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Proper Use of the Clay Bar

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Clay removes all traces of wax and then grinds out any impurities from the paint. This is why the finish is nicer after clay and why wax applies easier.

Wax won't keep fallout from collecting on the car, but it will prevent it from coming into contact with the paint and oxidizing it. I suppose my last comment is only 100% true if you occasionally strip the wax from your car to reapply.
 
I’ve often heard it said that clay removes wax but I’ve never heard a convincing argument as to why. Come to think of it, I’ve never heard any argument as to why.

Claying removes contaminants that protrude above the paint’s surface. You easily feel the drag when clay is abrading the protrusions but it feels like it’s gliding on wet ice once the contaminants are gone.

That marvelously slick glide comes from the fluid “bearing” of the clay lubricant. The wax layer is microscopically thin and absolutely smooth to the surface. I can’t prove it, but it seems as though it should be orders of magnitude thinner than the fluid bearing thickness. Not to mention the fact that it’s actually smoother than the paint itself.

The wax layer has nothing for the clay to “grab onto” so it should stay relatively intact below the fluid. You can feel it for yourself. Claying a pristine finish that has just been waxed creates far less friction drag than simply wiping a towel on the finish. Wiping with a towel doesn’t remove the wax from the finish (not completely anyway) so I don’t see why claying should.

Obviously, if you’ve waxed over some chunk of contamination that’s protruding above the finish, claying will remove any wax on the protrusion as it’s grinding the chunk flush. If the wax sticks to the contaminant more than the finish then I would agree that the finish below the contaminant is left exposed. If the area of contamination is significant then yes, you will leave a significant area exposed. That’s probably better than leaving it contaminated.

While wax does provide protection against the environment it’s not impenetrable armor. Some percentage of the water spots, bird bombs and general gunk that lands on your car will be strong enough to overwhelm anybody’s wax. If you want a finish to last, wash it often, wax it regularly and remove any concentrated contamination immediately.

How often to clay is a balancing act. It’s your tolerance for crud verses the rate crud builds up on your car. Everybody’s environment is different and everybody’s personal preferences are different. There’s no hard and fast rule. A couple of times a year seems to be popular. I tend to go by feel, which seems to be getting more often (as my personal tolerance level is dropping).


PC.
 
I suppose by the time you clay a car, much of the wax has already been worn off through washing and general abuse. At a Meguiar's clinic I attended, the instructor stated that wax is so thin and relatively fragile that clay will easily remove any traces still left at the time of detailing.
 
Well guys:
Everybody has their opinion about things , but I am here to tell you , I hav eone customer who restores prewar Rolls Royce's to museum quality. They keep a clay bar in their shop for those occassions when some element might be in the air that adhears to the paint. The clay bar is the safest tool to use when these times occur.

I can safely say that using a clay bar no matter how often you wax you ride, it will do nothing but good to the surface of your vehicle, as it conforms to the contour of your vehicle and only removes the contamination on the paint.
 
I agree it won't easily do harm. But even the act of washing will put wear on the finish. Therefore it's best to keep the paint as well protected as possible, meaning wax and a car cover, to minimize the need to scrub off unwanted materials.
 
Steve_S said:
…At a Meguiar's clinic I attended, the instructor stated that wax is so thin and relatively fragile that clay will easily remove any traces still left at the time of detailing.
Click to expand...
Yeah, I’ve heard them say that too. But they’re also highly conservative and tend to err on the side of caution with their recommendations rather than try to explain complex phenomena. Until I see some sort of objective evidence or at least hear a rational technical argument as to why I won’t be convinced. I’m stubborn that way.


PC.
 
Well, as stated above, I'm a clay advocate for cars driven in normal use. However, I can understand how clay would remove wax. The clay is and abrasive. Granted, it is about the finest, least harsh, safest abrasive you can use on a finish, but it is an abrasive. The fact that it is used with lubrication does not change that. Wet sanding is done with lubication as well...in fact, I use the same type of lubrication with both- soapy water (dish detergent with wet sanding, car wash detergent with clay). The lubrication does not prevent the sandpaper from cutting and it does not prevent the extremely mild abrasive action of the clay.

That being said, clay is not enough of an abrasive to be a problem unless you go nuts with it and use it too often (once a month is too often in my book- as I said, once or twice a year is more like it). When I clayed earlier this week (Tuesday between the hours of 5:30 a.m. and 7:00 a.m. to be exact)- there was no wax left on the car when I was done, at least none that I could detect by feel- I know the difference. It was smooth as all get out, but clean, squeaky clean- a waxed surface is not squeaky, so to speak.

However, that's OK- that why I do it in the spring. I follow it withe 2 coats of wax and I'll be waxing regularly until the snow flies...and then, believe it or not, I'll put a coat of Nu Finish on for winter (this is my everyday car). You should see the finish- the car is 10 years old and it looks better than the cars of my friends less than 2 years old.
 
lawguy said:
.... The clay is and abrasive. Granted, it is about the finest, least harsh, safest abrasive you can use on a finish, but it is an abrasive. The fact that it is used with lubrication does not change that. Wet sanding is done with lubication as well...
Click to expand...
But that’s not how clay works. Clay isn’t abrasive in the same sense that sandpaper is abrasive.

