Need help understanding polishing compounds


#1

I was over the Harbor Freight the other day and was looking at their assortment of polishing compounds. Such as this “green” one.

The reason I was looking, my poor Corolla is a victim of being manhandled. Badly mistreated. By me. On accident of course. I used one of those green scrubbing pads to remove some stubborn bird drop stains a while back, nothing else seemed to do any good, including what always seems to work gasoline. So I ended up with a half dozen quarter-sized scuff marks on the clear coat. The bird drop stains are gone, so there’s some good … lol. On a recent show a caller had a similar problem and Ray said they needed to be buffed out.

These polishing compounds at HF, there seems to be 6-10 different kinds. With the same package size. But in different package colors. Or maybe that’s the color of the compound inside. But what I’d really like to know is, not what color it is, but what is the difference between them? I was expecting to see that one has particles of 10 microns, and the other had particles 5 microns, and another had particles 0.5 micron, etc. Maybe there are two kinds with the same particle size, but one is aluminum oxide, one is silicon carbide, one is diamond, etc. But that’s not how they are labeled. Nothing like that. Instead they are labeled for what kinds of materials they are used to buff I guess. Plastics, metals, etc.

So anybody know what color compound I should I start my buffing with, and what color sequence should I progress as I work toward the finishing color?


#2

That polishing compound is used on stainless steel,chrome, brass, copper,steel,etc.

Or trim work on a vehicle.

You want a polishing compound for PAINT.

Tester


#3

You need to visit an auto parts store that sells painting compounds. Pepboys does, and I’m sure others do. They’ll be labeled by micron size, and the media will be the proper type.

Harbor Freight sells stuff for polishing materials other than paint, such as various metals; aluminum, copper, steel, etc. You do not want to use those polishing compounds. Go at your paint with an aggressive compound designed for polishing steel and you’ll quickly end up with a naked but well polished area on your hood.

But first, visit the local bookstore and pick up a book on painting cars. In general, you’re going to want to start with a larger micron size and work toward the smallest. But there are other things to know, such as pad types and uses, and how to use the buffer to prevent swirls. So get the book. It’s worth every penny the $10+/-.


#4

the common name is “rubbing compound”


#5

Bird droppings could be very abrasive and might eat through the clear coat, if your car has one. If this is the case, buffing will make it look better, but YOU will still notice it. Don’t ask me how I know.

I stay away from rubbing compounds unless I am using it on the yellowed headlight. Just use a cleaner wax and see what happens.


#6

Rubbing compound is not the same as polishing compounds. It’s the first step only, and only for the purposes of cleaning a painted surface in preparation for overspraying.


#7

About all I use is 3M and Meguiars but its not cheap. If real bad scratches you can sand with 2000 grit to get the scratches to a reasonable level. Then I would hit it with 3M Perfectit II rubbing compound. Then to a Meguires polishing compound-medium level. Then the swirl remover will do a nice job of taking out any polishing scratches before waxing. I use a machine buffer though. You can do small spots by hand but get the non-machine polishing compounds if doing it by hand. You’ll be into it $50-100 without the buffer. Just what I do.


#8

I’d avoid the guesswork and pay a body shop. Choose the wrong compound and you could use up what clear coat is left.


#9

Do you plan to buff this by hand or with a machine? What color is your car?

For removing (or at least reducing) scratches by hand, I generally use Turtle Wax polishing compound rubbed in no more than necessary followed by Meguiar’s liquid Cleaner Wax rubbed in harder. I also have Turtle Wax rubbing compound on hand, but I’m hesitant to use it except in the worst cases because of how abrasive it is. I can’t say if this is the safest approach for your case, but it’s worked for me so far.


#10

The polishing compound that you referred to at HF, is not for polishing a car…or any painted item.
These are used with a cloth wheel on a bench grinder for polishing different bare metals. Or sometimes a drill with a cotton wheel.

Yosemite


#11

Not a bench grinder. But on a polishing/buffing motor.

Notice how the motor is skinnier, and the shafts stick out more for better access to the buffing wheels?

Tester


#12

Isn’t this the person who said to wax a car and leave it on for a week before buffing it off ? Maybe that’s why he needs a polishing compound .


#13

Ok, I understand, those color buffing compounds aren’t for buffing car paint. I’ve already tried just using a simple wax job. Last spring. It helped quite a bit, but didn’t completely eliminate the problem.

Here’s another idea. HF also stocks this Meguiars Ultra Finishing Compound

Maybe some combo of that and 2000 grit wet dry sandpaper? I have some rubbing compound on hand already, I think by T-Wax. But I’ve only used that before for brightening up oxidized paint on my 40+ year old truck. It works pretty good on the truck, but seems a little too aggressive for something like this.

Years ago I had a similar problem, but not w/my car, with my watch crystal. It got scuffed up so bad I could barely see what time it was. I have to admit, it happened the same way, with one of those green pads … lol … Anyway, I guess I never learn . So what I did then, I asked the experts where I worked how they polish silicon wafers, and they told me they used diamond slurry. So I bought some of that from a specialty place, it didn’t cost much in the amount I needed, like 1 ounce, and it polished up the crystal so fast you wouldn’t believe it. And so clear, it looked like new. I just rubbed it lightly on the watch crystal with a cotton cloth is all. I’d be surprised if it took as long as a minute to finish the job.

I plan to do this job the same way, by hand. I have a powered buffer gadget but it seems like overkill, and not as easy to control where I’m buffing and where I’m not buffing. If I end up making the problem worse during the experimentation stage, I want to keep it contained to the original spots, not make larger ones.

Anyway, thanks to everybody for the good suggestions.


#14

If you look at the red arrow, it indicates the level of aggressiveness. Its number 4 so that is the same as the swirl remover. So thats a very light polish designed for the final round before glaze or wax. The only thing it doesn’t say if it is machine or hand applied. So that’d be ok but would take a while if by hand in particular. The other thing is 32 oz is a lot. The normal container at O’Reiley or someplace would be 16 oz for half the price. The 16 oz lasts me several years doing two cars twice a year.


#15

Thanks, good info. You can tell I’m a novice at buffing. I thought that scale on the left of the bottle w/the red arrow was to figure out how much was left in the bottle … lol …


#16

One thing about Meguires is that they have very confusing packaging and have been criticized for it. They finally put the arrows on instead of the numbers they used to use that no one could understand.


#17

Go here

http://www.autogeek.net/detailingtips.html

And read all about polishes, sealers and waxes designed for paint, not metals. Wander around the site for products and tips and such to make your old paint shine. (No, I don’t own stock in the site!)

You can buy much of the foam and wool buffing pads at Harbor Freight and sometimes the paint polishes as well (mine sells them).