Although you have cleaned the exterior of your windshield and applied a protective coating to its surfaces, there may still be small white spots on it. These spots are called water marks and are caused by airborne minerals and other contaminants in rainwater or chlorinated auto wash solutions.
When hard water dries or evaporates, it leaves behind a mineral residue. When this hard water dries or evaporates on a surface, it leaves behind a mineral residue that cannot be removed by normal car wash methods. And the spots, or calcium deposits, harden over time and make glass rough to the touch. They also give your glass a rough texture. And these spots are tough to remove.
Hard water spots form on the glass due to a variety of sources, including overwashing a car with softened city water. A DIY wash can result in hard water spots. Professional car washes that do not treat their water supply can also create hard water spots. The rain may cause hard water spots as well. To remove them, try one of these methods:
To remove mineral deposits from the glass, mix equal quantities of water and white distilled vinegar and either put it in a spray bottle and wet the glass or soak a towel and apply it to the surface. Allow the vinegar to sit on the spots for at least five minutes so that the acidity in the vinegar can counteract the mineral deposits. Then wipe it off with a clean towel until the spots vanish. Repeat as necessary and increase the concentration of vinegar if the stains are stubborn.
2. Essential Oils
Essential oils are gaining in popularity for a number of uses. One that you may not have thought of is confronting hard water spots on your windshield. Mix a few drops of lemon or orange essential oil with water, apply to the glass with a towel or sponge, and allow it to soak in for ten minutes. Follow it up with an automotive glass cleaner. The oils’ antifungal and antibacterial properties prevent the formation of water spots and protect your car’s windshield from damage. Try it once a week to prevent hard water spots from developing in the first place.
3. Lemon Juice
To remove salt and other spots from auto glass, combine equal parts vinegar and water in a spray bottle. Spray directly on the glass. Fresh lemon juice works better than the bottled variety. Rub lemon directly on the glass or apply with a towel.
Toothpaste is a good abrasive for removing mineral spots from glass. Apply a small amount of toothpaste to the glass, let it sit for several minutes, and rinse with water. Follow up with an automotive glass cleaner to remove any remaining toothpaste residue.
5. Commercial Products
There are also several commercially available products that can be used to remove mineral buildup, which is available at a local hardware store.
Prevention is your best solution
For your car to remain in top condition, you’ll want to prevent hard water stains from forming. The best way to do that is by using one or more of these preventative measures:
Whenever possible, park in a garage or carport to avoid allowing the surface of your vehicle to dry out in the rain.
Treat water spots as soon as they appear to prevent them from setting.
Always keep your car in top shape by maintaining the paint and making sure it’s free of scratches. If you want to avoid water spots, make sure your car is free of scratches and water-repellent.
To remove residual water, wipe the glass or paint surface with a dry cloth.
To prevent water spots, use a product like Rain-X Complete Surface Protectant and Armor All ® Extreme Shine Wax on your windshield (and paint) at a full-service car wash. If you are a member of a car wash membership, you can make sure your car is treated as often as necessary.
Wax the paint and apply a coat of glass water repellant to the windshield.
Hard water spots on glass can be removed with some effort. It is best to avoid them in the first place by washing your car often or including a car wash service in your maintenance plan.