Sandpaper’s abrasive particulates are bonded to the surface of the sheet and project outward, toward the finish. The act of sanding forces the exposed particles into the finish, where they exert forces higher than the molecular bonding strength of the bulk finish material. The lubricant makes for cleaner cuts and carries away the swarf.

The abrasive particles in clay are held inside the clay. They don’t project out. The clay fills in the voids between the particles, presenting a smooth surface to the finish. The smooth surface of the clay rides on the lubricant film over the smooth surface of the finish (and possibly, I would argue, over the smooth surface of the wax layer).

When the clay comes to a contaminant that projects above the finish the contaminant is forced into the clay (the exact opposite of sanding) and by forcing itself into the clay presents itself to the abrasives held within. The contaminant is abraded until it is flush to the finish.

It’s easy to demonstrate how non-abrasive clay is to a finish. If you have a finish with the very slightest of swirls try claying them out. They won’t go anywhere. The swirls in most peoples’ paint come from the rags and whatever they use for washing and waxing. People who wash and wax their cars regularly for years will usually have paint that’s intact but full of swirls and scratches. If the clay can’t even remove the finest of those swirls that are caused by continual washing and waxing, how can it be abrasive enough to damage the finish, even over the very long term?

While it’s easy to demonstrate how gentle claying is to the finish it’s much more difficult to get a handle on how it affects wax. There simply aren’t any reliable, objective techniques that we can use in our own garages to assess the condition of a wax film. (I haven’t heard of any laboratory techniques that give direct quantitative measures of wax film integrity either.)

The above is a macroscopic view of the clay process. I’m sure there are secondary subtleties. There may well be some sort of boundary layer/surface tension/God knows what affect that does cause degradation of the wax film. But until I see it demonstrated of explained I’ll still consider it an unknown.

The “squeak test” you mention does give some subjective indication and anyone can perform it at home. Unfortunately, it’s only and indirect indicator and it’s highly unreliable. I’ve applied multiple waxes side by side on a pristine, freshly compounded panel and not only did they each squeak differently, but some would pass or fail with only the slightest changes in technique.

So where does that all leave me?

Well, since claying doesn’t harm a finish in any way I do it often. I do a lot of “spot claying” on very small areas when I see obvious contaminants. Since I still don’t know how claying affects wax I err on the safe side and generally wax after claying.

Some time ago, I got to the point where I clay every time I wax. Now I’m starting to crossover to where I’m waxing more because I’m claying more.


PC.
 
An excellent article by DavidB.

It’s interesting to note that PremiumAutoCare.com’s parent company, The Perfect Shine, LLC., sells a clay for which they make the claim “Removes the dirt, not your wax!”


PC.
 
Ok guys;
The clay bar is a surface preparation bar, the takyness removes the contamination by pulling off any residual attached to the paint, also pulling off any wax residue that may be on the top of the paint. Wax the car after using the clay bar, useing the KISS theory, cars should not only be a necessity in life, but fun to own and a joy to drive. It seems that we are getting away from the fun of working on the car by writting to much about what to do, I am going to go clay and wax my car. I'll be done in about a hour and a half, thus relaxing as I do the work and drifiting away into the shine of my paint, letting go of the four women who dominate my life and the mother-in-law across the street.
 
sooooooooo... in a nutshell, Clay Bar will remove oxidation from paint?
 
I hope that this picture is big enough to show how well it works, as my little nephew is pointing out below:
 
Nunyas said:
sooooooooo... in a nutshell, Clay Bar will remove oxidation from paint?
Click to expand...
No, it won’t.

Clay removes stuff that’s stuck on the surface of the paint. Oxidation isn’t stuck on the surface. Oxidation is the surface. It’s paint that’s been chemically altered by environmental exposure.

To remove oxidation you’d use products with abrasives that shave microscopic particles off the surface until you get down to the good paint.

Even if you plan on cleaning off oxidation with a compound or abrasive polish it’s a good idea to clay first. That will leave the finish fully exposed so the chemical can do its job.

You might think that the abrasive chemical would remove surface contaminants and eliminate the need to clay but the fact is that some gunk is just better suited to claying off than polishing off. Just for fun I’ve buffed on areas that were half clayed and half not. Even on a finish that was pink from oxidation and restored to bright red by polishing with a rotary buffer there were still bonded contaminants left afterwards on the half that wasn’t clayed at first.


PC.
 
thanks! that's what I needed to know /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
Just did my wifes car and my truck. Wish I had known about this stuff long ago. Surface looks and feels like new.
 
well, there's a job I could have done months ago. Just did my wife's Beetle - I'd been putting it off assuming it was hard and time consuming - talk about instant results! thanks all for teaching me about this

"wax on, wax off"
 
Hello Everybody:

I am posting what started out as a very oxidized surface vehicl that I bought strictly to display the clay bar and wax. I removed all surface contamination with the clay bar, and oxidation with the carnauba wax. Judge for yourself, but the wax has no abrasives n it, but does remove the cloud of oxidation. All of this was done by hand. THis was done awild ago, and has our old labels.Nice to see everybody giving their opinion about the claybar.
claybar.jpg
 
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