Hard Water Spots on Car Paint: Causes & Fixes

Client was bothered by these water spots and tried consumer grade products to get it  out. The paint could have been affected by acid rain or a result of improper washing/ drying while in storage at a dealership and/ or previous owner. 

The effects were largely isolated to the roof, hood, and back glass and raised flat/horizontal surfaces, on the bed and doors.

Why? 

Because these water spots can happen when acidic and/or hard water (water with high dissolved mineral content) meets and deposits on paint under high heat conditions and/ or direct sunlight.

Once the water evaporates, the dissolved minerals can stay behind, creating a deposit mark where the water once settled.

What do hard etched spots look like?

We call it etching once it seems to change the surface structure of the paint and is no longer setting on the top. The extent of the etching varies on climate, surface, and the duration it has been etched.

In this case, we did a light wet sand on the top of the vehicle. I did my least aggressive sand technique at 3000-grit, a cut stage to remove the etching and sand marks. The process was finished with a refining polish to level the finish from the cut.