Show Car Garage Video: How-To do a "Section Pass" when Machine Polishing with a DA Polisher

Show Car Garage Video: How-To do a "Section Pass" when Machine Polishing with a DA Polisher


Here's how to do a "Section Pass" when trying to remove swirls, scratches and other below surface paint defects.

How to do a Section Pass

https://www.youtube.com/watch?v=Q70g83mnTn4




When talking about machine polishing on discussion forums or even in detailing classes, the below questions always comes up,

• What's a pass?
• How many passes do I make?
• What's a section pass?

The definition of a pass
There are two definitions of the word pass as it relates to machine polishing with any type of machine.


Single Pass
A single pass is just that. It's when you move the polisher from one side of the section you're buffing to the other side of the section you're buffing. That's a single pass.


Section Pass
A section pass is when you move the polisher back and forth, or front to back with enough single overlapping passes to cover the entire section one time. That's a section pass.

In most cases if you're removing any substantial below surface defects you're going to make 6-8 section passes to the section you’re working before you either feel comfortable you've removed the defects or you're at the end of the buffing cycle for the product you're using.


Buffing Cycle
The buffing cycle is the amount of time you are able to work the product before the abrasives have broken down, (if you’re using a product that uses diminishing abrasives), and/or the product begins to dry and you lose the lubricating features of the product. Different products have different buffing cycles depending upon the type of abrasives used in the formula and the different ingredients used to suspend the abrasives and provide lubrication.


Factors that affect the buffing cycle include,

• Ambient temperature
• Surface temperature
• Size of work area
• Type of machine
• Type of pad material
• Humidity
• Wind or air flow surrounding the car
• Amount of product used
• Technique

Wet buffing technique
Most compounds and polishes should be used so that there is enough product on the surface to maintain a wet film while the product is being worked. The wetness of the product is lubricating the paint as the abrasives abrade the paint and cushion or buffer the abrading action so the abrasives don’t simply scour the finish leaving behind swirls and scratches.


Dry Buffing Technique - Buffing to a dry buff
There are some products on the market where the manufacture recommends buffing the product until it dries. As the product dries you’ll tend to see some dusting as the product residue becomes a powder and the paint will have a hard, dry shine to it.

Although some manufactures recommend this, it’s important to understand what’s taking place at the surface level as you buff to a dry buff. As the product dries, in essence you are losing the lubricating features of the product and as this happens friction and heat will increase. As friction and heat increases, so does the risk of micro-marring the paint or instilling swirls either by the product residue or the pad material and/or a combination of both.

While we trust that the manufacture knows their products best, when we take a close look at what it means to buff on a delicate surface like an automotive clear coat, it doesn’t make sense to run a buffing pad on top of the paint without some kind of wet film to lubricate the paint at the same time. We always recommend that you follow the manufacturer's recommendations and use your own judgment.

Everyone new to buffing wants to be told some easily identifiable sign that they can use to tell when it's time to stop buffing and it's not that simple, so here's an indicator I've always used and taught to others,

Wet film behind your path-of-travel
As you're making a single pass with the polisher, the paint behind the path of travel of the buffer should have a visible wet film on it. If the paint behind the pad is dry and shiny, you've run out of lubrication and you're dry buffing. Turn the polisher off. Wipe the residue off and inspect using a Swirl Finder Light to make sure you didn't dull or mar the paint, you usually won't cause any harm, but pay attention when your running the polisher and don't buff to a dry buff. If you do, you can quickly re-polish that section by cleaning your pad and adding a little fresh product and making a few new section passes.


UMR
Remember, in most cases the goal is UMR or Uniform Material Removal. The reason for this is so that you remove an equal amount of paint over each section and in turn over the entire car. In order to do this you need a method that you can control and duplicate and for most people following a back and forth, side-to-side pattern works because it’s easy to remember, easy to do and easy to duplicate.


Resources
The above video segment is a 4 minute clip filmed during the extended version of How To Remove Swirls using any Dual Action Polisher like the Meguair's G110v2 and the Griot's Garage ROP and all models of he Porter Cable Dual Action Polisher, including the PC7424XP, PC7424, PC7336, G100


How to Remove Swirls using the Porter Cable 7424XP or any D.A. Polisher


http://www.autogeekonline.net/forum/...lies/smile.gif

***Update***

YouTube Video Interface added


:)

Great video and article Mike.

Thanks for posting

Quote:

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Originally Posted by Matt

Great video and article Mike.

Thanks for posting

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Thank you.

It's a rather simple idea but after years of talking and typing to fellow enthusiasts about machine buffing cars it became apparent that there needed to be some definition of what single pass and what a section pass meant...

That way everyone is on the same page...

Buffing out an entire car is simple a matter of buffing out the car section by section, no matter which type of tool you're using because you certainly don't buff out the entire car at one time.


:)

Quote:

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Originally Posted by Mike.Phillips@Autogeek

Thank you.

It's a rather simple idea but after years of talking and typing to fellow enthusiasts about machine buffing cars it became apparent that there needed to be some definition of what single pass and what a section pass meant...

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Agreed! I never realized how many single passes you needed for a section pass.

I'm only relatively new to machine polishing but it made me realize how much a polish needs to be worked before its finished. I guess that would be different with a non- diminishing abrasive product like 205 but with a product using diminishing abrasives, a section pass is far longer than I originally thought.

Glad I read this! Thanks for the video

Sent from my KFTT using Tapatalk HD

Quote:

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Originally Posted by Matt

Agreed! I never realized how many single passes you needed for a section pass.

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And just to point out to all you guys that detail cars for money...

If you're trying to get paid a fair wage for your work one of the things you need to do is educate your customer on how long it takes to properly and correctly buff out a single section of paint.

You must help them to understand that you cannot simply move the polisher faster to get the job done faster.

The pad needs to work the compound or polish against the paint for a certain amount of time in order to remove enough paint to remove the defects while also leaving the surface beautiful. And isn't that the point of buffing out a car? Make it look beautiful?


Hack detailers buff fast and leave a hacked up looking finish. The reason you CHARGER MORE for your work than hack detailers is because you do the job right and that means it takes not MORE time but the RIGHT AMOUNT of time.

Then either charge by the hour or charge by the job.

The first step also takes the longer because it's this first step that you remove enough paint to remove enough of the defects to get to an acceptable looking finish.

In a multi-part detailing project that includes compounding, polishing and waxing, it's the compounding step that takes the longest and if you don't remove the defects (that you want to remove) in the compounding step then they will be there when you wipe off the wax. That's a fact.

:)

Also for anyone that finds this thread be sure to click the link below and read this article and watch the video...


Video: Mark your backing plate to make it easy to see pad rotation




Polishing paint is a craft and an art form because besides using the right tools, pads, products and techniques, (that's the craft part), we each bring the human elements of care and passion to each project we take on and that's when polishing paint becomes an art form.


:xyxthumbs:

I saw the video this morning and gave it a shot !

My truck is black and the end result was great !

I learn something new and how to apply proper techniques. I will be detailing my truck in a few weeks and can't wait To see the end results.


Thanks Mike

Quote:

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Originally Posted by hdcustom00

I saw the video this morning and gave it a shot !

My truck is black and the end result was great !

I learn something new and how to apply proper techniques. I will be detailing my truck in a few weeks and can't wait To see the end results.

Thanks Mike

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Good to hear and welcome to AutogeekOnline!


:welcome: