Windshield Repair Forum

I was called in by one of the dealers today to have a look at a new replacement windshield. Upon lookking at it, it seem to have misty kind of marks all over it. They couldn't use it. I tried using windex and steel wool to remove it but had little success. Anyone encountered anything similar to this and have found a solution?

If its on the surface of the glass it could be " watermark", caused by the packaging the glass was in, becoming damp and leaving a chemical residue on the glass. Thorough polishing, using scratch removal tools, usually cures it. Ensure both panes of glass(inner & outer) are polished.

Wilz,

If what your looking at is like hazy splotchy patches, I'd say glass is defective and needs to be replaced. I use to see these come in my glass shop, nothing to polish out because defect is in the glass or laminate.

If its on the surface of the glass it could be " watermark", caused by the packaging the glass was in, becoming damp and leaving a chemical residue on the glass. Thorough polishing, using scratch removal tools, usually cures it. Ensure both panes of glass(inner & outer) are polished.

by Glasseye

Exactly.

Thank you both, Gentlemen.

If you look at the watermark and the DOT is 563, the windshield is from China and this has become a very common problem. If this is the case, it could be on the inside or out or both. PPG recommends removing it with a mixture of vinegar and water. We have found that using a slurry of cerium oxide by hand removes it quite easy, just a little elbow grease needed. Using anything abrasive might just cost you the windshield because if you scratch it, the installing company is probably going to be happy to sell them another windshield rather than warranty at that point.

Sydfloyd44, with the mixture of vinegar and water, what ratio would you recommend and do you hand rub into the glass with.............. or buff?

I haven't actually used the vinegar/water mixture since we do not keep vinegar around the shop. I would imagine a 50/50 mix would be a good starting point. Cerium oxide works good, just a bit messy! We have used cerium oxide by hand (rather than machine buffing) for a long, long time for removing water marks, acid rain and most anything else on the glass. Using a buffer to go over the outside of the glass would be fine, but we don't do large areas like that anymore. One time we got a bit of contamination of the wheel and scratched the heck out of a windshield. Cost us a w/s replacement. I would use the vinegar water the same as the cerium oxide, just put some on a paper towel and starting rubbing. "Digging" into the glass is not going to do any good, just light to moderate pressure should do the trick. Do a test area before you spend a lot of time because there is the possiblity that it can't be removed.

Thanks sydfloyd44.