Washing Your Car Leaving Water Spots?
Most water contains some amount of dissolved minerals. When this mineral containing water dries, it can leave white spots on whatever surface it dries on. You can make a simple test of your home’s water to determine if it indeed will cause water spotting. Simply wash a clean clear drinking glass with tap water. Let it air dry on the counter. If you then see any whitish water spots or discolorations you can be certain the water supplying your home contains minerals. If you wash your car with this same water and allow any of that water to air dry on the car, you will get deposits of minerals on the paint. The deposits will reduce smoothness, clarity and overall gloss and will prevent you from getting the best shine possible
How do you avoid these deposits? Either get a water conditioning system installed in your home to remove all those minerals or allow as little water as possible to air dry on your car’s paint. After years of experimenting with cotton towels, microfiber cloths, chamois, synthetic chamois and similar drying materials, we have found that even with aggressive wringing all eventually become water saturated. At this point they cannot remove enough to prevent all water spotting. You can easily test your drying materials. Completely soak your material and then wring it out as best you can. Then wipe any mirror in your home with the now damp material. If you see any water beads on the glass you can assume you are leaving too much water on your car.
To remove the small amount of visible water that the saturated materials leave on the paint, quickly follow up with a soft dry cloth before the remaining water air dries. This should remove virtually all the water and greatly reduce the chance of leaving any mineral deposits. You may require 3 to 6 dry cloths depending on vehicle size.
Always move your vehicle into the shade after washing to prevent the sun from rapidly evaporating the water.