & Body Variable is the way in which the body panel itself can impact things. The material used in the body panel (ie, the substrate) will impact the buffing cycle due to heat transfer and dissipation. For example:

Steel panels will hold heat longer
Aluminum will tend to heat up faster but cool more quickly, and it can also buckle when heated too much
Plastic will get hot spots
Fiber Glass can generate static electricity

When you consider that many cars are using multiple materials in the body, you start to realize that the buffing cycle on each panel of the same car can vary. As an example, the Mazda MX-5 Miata uses steel for the front fenders, doors and rear quarter panels, aluminum for the hood and trunk lid, and a type of plastic for the front and rear bumper covers. If you're doing an aggressive rotary correction on a car like this you may find the paint responding differently on these surfaces due to the heat being generated by the buffing process. The liquid you're using may behave differently as well, again due to the heat. Even when using a dual action polisher in an aggressive manner on a bumper cover can cause issues - a hot spot here can cause the paint to literally twist off the panel. Yes, even when using a dual action polisher, and even though you just did the exact same process on an adjacent steel panel. Heat dissipation was better on the steel panel, but the bumper cover developed a hot spot under the same circumstances, with disastrous results.

And just as the substrate of the panel can impact your results, so too can the shape of the panel. Buffing in the middle of a big, flat hood or door is pretty straightforward. But what about complex curves, sharp body lines, or just really tight spaces that you can't reach with a buffer? Burning an edge becomes a very real possibility, or you may be forced to do some work by hand. Or you may have to put down the rotary and pick up the dual action tool, or vice versa. Or you may need a smaller pad to reach an area. And we've already discussed how tool selection, pad size, etc can impact your results. You need to keep all that in mind if you have to change things up because of the shape of a body panel.


#7. User Technique

All the things the user does effects the polishing outcome, often in dramatic ways. We even have an entire article (http://www.meguiarsonline.com/forums/showthread.php?53631-Rotary-Buffing-Techniques-How-Variables-Impact-Results) dedicated to just this one variable. While that article concentrates mainly on rotary buffing techniques, much of it holds true for dual action polishing variables as well. Chief among these differences in techniques include:

Machine speed setting
"Arm speed" across the paint
Downward pressure
Keeping the pad flat against the surface
Working a proper size area
50% overlap on passes

#8. Environment

Do you think climate will effect the polishing result on this car?

OK, that may be an extreme case, but we see extremes all the time when dealing with people using the same product in different parts of the world. Temperature and humidity can dramatically effect the buffing cycle, which in turn impacts defect removal and finish results. For example, someone using a product in Phoenix, AZ in the peak of summer and is experiencing temperatures well over 100F and humidity in single digits will often find products drying out very quickly on the paint surface. Dust becomes an issue, and product removal can be a challenge. You can imagine how frustrating this can be, and the marring that can be created by either dry buffing, or just struggling to remove the dried product. But the exact same product used on the same day in Detroit, MI may be an absolute joy to use. With temperatures in the mid 70F range and humidity relatively high, the user here enjoys a long buffing cycle, virtually no dust, and easy wipe off of the light residue.

But you don't even need to experience extremes as described above. Just using the same product during different seasons in the same geographic location can yield the same dramatic differences. Here in SoCal at Meguiar's HQ we'll see Phoenix like weather in the summer and lower temps with higher humidity in the middle of winter. That alone, even in the same garage, can impact the product, and the results. This often requires the user to slightly tweak their technique to optimize results.

Beyond the simple temperature and humidity changes, other environmental impacts include:

Wind and particulates in the air
Indoor lighting (ever use a large pair of halogens that generate a lot of heat?)
Direct sunlight (some mobile detailers don't always have the luxury of all the shade they want)
Activity in surrounding areas (heavy traffic creating fallout, trees depositing a fine sap mist, nearby road construction, etc)

#9. Time & Expectations

We've all been there - you think the car isn't too bad so it's just going to take a couple of hours to accomplish what you want, but then the paint refuses to cooperate. Now what? You have limited time to improve the finish, so what do you do now. What compromise do you make to adapt to this situation?

