Clay bar theory
Following on from the guide to removing bug splatter and tar using chemicals, we will look to using car specific clay bars to clean the final bits of dirt off of the paintwork. We will therefore pick up after a treatment with Tardis, with few contaminants left:
A clay bar is used as a firm, flat surface that is run across the paintwork with a liquid lubricant used to mitigate damage to the car. The firmness will catch on the few remaining contaminants pulling them into the clay bar and off the paint. The obvious risk is that clay does not have a pile (like microfibre towels) so the dirt stays on the surface of the bar and therefore any dirt will be exposed to the paintwork while the clay bar is used.
The steps before this such as a good wash and chemical treatment will mitigate the risk by getting rid of the vast majority of contaminants. The other safety net is that we will work in small areas, frequently kneading the clay to reveal a clean surface.
Clay can be used on the paintwork, light covers, glass, wheels, virtually everywhere. If using a bar on wheels then do not recycle this bar and use for bodywork again!
How to use a clay bar
Clay can damage the paintwork if not used correctly so please be careful. To clay a car you will need a bar of your choosing and a suitable lubricant – usually quick detailer. My preference is Bilt Hamber clay, this is the only clay I know of that uses water as lubricant which is great on the wallet. I’ve also used Meguiars clay with Quik Detailer.
I usually cut the bar into pieces about a square inch in size and a centimeter thick, this is usually enough to do a car (or half a car if it’s particularly dirty!). Before making contact with the car, knead the clay bar until it is warm and malleable (can help to stand in hot water for 15 minutes). Form into a flat surface that we will use on the car.
Working in an area around 9 square inches in size, spray a generous helping of lubricant onto the surface of the paint and place the clay bar on top of this. Using finger light pressure, pass the bar over the area. You will feel the bar catch on the dirt the first few passes but this will subside and it will glide over the paint. This is when you know you are done with an area, as there is nothing left to pick up. The paint is perfectly clean.
As the clay picks up dirt the surface becomes soiled, in order to prevent doing damage the bar is kneaded which will reveal a clean surface. Eventually, the bar will become completely soiled, you will know as you won’t be able to knead to a clean surface. At this point dispose of the bar.
Note: If you drop the clay bar on the ground DO NOT use it again – bin it immediately. Too much dirt will be picked up on the bar.
As you work round the car in 9 inch areas you will leave a residue behind of lubricant and any diluted dirt. I usually wipe down each panel with quick detailer and a microfibre as it’s completed before moving on to the next section.
Work your way around the car panel at a time. If it is taking too long for you, you can always do the car in sections over a number of cleans.