Pad Size why 5.5 in.??

**M Porter** · 06-05-2012, 04:54 PM

I have a 2012 BMW that I have been polishing. I am new to this so I could be wrong, but it sure seems to have a hard clear coat. After getting frustrated over the length of time it was taking I have ordered 5 ½ pads. Will I notice that much difference dropping from 6 ½ to 5 ½ pads? What size of pads do most people on here use with a DA polisher?

Mike

**kronos** · 06-05-2012, 05:09 PM

Your technique is the most important variable, but 5.5" pads will help. I use 5.5" and 4" pads with my DA and rotary.

**BobbyG** · 06-05-2012, 05:12 PM

Hi Mike,

The 6 1/2" diameter pads a Porter Cable type dual action polisher in my opinion pushes the limit of the machine and this could be part of the problem.

I have the Porter Cable 7424 and found a world of difference when I decided to try Lake Country 5 1/2 diameter pads.

The Porter Cable 7424 style dual action polisher should come standard with 5 1/2 inch pads and corresponding backing plate.

Pads & Friction

The size or surface area does not directly affect the frictional force between two surfaces until downward force or pressure is applied. Reducing the pad size will only improve the mechanical efficiency of the machine.

The motor of your polisher produces some amount of power. The larger the pad surface area the harder the motor must work. Now, most will say "it's only 1 extra inch", but when it comes to surface area and friction your really talking about an additional 10 square inches. Now take a look at the difference between the 5 1/2", 6 1/2" and 7" pad...........Size does matter!

Surface Area - 5 1/2 pad = 23.75 in²

Surface Area - 6 1/2 pad = 33.18 in²

Surface Area - 7 pad = 38.484 in²

There is a direct relationship between the pad surface area and the polishers ability to transfer adequate power to the pad improving it's overall performance.

What products are you using?
What pads are you using?
What speed setting are you using for correction?

Here's some great information by Mike Phillips that will help you if you need it.

**RZJZA80** · 06-05-2012, 05:18 PM

Pad size matters less depending on the DA you are using. On a Griot's, you can do well with a 6.5" pad, but 5.5" is better since it fits and conforms better to the body of the car, it's curves, etc. plus poviding optimal cutting power. The PC is lower in power so using a smaller pad is optimal for it, 5.5" max from my experience, 4" is even better. It just depends on the DA you are using.

**Buckskincolt** · 06-05-2012, 05:35 PM

Originally Posted by BobbyG

Hi Mike,

The 6 1/2" diameter pads a Porter Cable type dual action polisher in my opinion pushes the limit of the machine and this could be part of the problem.

I have the Porter Cable 7424 and found a world of difference when I decided to try Lake Country 5 1/2 diameter pads.

The Porter Cable 7424 style dual action polisher should come standard with 5 1/2 inch pads and corresponding backing plate.

Pads & Friction

The size or surface area does not directly affect the frictional force between two surfaces until downward force or pressure is applied. Reducing the pad size will only improve the mechanical efficiency of the machine.

The motor of your polisher produces some amount of power. The larger the pad surface area the harder the motor must work. Now, most will say "it's only 1 extra inch", but when it comes to surface area and friction your really talking about an additional 10 square inches. Now take a look at the difference between the 5 1/2", 6 1/2" and 7" pad...........Size does matter!

Surface Area - 5 1/2 pad = 23.75 in²

Surface Area - 6 1/2 pad = 33.18 in²

Surface Area - 7 pad = 38.484 in²

There is a direct relationship between the pad surface area and the polishers ability to transfer adequate power to the pad improving it's overall performance.

What products are you using?
What pads are you using?
What speed setting are you using for correction?

Here's some great information by Mike Phillips that will help you if you need it.

Read the threads BobbyG posted above and answer the questions he ask and I think you will be on your way to solving your issues!

**M Porter** · 06-05-2012, 05:50 PM

I apologize I should have given a bit more info. I am using a Griot’s DA(not the Professional model

), with their orange pads and Megs 105. After a few frustrating hours, I sped up to near 6. Before this I was closer to 5 and applying a fair amount of pressure. I have slowed my arm speed to much less than Mike’s (in his video), with less pressure and seem to be getting better results. My order has just arrived (unfortunately not through AG, due to being a canuck) with 5 ½ pads and proper backing plate. I am very curious as to the difference in my time and labour. It makes a lot of sense when discussing the square inches, between the two. My first hobby (or love??) is playing snooker. The difference between a 6x12 and a 4 ½ x 9 table, dimension wise, does not sound like much. There is 75% more playing area on the larger table. So yes size matters. One last question, when I switch to Megs 205 should I stick with the orange pads?

Thanks for all the help.
Mike

**BobbyG** · 06-05-2012, 05:59 PM

Mike,

Meguiar's M205 is a nice polish that will remove 2000 to 2500 sanding grit marks. I'd try this using a primed White foam polishing pad and don't be afraid try M205 and a gray foam pad.

White Polishing Foam - Less dense foam formula for the application of waxes, micro-fine polishes and sealants. This pad has very light cutting power so it’s perfect for pre-wax cleaners.

Gray Finishing 6.5 inch Foam Pad - Composition is firm enough to withstand added pressure during final finishing to remove buffer swirls. It has no cut and will apply thin, even coats of waxes, sealants, and glazes.

**Buckskincolt** · 06-05-2012, 06:00 PM

What type pads do you have?
Typically you would change to a white? (depending on the pads for the color) polishing pad when switching to M205

**TornadoRed** · 06-05-2012, 06:23 PM

Originally Posted by M Porter

I apologize I should have given a bit more info. I am using a Griot’s DA(not the Professional model

), with their orange pads and Megs 105. After a few frustrating hours, I sped up to near 6. Before this I was closer to 5 and applying a fair amount of pressure. I have slowed my arm speed to much less than Mike’s (in his video), with less pressure and seem to be getting better results. My order has just arrived (unfortunately not through AG, due to being a canuck) with 5 ½ pads and proper backing plate. I am very curious as to the difference in my time and labour. It makes a lot of sense when discussing the square inches, between the two. My first hobby (or love??) is playing snooker. The difference between a 6x12 and a 4 ½ x 9 table, dimension wise, does not sound like much. There is 75% more playing area on the larger table. So yes size matters. One last question, when I switch to Megs 205 should I stick with the orange pads?

Thanks for all the help.
Mike

The Griot's orange pads do not have much cut but finish nice so keep them around for the Megs 205. What 5.5" pads did you get?
I have a Griot's DA and did a friend's BMW with a 5.5" LC Hydro-tech pad, Griot's #1 polish, speed 6, and had to practically stand on the thing to get any correction.

**dougaross** · 06-05-2012, 06:48 PM

Originally Posted by M Porter

I have a 2012 BMW that I have been polishing. I am new to this so I could be wrong, but it sure seems to have a hard clear coat. After getting frustrated over the length of time it was taking I have ordered 5 ½ pads. Will I notice that much difference dropping from 6 ½ to 5 ½ pads? What size of pads do most people on here use with a DA polisher?

Mike

I hope you didn't forget to get a 5" back plate