Q: Are conventional frame style wiper blades going to disappear from windshields?
A. Many late-model vehicles are now being factory equipped with flat or bracketless beam style wiper blades. These have a number of important advantages over conventional wiper blades, yet many new cars and trucks still use the old-style blades. So, although the market is changing, conventional blades should be around for many years to come.
The new frameless or beam-style blades are more complex to manufacture, so they typically cost two to three times as much as the older-style blades. But, they also offer a number of important advantages:
● They conform better to curved windshields. An internal spring molded inside the blade allows it to follow the curvature of the glass as the wiper sweeps across the windshield. By spreading the spring force across the entire length of the blade, the wiper exerts pressure more evenly across the entire length of the blade from end to end. Some blade manufacturers even use different springs for the right and left blades so the blades can conform better to the curvature of the windshield. Older-style conventional wipers typically exert the most pressure at the points where the frame supports the blade. This can lead to uneven wiping and streaking when the blade flexes.
● The new-style blades won’t clog with ice during cold weather, making them suitable for year-round driving. With no frame, there’s no place for ice, snow and sleet to build up. Older style blades can often become clogged with ice, causing them to skip and smear instead of wiping cleanly. Winter blades that have a thin flexible rubber skin over the frame can prevent ice buildup, but that means changing blades when winder arrives, then changing the blades again when spring returns.
● Reduced wind lift and noise. The frame on a traditional wiper creates a lot of turbulence as the speed of the vehicle increases. On a steeply sloped windshield, wind can build up under the frame and lift it away from the glass, causing the blade to skip or streak. To counter wind lift, the frame may have slots to reduce drag and/or spoilers to exert downforce so the blade will remain in firm contact with the glass at higher vehicle speeds. Frameless wipers incorporate a built-in airfoil that exerts just the right amount of pressure to prevent wind lift.
● Longer service life. The painted metal frame on older-style blades can chip or discolor over time, exposing the metal underneath to corrosion. Nobody wants ugly, rusty wipers on their vehicle, so frameless blades are totally sealed against the elements. The synthetic rubber used in many frameless blades is also more resistant to ultraviolet degradation and age hardening, allowing the blade to remain flexible and wipe cleanly for a longer period of time.
Q. How often should wiper blades be changed?
A. As often as necessary to maintain good wet weather visibility. For a motorist in a dry climate, a set of blades might last several years — provided the vehicle isn’t parked outside in direct sunlight for long periods of time. Sun rot can ruin a set of wiper blades in a matter of months in a hot climate like southern Arizona. Dust and grit on the windshield also can be very abrasive to the wiping edge on a set of blades, accelerating wear and the need for replacement.
Most wiper suppliers recommend changing the blades at least once a year to maintain optimum wiping performance and wet weather visibility. Even so, wipers should be replaced regardless of age if they are not wiping cleanly, are streaking or chattering, or are damaged.
