Background
Clay bar products are most frequently used to remove paint over spray or contamination on a car. Contamination consists of tiny metal shavings from rail dust, brake dust and industrial fallout. This contamination affects all paint finishes and can cause serious damage when left untreated. Paint contamination can be felt as a "rough or gritty" texture on the paint's surface and can lead to tiny rust spots.
There is no wax, natural or synthetic, or any chemical treatment that can prevent or protect against this contamination. Compounding with an abrasive polish may remove this contamination but it can only be performed a few times before removing too much of the top, clear coat finish.
The solution to this problem is a clay bar, which safely removes over spray, and industrial fallout by "pulling" it off the surface. What differentiates a clay bar from other abrasive polishing or compounding solutions is that it does not perform any abrasive actions.
When clay bars were brought to the United States several other usages were found for them. Clay bars were found to be effective for removing over spray, tree sap, acid rain & water spots and a variety of other surface contaminants.
Today, professional detailers and body shops use clay bars as a simple, safe way to remove over spray and surface contaminants from painted surfaces, including chrome and glass.
How to use clay bars:
The clay bars are used in conjunction with either soapy water or a spray detail product as a wetting agent for the gentle rubbing of the paint surface with the clay. This process is similar to wet sand paper procedures. Clay bars should always be used on freshly washed, clean surfaces. Dirt on the surface could cause scratches.
It is recommended you start out by working on a small area of a few square feet at a time, gliding the clay bar on the paint surface misting the paint surface with the soapy water or spray detail lubricant. At first you should feel a slight resistance on the surface when running the bar over the paint. As you go over the same area repeated times you will feel less friction until the surface glides smoothly. When the bar moves freely you are done. Wipe the surface with a clean dry towel and continue in sections until the entire vehicle is complete.
As the bar becomes soiled, simply pull, stretch and refold to expose a new, clean side. When the bar becomes totally soiled (dark colored) discard it. Typical life span of a 4 oz. bar is about 10 to 12 cars. If a bar falls on the ground immediately throw it away, and use a new bar. Failure to do so can result in scratches on your paints surface from picked up debris. Upon completion, spray the bar with lubricant and store in an airtight container or zip-lock storage bag.