Bit of a noob question, but why compound before polish?

[Niko Molina]

Compounding and polishing are about the same thing. Only difference is the aggressiveness, correct? Compounding and polishing BOTH cut into the paint, but compounding essentially cuts deeper.


Shouldn't one polish FIRST as a 'first attempt' to try and get a light scratch out, remove some oxidation, swirls, etc. and then if the polishing does NOT work, then 'up' the aggressiveness into the compounding stage.

Yet detailers start off aggressive/compounding first then move to polishing... then sealant then wax (or what-have-you).

[TurboToys]

a good detailer will always start as light as possible. most test out a few different combinations on bad spots to see how aggressive they need to go to get the correction they need. and then repeat it for the rest of the car.

if someone just starts out with a super heavy cut just to "be sure", then don't let them touch your paint because there wont be any left next time.

[Niko Molina]

a good detailer will always start as light as possible. most test out a few different combinations on bad spots to see how aggressive they need to go to get the correction they need. and then repeat it for the rest of the car.

if someone just starts out with a super heavy cut just to "be sure", then don't let them touch your paint because there wont be any left next time.

That's what I'm saying man. How come people compound before they polish?

[allenk4]

That's what I'm saying man. How come people compound before they polish?

We don't every time

If you are working on a piece of wood, you could start with sandpaper and make it whatever shape you want. Using a saw or lathe or chisel first to get it close to the shape you want; the final result will come much quicker.


We do a test spot using the least aggressive methods 1st

The test spot dictates what you start with and what you finish with.


If you can see swirls with you naked eye, you know that the paint needs to be polished. What you don't know for sure is how deep the defects are and how hard the clear coat is.

In some cases a few passes with light pressure and a medium polish on a white pad will give the correction you want.

In other instances, what appear to be the same type of swirls can require 6-8 passes with heavy pressure and an aggressive compound on an cutting pad (MF, Wool, Orange, PFW).

The "and what you finish with." portion relates to the fact that some paints will finish LSP ready after a fairly aggressive compounding and do not need the 2nd step of polishing. Some paints require aggressive compounding to remove RIDS and heavy swirls; followed by polishing to remove the smaller defect left behind by the compounding step.

[jamesboyy]

Sorry for intruding, though you don't always have to compound a paintwork if you take care of your paint , use a light polish at the beginning of spring/summer and proper gentle detailing methods now if you don't take care of your paint yes you will have to compound cause a polish is not strong enough to remove mostly every single swirl scratch etc and while it cuts more you don't keep working on the same panel a few passes and you move on so there is skin( clear coat) left for a later date... this is just my eight cent

[Paul A.]

After doing some test spots many times you resort to a more aggressive approach due to the paint not responding as well to a less aggressive "polish" attempt. When that happens and you need to step it up to a more aggressive combo of product and/or pad to correct the paints imperfections you will then need to level the surface imperfections left from compounding. You polish after compounding to remove the finer imperfections, remove any hazing or holograms and to refine the shine and gloss.

That is not to say you always compound. Some jobs i've had (e.g. Soft black Honda paint) a polish with a very light approach was all that was needed. On the other hand, the Black Lincoln Navigator i have this week needs some serious compounding with a wool pad and will definately need some finish steps after i compound to maximize the gloss and insure the paint is as flat and level as possible.

[brondondolon]

I've never started out with a compound. Some one starting out with a heavy cut compound without doing a test spot either has no idea what they are doing or have such a good eye and knowledge that they already know how hard the surface is and how deep the scratches are but that would be really rare and if someone was that good I guarantee they still might do a test spot.

My combo of choice is a LC Orange flat pad with WG TSR 3.0 it seems this combo can be worked to remove deeper scratches or as a light polish.

Sent from my HTC6435LVW using AG Online

[DogRescuer]

That's what I'm saying man. How come people compound before they polish?

Sometimes honestly its lack of knowledge or experience or on the other end its lack of patience which I need more off

[c8n]

That's what I'm saying man. How come people compound before they polish?

There are other variables that determines the overall aggressiveness of an approach such as pad selection, pressure and etc. Chemical used is not the only determining factor.
Having said that, I will go on to say that every paint will react differently. Sometimes a compound like M105 on a white pad can do wonders and finish off LSP ready.

[Lakeside Detail]

That's what I'm saying man. How come people compound before they polish?

A compound is necessary to correct defects on car that's swirled badly. A compound will correct much faster than a polish. The idea is to make 6 section passes and get good correction. Say you make 6 section passes with a polish and get 30% correction. You would then have to make 18 section passes on the same 2x2 foot area to achieve good correction. Those numbers were just a example...

That's more wear on your pads, machine, body, and it takes a lot more time and polish.

[Mike Phillips]

Compounding and polishing are about the same thing. Only difference is the aggressiveness, correct? Compounding and polishing BOTH cut into the paint, but compounding essentially cuts deeper.


Shouldn't one polish FIRST as a 'first attempt' to try and get a light scratch out, remove some oxidation, swirls, etc. and then if the polishing does NOT work, then 'up' the aggressiveness into the compounding stage.




You are correct. I have an article that explains this in detail. This practice is called,

"Use the least aggressive product to get the job done" (http://www.autogeekonline.net/forum/ask-expert-featuring-mike-phillips/28505-use-least-aggressive-product-get-job-done.html)

It's also covered in all my how-to books, see my Signature Line at the bottom over every one of my posts.







Yet detailers start off aggressive/compounding first then move to polishing... then sealant then wax (or what-have-you).




Two reasons for this,

1: Some detailers have a lot of experience and upon evacuating the condition of the paint they know based upon experience that they will need a true compound from the very start to accomplish the goal for the project they are working on.

I start with a compound for some of my projects.




2: New advances in abrasive technology have so dramatically changed compounds that now you can safely start with a compound without removing too much paint.

