[blownaltered]

Originally Posted by Dan12GT Megs kits from the shelf are fine to use for most paint conditions. That is what I used on my recent paint correction project (you can check out my thread). You can really get into the science of it by checking out what auto geek as to offer and the explanations behind each product. The best way to feel if your car needs clay is to run the back of your fingers along the paint after a complete wash (dawn for best results). If you feel minor rises or "pips" in the paint it needs clay! Also if you are having a hard time feeling for that, grab a plastic sandwich bag, place your hand inside, and feel over the surface of your paint. The bag should magnify your contact patch with the paint to feel the deep contaminates. Also, don't ever ever use water or a water/soap mix! Why not water? * Water does not provide any lubricating qualities. * It might seem like it does at first but it dries rather quickly and you will find yourself working harder to remove the mess that water / clay produced. * Because water doesn't provide any lubricating aspects it is VERY likely you will hit a dry spot and send the clay bar flying from the paint surface. If it hits the ground it is done! No mater how clean it might look that clay bar should never touch your paint again. If you put a clay bar back on the painted surface after it has touched the ground or a dirty surface you are asking for trouble by creating scratches. * Water can also cause the clay bar to rub apart or deteriorate because it does not have any lubricating qualities to it. This could prove detrimental in your efforts and cause the clay bar to be very ineffective. Why not a soap/water mix? * The main reasoning behind this is because the soap will generate too slick of a surface generating a layer of soap to thicken between the paint and the clay bar, not allowing the clay to retain its abrasive qualities to remove defects, making it almost completely ineffective. It might feel like the clay bar is gliding smoothly but it is not doing its job by removing deep contaminates. Think of it as a car hydroplaning. It might feel like you are on the road until you go to make a turn or try to slow down and nothing is responding. USE DETAIL SPRAY! * This will provide the lubricating qualities as needed to perform an effective job while not over lubricating the clay to provide the lubrication needed to remove harsh contaminates. Work section by section buffing off the detail spray as you go. Once you are finished the paint should feel as smooth as glass! Proceed to feel the paint again with the back of your fingers or via a plastic bag again, and you will be thoroughly satisfied! Then, you are ready for a deep polish!

Thanks for that. It was a very informative read.