Sprinkler Hard Water Stain Drops on Windshield

Old 08-20-18, 02:41 PM
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Sprinkler Hard Water Stain Drops on Windshield

I have off street parking and unfortunately there is a sprinkler right next to where I park my car. Over the months, half of the windshield and the passenger side window have both developed hard water drop stains

I tried rubbing alcohol and vinegar but the stains are still there.

Any ideas other than hiring a professional?
Old 08-20-18, 03:25 PM
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I use #0000 steel wool and a glass spray (I like https://www.amazon.com/dp/B07B4XGW23/)

Follow up with just the spray and a lint free cloth.

Use care with the steel wool around the edge so you don't scratch anything.

Note that if the chemicals in the water have had time to etch the glass you're out of luck.
Old 08-20-18, 03:44 PM
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If it's doing that to the glass what is it doing to the paint ??? .....
I would cover that sprinkler or find another parking spot
Old 08-20-18, 06:51 PM
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I have had good luck using rain-x to remove water spots. I am not sure how well they will remove hard water spots but you could try it.
Old 08-25-18, 02:19 PM
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Might just put the vinegar on a towel, let it sit on the windsheild to give the acid more "hang time" to dissolve the deposits.

The mineral contaminants might have actually etched the glass, what you think are spots can be more than just a surface contamination.

So if that's the case, Bar Keepers Friend Soft Cleanser can be effective for this. It contains Oxalic acid as the its main ingredient. https://www.barkeepersfriend.com/cle...soft-cleanser/
Does have a very mild abrasive, but would be ok for occasional use and may be required to remove the surface etching aspect of the contaminants.

A "pro" would probably use this...

Works well with hand application, as many compounds need a buffer to work well. I have used it with success (and now have a good strong arm from hand polishing). With any polish, just make sure you start with a clean windshield so there is no surface grit inadvertently abrading the glass while scrubbing away with a foam pad followed by a finishing scrub with a microfibre cloth. Then wash off the windshield again with soap, rinse and enjoy a clear windshield.
Old 10-20-18, 08:43 AM
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#0000 steel wool worked best on the windshiled

Tried vinegar, tried barkeeper's friend soft and was able to remove only a little bit.

Tried #0000 steel wool after spraying the windshield and side window with simple green diluted solution and it worked like a charm.

Needless to say, I am no longer parking next to the sprinkler.
Old 10-20-18, 08:55 AM
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Vinegar is a very weak acid. I imagine you would have to keep the glass wet for a day or more to see much result. You could try a stronger acid. Perhaps a diluted solution of muriatic acid. I have used it to remove mineral deposits from many items. Since you dilute/mix it yourself you can create the strength you need. A muriatic solution won't harm the glass but all bets are off if you get any of it on metal or rubber trim or the painted finish. The acid might not harm those surfaces but I have never tried it.

Be careful. Muriatic (hydrochloric) acid is the strongest acid you can commonly buy and must be handled properly so read up on safety precautions. I can't stress this enough. It's very strong acid and not something to treat lightly. Have a water source handy when mixing in case you get any on you so you can immediately rinse it off with lots of water.

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