Just like with your paint, tar or rubber and other road grime will aggressively build up and stick to your windscreen. Claying your windshield is the best way to remove buildup of contaminates on glass. The clay will pull out all sorts of stubborn debris that will cause your glass to feel rough and look dirty even after a thorough wash with even the best glass cleaner. The process to clay glass is essentially the same as paint. You’ll need to thoroughly wash and clean your glass first. Then you’ll need to apply a lubricant to the glass and run a small piece of clay bar over the windshield or windows. After cleaning a section of glass with clay use a microfiber cloth to thoroughly remove the clay lubricant. You may want to use a good glass cleaner one last time if the lubricant leaves any haze or streaking. Once done your glass should feel silky smooth and look crystal clear. It’s the ultimate way to ensure that your windshield is absolutely pristine.
When clay barring any surface you need to have a lubricant to allow the clay bar to glide over the surface. There are various liquids that can be used. Don’t make the mistake of using glass cleaner or similar products though. They can break down the clay bar and just cause it to smear across the glass. The best lubricant we can recommend is Chemical Guys Clay Luber. It’s a great choice since it shouldn’t streak and will wipe clean with a microfiber towel.
You don’t need a special clay or lubricant for glass. Regular paint clay and lubricant will work just as well on glass as it will on paint. The only thing you may want to keep in mind is the lubricant. Using a lubricant that will wipe away easily without leaving a residue or streaking. We like the Chemical Guys Clay Luber but you simply use warm water if you prefer. We recommend the Chemical Guys Clay Kit since it includes their lubricant.
Unfortunately no. All a clay bar will do is remove road grime that is stuck to the glass that simply washing won’t remove. You’ll want to use care when clay barring your windshield to ensure you don’t create scratches though. Inspect the clay regularly and fold when contaminants build up on the surface of the clay. Folding the clay will give you a clean surface on the clay itself. If the clay gets too much contamination buildup you may want to get a new piece of clay. If you inadvertently pick up sand grains or other hard bits in the clay you can accidentally scratch the glass if you’re not careful. If you drop the clay on the ground the safest thing to do is use a fresh piece of clay.
A clay bar should be able to remove any surface buildup from glass including hard water spots. Clay bars will remove most contaminates that sit on the surface of the glass. You may need to apply a little extra pressure to remove more stubborn things stuck to the glass. Just be sure the clay is particularly clean when applying extra pressure to ensure that you won’t accidentally scratch the glass.
While you can clay bar the inside of a windshield there really isn’t much need to do so. It would also be very difficult to do without making a significant mess since you’d need to lubricate the surface of the glass. Clay barring the exterior of the glass makes sense because road grime will stick to the surface over time. The inside of the windscreen isn’t usually exposed to contaminants that will stick to the glass that couldn’t be removed with typical glass cleaners. A great glass cleaner that works extremely well without streaking is Stoner’s Invisible Glass. They offer a great Reach & Clean Kit that is ideal for cleaning windscreens and reaching into the difficult to clean areas near the dashboard.
Claying your windshield will leave it silky smooth and much cleaner if you’ve had your car for some time and have never clayed the windscreen. Road grime builds up over time and some adheres so strongly to the glass that washing simply won’t remove it. The only way to truly get it to come off is with a clay bar. Be sure to wash the surface before attempting to clay bar or you’ll be far more likely to end up creating scratches. Use a proper clay bar lubricant so the clay bar will glide across the surface. Work in small areas and wipe away the lubricant as you go. Be sure that your clay bar is clean and fold it regularly to freshen the surface of the clay you’re using. Once you’ve finished claying the entire windshield it should be very smooth to the touch and no longer rough feeling. It should also be much clearer than before.