If you're detailing for dollars, and you have a customer with extremely high expectations but is only willing to pay a minimal amount, how do you come close to his expectations without short changing yourself? Otherwise, do you really understand just what the customer is looking for? What's important is what the customer wants, not how you want the paint to be. Always striving for perfection is admirable, and you can argue that we should always strive to achieve the very best we possibly can, but if the customer is happy with a good all in one and that's all they want to pay for, that should be good enough for you, too. What can set you apart here, however, is your ability to maximize results with a good one step. Product and pad selection, technique with those choices, understanding how the paint is responding, and all the other variables previously mentioned will determine if can reasonably achieve or exceed the customer's expectations.

Why are you detailing this car in the first place? Detailing can fall into three basic categories:

Restoration - this can take a huge amount of time, may mean very thin paint in rough shape, and the expectation may be to maintain the original appearance and accept some of the patina and age that can't be corrected without a repaint.
Preventive Maintenance - this should be pretty straightforward and not an all day job. A car in good shape to begin with doesn't need aggressive work to make it look darn near perfect. Choosing the right product/process here is a major time saver.
Exhibition Detailing - if you're prepping a car for a major concours event like Pebble Beach, Amelia Island or any of the ever growing number of meticulously judged shows, you're going to do things to maximize the gloss and depth that you wouldn't normally do on a daily driver. And it's going to take a long, long time to achieve this extreme level, not to mention a very high level of skill with a variety of tools to get there.

#10. Passion!

Anyone can see the difference in results from someone who "wants" to do the work versus someone who "has" to do the work. Attitude is everything. As with any other endeavor......

A positive attitude
Genuine interest in the project
Do you really give a darn?
Having high standards

....really impact polishing results. Paint polishing can be very hard work, but if you're not having fun with it your results are going to suffer.

So now what?

Now that you know the 10 Polishing Variables that impact results:

When things go well and the paint comes out beautiful, you know that it was because choices you made in the 10 variables were aligned with efficiency and excellence
When things are not going well, and you are struggling to get your intended or expected result, you can use your knowledge of the 10 variables to "find and fix" for better results

Using this new found knowledge means isolating a variable to see if changing it up resolves your problem. This might happen if you're trying a new product, whether that is a different tool type, a new polish (maybe a SMAT versus diminishing abrasive polish), a new pad, etc. You may want to isolate a variable if you're trying a new process or technique, too. It is important that you properly isolate a variable if you're going to gain anything from the experience. This is easily done with the following things kept in mind:

Do side by side applications of your testing
Keep 9 of the 10 variables the same on both sides - you're trying to determine if that one variable is the issue, so changing more than one at a time clouds the test
Change only that one variable, the one you suspect is causing the problem, on just one side: this could be the new product you're using, the new technique, whatever.
Obviously the paint itself is what's giving you fits you can't change the paint from one side to the other, so you'll have to evaluate your initial results and test a different variable on the other side. But again, change just one variable - liquid, pad, speed, etc - or you risk throwing off your results.
Critically compare your results under good lighting, and strive to understand the differences you're seeing. If the first variable that you changed didn't change the results, think through the other potential variables and select the one you think is most logically responsible for the problem you're facing.

This article (http://www.meguiarsonline.com/forums/showthread.php?54103-Dealing-with-crazy-hard-paint-or-Don-t-believe-everything-you-read-on-the-Interwebs!)discusses some of the thought process involved when a paint system proved to very different than what we expected, the steps we took to determine the right process, and the end result after experimenting with some of these variables. It was very frustrating at first, but a positive attitude and perseverance got us through it and the end result speaks for itself.

This hobby as often been referred to as the art of paint polishing, but it's really equal parts art and science. And the best detailers know how to adjust their polishing process to that car, that customer, that environment, and that day.

