Polishing pad with cutting compound VS cutting pad with polishing compound

[Ferris]

Howdy all,

Was wondering whats the difference between using polishing/soft/fine pad with rubbing/cutting compound results and effects VS using a cutting/firm pad used with a polishing/finishing compound or polish

[larry33]

That is an excellent question

[brettS4]

Here is my understanding of how the combinations rate in terms of cutting ability, rated most to least...

Cutting pad w. Cutting compound
Cutting pad w. Polishing compound
Polishing pad w. Cutting compound
Polishing pad w. Polishing compound

The two in question will be somewhat similar, and might work differently than this depending on a specific vehicle's paint. But the thing that might matter more than pure cutting ability is how well they finish out. And with most newer pad options you get better results with a cutting pad and polishing compound. So I would choose that combination and eliminate a polishing pad with a cutting compound entirely from the choices.

On the other hand, I have no idea what I'm talking about.

[shadwell]

I tend to think of the softness of the pad impacting how much the polisher is confirming to the panel profile..

Where as the product (polish or comppound) is primarily working in shear.. so high abrasive will be still be abrasive on a softer pad at the same rotational speed.. assuming same vertical load on the pads in all instances..

Means anything wth a compound will cut harder than anything with a polish....

Things get ramped up with tighter radius profiles as the harder pads will give much higher localised loads and more concentrated points of working vs a softer pad (again for the same applied load..)

I have done test sections on more radisused section previously to see if there was a marked difference to the flats.. in case i needed to change set up..
I found a small switch in technique allowed the same set up.. (ie faster passes and alot more dynamic with the angle of the poisher to suit the profile etc..)

Def a good question tho.. i wasn't sure so i tried on a family members car.. (super low risk as it was with a DA and their paint was flogged anyway)

[dcjredline]

To me none of that matters. What matters to me is what I see when doing test spots. You can guess and hope all day but a test spot or 3 will tell you for sure on the particular paint you are working on, nothing else can tell you like test spots can.

[dlc95]

I routinely use a "polishing" foam pad to cut, over traditional stiff pads.

Some vendors listed the pad as a "light cut/heavy polishing"

The reason is that it's a medium density, with fairly large, open pores. The surface is coarse, and fibrous. When the typical orange foam pads get soft after a little use, it's a lot smoother comparatively than the green (buff and shine).

I also tested this in the real world using both a Flex 3401, and a PC 7424xp.

Check out my gallery "Meguiar's Ultimate Compund, Porter Cable 7424xp, Green Hex Logic vs 1000 grit" in my photo album. There's a little write up on the combination too.

[RPM_BR]

I routinely use a "polishing" foam pad to cut, over traditional stiff pads.

Some vendors listed the pad as a "light cut/heavy polishing"



Me too. Polishing compounds evolved so much, that I hardly use stiff foams. Obviously there are cases when it will be needed, but medium density foam is always my first choice for cutting.
This personal choice changed the way I buy pads, before I would buy more heavy cutting than medium cutting, since cutting always degrade the pads faster, but now I buy more medium cutting pads.
Best regards

[Ferris]

Thanks everyone for all the input and information!

I hope soon Il have some friends cars that I can practice on.

So basically theoretically even if I go for a cutting pad and a polishing compound I should not expect any holograms since its the polish thats doing the work and not the pad? Even if lets say Im using a polish on a twisted fiber wool pad?

[dlc95]

Me too. Polishing compounds evolved so much, that I hardly use stiff foams. Obviously there are cases when it will be needed, but medium density foam is always my first choice for cutting.
This personal choice changed the way I buy pads, before I would buy more heavy cutting than medium cutting, since cutting always degrade the pads faster, but now I buy more medium cutting pads.
Best regards

Those green pads consistently picked up more paint for me. And I believe it has a lot to do with the cell orientation. On both the orange and yellow cutting foams, their pores are much smaller, and the foam formula much more dense than the green b&s/hex, or pink lc ccs. This is taken to an extreme with the purple LC kompressor foam which has even larger pores, and is still not as dense as the yellow and orange foams.

