Repairing a Scratched Shield

Story by Costa Mouzouris//
December 1 2015

With a little patience, you can save some time and money by easily removing that annoying windshield scratch.

You’ve been putting on the kilometres over the last few seasons, and after many bug-and-grime-removing washes, your windshield is beginning to show its age. Maybe there’s a scratch that’s right in your line of sight that obstructs your view just enough to be annoying. Ideally, if the shield is too scratched to see through clearly, it should be replaced. However, if time restrictions prevent you from replacing it before an upcoming trip, with a little elbow grease you can still improve its clarity, and remove some unsightly scratches to boot.

I don’t usually start with a disclaimer, but in this case I’d like to make a few points quite clear (no pun intended). Repairing a scratched windshield is to be regarded solely as a temporary fix, with eventual shield replacement being the ultimate goal. Also, for demonstration purposes, I used a pair of helmet face shields, as a windshield wasn’t available – any damaged face shield should be replaced with a new one. Also note that most windshields and face shields have a protective hard coating to prevent minor scratches; anything you do to remove scratches will remove this coating, ultimately making the shield prone to scratches.

Removing scratches from a windshield is very much like removing scratches from paint, and you even use the same materials. You’ll need wet sandpaper in 800 and 2000 grits, headlight polishing compound, car wax, an orbital polisher and an ample supply of clean water. You will also need some patience. Very light surface scratches that disappear when the windshield is wet can be removed by polishing with wax, which I’ll describe later. Deeper scratches must first be sanded out.

If you can feel the scratches with your finger, they have gone through the hard coating, and the deeper the scratch is, the larger the area that will be affected by the repair. Begin by washing the windshield thoroughly with soap and water; it must be free of bugs and road grime, or the forthcoming sanding will only introduce more scratches.
Once the windshield has been washed, begin by wet-sanding the scratched area with the 800-grit sandpaper, using small, circular strokes. Use very light pressure: pressing hard might shorten the sanding time, but it will also introduce scuffing that can’t be polished out later. While sanding, frequently wash out the sandpaper in clean water, and rinse the windshield often. If you feel anything grinding about beneath the sandpaper, stop immediately and rinse the sandpaper and windshield. By taking your time and using plenty of water, you’ll effectively remove the scratches while causing minimal damage to the windshield.

Once you’re satisfied that the scratches are gone, which you can confirm with a close visual inspection, switch to the 2000-grit sandpaper to begin the polishing process. The more you sand with this very fine grit sandpaper, the easier it will be to polish the windshield and make it almost as transparent as when it was new. Again, use very light pressure and rinse often while sanding. You can further smooth the repair area repeating this process with 2500-grit sandpaper, but I’ve had good results with just the 2000 grit. When you’re done sanding, the repair area should have a smooth, opaque finish. It’s at this time that you’ll clearly see the outline defining the hardened coating (where you didn’t sand), and the uncoated plastic beneath (the repair area).

The real polishing can now begin, using a product that’s designed to polish clear plastic, like Meguiar’s PlastX headlight-polishing compound. Apply it liberally to the repair area and use the orbital polisher to buff thoroughly. Keep buffing until the polishing compound has dried and is completely gone. Repeat this process about two more times, or until the windshield is almost completely clear.

Use the car wax (I use standard Turtle Wax) with a terry cloth pad on the orbital polisher for the final polishing. Again, apply liberally, and begin by polishing the repair area, then moving on to polish the entire windshield. The more time you spend polishing, the clearer the windshield will be. If you see fine scratches, it will be because you either pressed too hard while sanding or you got some dirt between the sandpaper and the windshield. Remember: Patience is paramount in this process, as well as a very light touch.

Once you’re done, you’ll only be able to see where the hardened coating has been removed when looking very closely at the windshield. Note that this area will scratch and scuff much sooner than where the windshield is hardened, which is why this is a temporary fix.

If you do decide to do this on a helmet face shield, use it only as a temporary spare, for it will not stay clear very long and will especially inhibit vision at night and when it’s raining.

Technical articles are written purely as reference only and your motorcycle may require different procedures. You should be mechanically inclined to carry out your own maintenance and we recommend you contact your mechanic prior to performing any type of work on your bike.

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