I explain this in detail in this article,

The SMAT Pack - Everything you ever wanted to know about Meguiar's SMAT products... (http://www.autogeekonline.net/forum/hot-topics-frequently-asked-questions/23561-smat-pack-everything-you-ever-wanted-know-about-meguiar-s-smat-products.html)


Below is just a portion of my article, I recommend clicking the above link and reading the full article.

Now look for the par where I talk about a Monkey Wrench :D



DAT - Diminishing Abrasives Technology
Diminishing Abrasives are a category of abrasives that actually break down, pulverize and disintegrate into nothingness as you work them against the paint.

For example, a diminishing abrasive will start out a certain size and/or shape, then under pressure over time as they are worked against the paint they will actually breakdown or break apart. This means they start out aggressive and thus aggressively abrading the paint, as they are worked under pressure over time they begin to break down and as they breakdown their aggressiveness level is reduced to the point that when correctly worked they are completely broken down and all you have left is a mixture of spent or used-up diminishing abrasives and the carrying agent or base they were embodied in to start with. There's also a certain amount of removed paint in this resulting mixture.



SMAT - Super Micro Abrasives Technology
Super Micro Abrasives are as the name states microscopic in size and do not break down like diminishing abrasives. While they may not breakdown like a diminishing abrasive, there does come a point where there effectiveness falls off in performance, my guess is that this is a cumulative effect of the base formula they are embodied in dissipates while particles of removed paint build up in the residue adulterating or diluting their effectiveness.

Just to note, this same adulterating or diluting effect takes place with any abrasive product because as the abrasive remove small particles of paint, these small particle of paint join into the mixture thus changing the ratio or percentage of abrasives to the base formula.


What's the practical difference?
The biggest difference that I can share is this, with diminishing abrasive technology you MUST work the product until the abrasives have completely broken down to insure you don't leave any swirls in the paint. The reason for this is because if you stop buffing before the abrasives have completely broken down then they are still cutting or abrading the paint, thus leaving swirls in the paint.

This isn't really a problem because most diminishing abrasive products when used correctly will break down over a normal buffing cycle, (period of time and number of passes), to sufficiently break the abrasives down. It's usually only an issue for people new to car detailing who are learning as they go.


With Super Micro Abrasive Technology, theoretically, because the abrasives don't break down, or more specifically because the abrasives don't break down like diminishing abrasives break down, you can stop anywhere in the buffing cycle without leaving swirls caused by the abrasives. This would tend to make SMAT products more "Bubba-Proof" with an easier or more flat learning curve.

Because the abrasives don't break down like traditional diminishing abrasives, and from experience leave a very clear, scratch-free finish whether you're using the most aggressive or the most non-aggressive products, this new technology kind of throws a monkey wrench into the philosophy of,

"Use the least aggressive product to get the job done"


Notice in the above statement I used the word aggressive, not abrasive.

This is how the statement is supposed to be written because there are more factors involved besides just the liquid chemical that contribute to how aggressive a process is, for example, your application material can be a HUGE factor as to how aggressive your choice of products are. I just point this out because I see others typing the above quote and often times they write,

"Use the least abrasive product to get the job done"


While the meaning is close, it's not exact as you can use products that are not abrasive at all to accomplish a task and still be following the philosophy.

But I digress... back to the topic at hand...


Why it's important to use the least aggressive product to get the job done?
The idea behind using the least aggressive product to get the job done is to remove the defect or defects while leaving the maximum amount of paint on the car.

For any Newbies reading this, anytime you remove a defect or defects like swirls, scratches Type II Water Spot Etchings, Type I Bird Dropping - Topical Stain Etchings, Sanding Marks after wet-sanding, you must remove some paint from the surface until you level the surface of the paint with the lowest depths of the defects you're trying to remove.

So removing below surface defects means removing paint.

That's normal and acceptable but the problem is paint is thin and from what I've seen over the years getting thinner. That means you and me don't have a lot of room for error and for decades, dating back to the Model T, the philosophy of,

"Use the least aggressive product to get the job done"

worked and made a lot of sense. Paint is thin and you only want to remove as little as as you have to in order to remove the defects so your paint will last over the service life of the car.

Now let me tie this train-of-thought together with SMAT products and why it throws a monkey wrench into traditional thinking.

Because the abrasives used in SMAT products don't break down in the same way diminishing abrasives break down and tend to leave a scratch-free, high gloss finish, (no matter which product you're using), this means you apply them and then only work them till the defects are gone.

Once the defects are gone, (and you visually see this as you work an area), you then stop working the product and wipe off the residue and move to the next step or a new section.

It's this ability to stop when the defects have been removed instead of stopping after the diminishing abrasive have broken down that throws a wrench into the old tried and true philosophy of using the least aggressive product to get the job done because theoretically you can start with the most aggressive product and because you stop after the defects have been removed you achieve the same goal as you would have achieved by using the least aggressive product to get the job done but you can usually do it faster and more effectivley... AND you leave the same amount of paint on the car.

With diminishing abrasives, it could be that you've removed the defects but if you removed them before the abrasives fully broke down, you must continue to work the products to avoid leaving swirls in the paint because the abrasives are still abrading, this means you're removing paint you don't have to remove. At least that's the theory I'm presenting in this article.


Make sense?


IF not, then chew on the ideas presented above and if you're still confused then post your questions to the forum! :D




Good question Niko... it shows you're thinking...


:dblthumb2:

[WRAPT C5Z06]

Shouldn't one polish FIRST as a 'first attempt' to try and get a light scratch out, remove some oxidation, swirls, etc. and then if the polishing does NOT work, then 'up' the aggressiveness into the compounding stage.


Always start wit the least aggressive first. Move more aggressive accordingly. Simple as that.