Q: Can Damaged Wiper Blades Scratch My Windshield?

The short answer is yes. There are two types of wiper blades on the market today. One is definitely more prone to damaging your window than the other if the blade should become damaged.

The soft rubber that floats over your windshield is designed to work like a squeegee. In order for this rubber to maintain its shape it relies on a frame. Without it, the rubber peice of the wiper blade is not much more rigid than a rope. It would simply fold and tangle as soon as the wipers were turned on. There are generally two types of wiper blades on the market today. Their design differs mainly with the frame design. The older design utilizes a metal frame while the newer design uses a simpler plastic frame.

The Older Frame Design

The older design is a metal frame structure that holds the rubber portion of the blade at eight points. There may be less points of contact depending on the length of the blade. This design tends to sit higher off of the windshield giving it a tendency to grab the wind. On performance vehicles traveling at higher speeds, this can cause problems. The rubber squeegee held by the frame has two pieces of metal strips to add to its rigidity. Without these two strips of metal, the rubber could not hold its shape.

Some like this design because rubber refills can be used, although this becoming less common. The main problem with using refills is the intricate metal frame structure becomes loose over time and the blade will not work as effectively as when it was new. Refills are a cheaper option if cost is an issue, although as cost comes down on newer designs, the industry is steering away from using refills.

Newer Beam Style Blade

Modern manufacturing techniques have made many things possible that weren’t in the past, and this is one of those products. The newer beam style wiper blade has many benefits the older metal frame style does not. The rubber squeegee portion of the blades are the same material, but that is where their similarities end.

A beam style blade is much less likely to scratch a windshield if it were to be damaged. There aren’t any metal components involved and the plastic used is much softer than metal. The rubber squeegee is an integrated part of the frame providing infinite points of contact to give the rubber that contacts the windshield superior support. Beam style blades sit lower on the windshield and have a wind effect that forces them onto the windshield opposed to lifting them off. More expensive forms of the beam blade are designed to increase windshield pressures at freeway speeds and have several articulation points for windshields that have more curve to them.

Conclusion

As stated in the beginning, a damaged wiper blade can and often does scratch a windshield. The older frame designs are much more prone to this problem, in part due to their extended use when the owner opts to install refills. The refills themselves, which are most often the first point of failure, contain hard metal that can scratch a windshield.

The newer beam style blades found on most newer cars are much less likely to scratch your windshield if they themselves are damaged. This is mainly due to the softer plastic used to build them and lack of metal used in their construction. Even so, if these blades are damaged and not replaced soon, the plastic can scratch a windshield if the owner continues to use them. Some manufactures may choose to imbed other materials inside the beam frame to further their rigidity. If the blade is damaged enough, these material could be exposed to your windshield and scratch it.

There is one scenario that will definitely scratch your windshield that affects both style blades the same. If the wiper blade is damaged enough that it falls off, the wiper arm that holds the blade will contact your windshield. The wiper arm is made of very hard steel that will definitely scratch your glass. In the event of total wiper blade failure, the wipers should not be used or a windshield scratch will occur.

In conclusion, the best course of action is to keep your wiper blades in good condition. Relative to the price of your windshield and your safety, they are a very cheap investment that provides you with the ability to see while driving. If you’re concerned that your wipers may be damaged, feel free to contact a certified mechanic who can replace your wiper blades at your own convenience.