Water with high mineral content, such as calcium and magnesium.
Why do hard water spots form on glass?
When hard water contacts glass and the water evaporates and the mineral deposits are left behind on the surface.
What does hard water do to glass?
Dried hard water on glass leaves unsightly mineral spots which are very hard to remove. Since glass is a porous material these sometimes corrosive minerals can get trapped in the pores of the glass doing unfixable damage to your windows.
What is the best way to remove hard water spots from glass?
The hands down best cleaning agent to get rid of the hard water deposits on glass is to use Whink brand Rust Stain Remover. This magic little bottle can be found locally at any convenience store and is the best-kept secret for removing hard water spots.
Make sure to wear latex gloves when applying as this chemical is toxic and can damage your skin. Simply pour some of the liquid on a paper towel and start wiping your window in a small 6 by 6 inch area. Let it stand for a bit and evaporate to the point where it turns hazy. Go over the same spot with the damp paper towel and keep rubbing until the spots disappear and you can visually see the shine back in your windows. It may take 40 to 50 wipes in one spot to remove some bad deposits on the glass. Continue with the rest of the windows the same way and you will be amazed at how this product destroys those mineral deposits.
Take caution to not get this cleaning supply on your rubber seals or paint as it may have an adverse reaction to it. There are horror stories on the internet of this product destroying seals and paint, however, I have used this on my E30 and E46 with no issues at all. My rubber seals had the cleaning agent on it and no reactions occurred that destroyed anything.
Other techniques to remove hard water spots:
- Use half water half vinegar mixture to wash windows
- Clay bar
- Pure white vinegar
- Buff with lemon juice
- Rubbing alcohol
- Rubbing / polishing compound
- Ammonia / Water mixture
- Steel wool (will not scratch glass, will scratch the paint)
How to prevent hard water spots:
- Filter the water before washing your car
- Dry the car properly before the hard water has a chance to leave deposits
- Ensure your car is waxed properly to create a barrier with the paint
- Rinse your car with pure distilled water
Before trying any of these techniques please makes sure to try them in an inconspicuous location. Ensure no damage is done to the surface before applying the cleaning technique to the rest of the area. We claim no responsibility for any damage that may occur.