What's great is that you can use either according to your style. Guys who use the 15lbs of pressure, and slow the pad down via that pressure are going to get better results from the traditional cutting pads. It's needed to force the abrasives into the paint. I personally feel that those who prefer a lighter touch, and go for maximum pad rotation benefit from the more open cells of the green b&s foam. They're more "gritty" feeling. However, of they are used with pressure, they're slowed down, and the benefits of the foam are lost as rotation is decreased.

Could just be me. I do things weird. When I first got my PC on 2010 I used it like a rotary and struck through paint on a neighbors car using the green foam, and Meguiar's Ultimate Compound. This is after a few years of no burns or strike through using a rotary. Speed, and light pressure, and look out! I learned that day to use that combo with more respect and today feel that I can achieve my cutting goals with that combination.

[dlc95]

Thanks everyone for all the input and information!

I hope soon Il have some friends cars that I can practice on.

So basically theoretically even if I go for a cutting pad and a polishing compound I should not expect any holograms since its the polish thats doing the work and not the pad? Even if lets say Im using a polish on a twisted fiber wool pad?

Nah, the wool fibers on that type of pad are fairly aggressive, and will probably mark up the paint.

[dcjredline]

Ill say it one more time cause you didnt seem to have read it... You can guess and hope all day but a test spot or 3 will tell you for sure on the particular paint you are working on.

Not trying to be a douche but you cant just guess and generalize. You have to try it and see how it does. No one can tell you on the internet what will work and how well it will work on that specific car/paint condition.

[Zubair]

Real life experience trumps internet advice anyday. Do a test for yourself using both methods, analyze the paint after and you would have gotten to the truth faster than typing here and waiting for the responses.

[RPM_BR]

Those green pads consistently picked up more paint for me. And I believe it has a lot to do with the cell orientation. On both the orange and yellow cutting foams, their pores are much smaller, and the foam formula much more dense than the green b&s/hex, or pink lc ccs. This is taken to an extreme with the purple LC kompressor foam which has even larger pores, and is still not as dense as the yellow and orange foams.

What's great is that you can use either according to your style. Guys who use the 15lbs of pressure, and slow the pad down via that pressure are going to get better results from the traditional cutting pads. It's needed to force the abrasives into the paint. I personally feel that those who prefer a lighter touch, and go for maximum pad rotation benefit from the more open cells of the green b&s foam. They're more "gritty" feeling. However, of they are used with pressure, they're slowed down, and the benefits of the foam are lost as rotation is decreased.

Could just be me. I do things weird. When I first got my PC on 2010 I used it like a rotary and struck through paint on a neighbors car using the green foam, and Meguiar's Ultimate Compound. This is after a few years of no burns or strike through using a rotary. Speed, and light pressure, and look out! I learned that day to use that combo with more respect and today feel that I can achieve my cutting goals with that combination.

Thanks a lot for the info, Dan, I really appreciated.
It seems that, based on my limited experience and experimentation, that large pores/stiff foams should be used with higher speed settings and less pressure, and small pores more pressure and less speed.
There is a Menzerna white pad, not available in US, that is one of a kind, really small pores and stiff foam. It is as hard as a grey Rupes UHS pad. It is a good choice for the Fg400, a compound that due to its combination of solvents, it softens the pad. Hence, FG400 shouldn't be used with hard open pores pads, like Rupes cutting line, as Dylan pointed out.
The Menzerna pad line consists of a white for cutting, a yellow for polishing, a waffle black for finishing and a short fiber wool pad. The yellow, black and wool pad you'll find similar pads in US from the LC, B&S line, but menzerna white I've never seen anything like it.
I was wondering if the new Force line from Lake Country, the grey pad, will be more like menzerna white, hard stiff small pore pad.
Please apologize my diggression, and best regards

[Zubair]

The Menzerna white is fantastic and the best pad I have used on my PE-14.