Sep 13th, 2012, 04:52 PM
Excellent write up Michael! Sure to help many struggling with detailing endeavours.

Sep 13th, 2012, 05:05 PM
Does it help? Or list the ways you're in trouble... ;)

Sep 13th, 2012, 05:45 PM
I really like the picture for the #8 Environment. LOL

Sep 13th, 2012, 07:19 PM
Great write up Mr. Stoops. I think your post should be required reading. I have been reading so many posts of late how someone has used a tool, product or pad and are not happy with the way things turn out.

I do have one thought that might go along with #2. So many people jump in trying their hand at paint correction and do not achieve their expectation. I feel that the reason for this is that the people do not fully consider the value of the test area ( that 2x2 ) area that is used to see if their process is going to give them what they want be fore they do their whole car.

Sorry for my rant.

Sep 14th, 2012, 01:14 AM
Thanks Michael. A very exhaustive article. The photo in "8" really exhausts me. :)

I think you wiil understand when I say these sentences have different meanings:
Mr. Stoops, improving user experience.
Mr. Stoops, improving user experience.

Sep 14th, 2012, 04:15 AM
Simply an OUTSTANDING article!

I have to agree with some of the above, picture at #8, well that, ahh, hmmm, kinda, BITES! I hate to think what will be here in a couple 'o months...LOL.

Great thinking and writing Michael.


Michael Stoops
Sep 14th, 2012, 07:10 AM
Thanks guys! That ice shot for #8 has been floating around the Internet for years and it's a great shot, no doubt about it. Just FYI, the three classic cars in #6 were shot at RM Auctions in Monterey in 2011, and every time I see beautiful machinery like that, even while composing the image and looking for the right angle to shoot, I can't help but think what it would be like to polish the paint on those shapes!

Does it help? Or list the ways you're in trouble... ;)LOL!! It should be doing both, hopefully. Let's face it, how do you get yourself out of trouble if you don't understand the trouble you're in in the first place?

David, have you given any consideration to coming out here next weekend for the NXT Institute super advanced class we're hosting with Kevin Brown and Jason Rose? Announcing NXT iNtense eXtreme Training 9-22 & 23-2012 (http://www.meguiarsonline.com/forums/showthread.php?55694-Announcing-NXT-iNtense-eXtreme-Training-9-22-amp-23-2012&highlight=nxt+institute)

Oh, and I would be terribly remiss if I neglected to give credit to Jason Rose for his invaluable input in the creation of this article. I could sit and pick his brain all day long, for many days in a row, if we both had the time.

Detailing by M
Sep 14th, 2012, 08:16 AM
nice article. that really puts all things in perspective.

Sep 17th, 2012, 03:26 AM
David, have you given any consideration to coming out here next weekend for the NXT Institute super advanced class we're hosting with Kevin Brown and Jason Rose? Announcing NXT iNtense eXtreme Training 9-22 & 23-2012 (http://www.meguiarsonline.com/forums/showthread.php?55694-Announcing-NXT-iNtense-eXtreme-Training-9-22-amp-23-2012&highlight=nxt+institute)

Yes, much consideration. However, prior commitments prevented my attending. I'm hoping there will be many photographs, perhaps videos, of NXT. I particularly look forward to any question and answers during the visit from the chemist.

I'm sure the event would improve my user experience, in all sense of the words. Although as ventriloquist Jeff Dunham's puppet, Peanuts, often does with his hand passing over his head while saying, "ewow". Most of the discussion will be over my head....!

Jan 5th, 2013, 07:44 PM
Excellent write up Michael! Sure to help many struggling with detailing endeavourshttp://www.dvxs.info/a11.jpghttp://www.dvxs.info/k2.jpg

Jan 5th, 2013, 08:04 PM
Incredibly well written article Mike that really puts everything into perspective and is easy to follow.