Trimming windshield wiper rubbers yourself - not a good idea!


Suppliers of various tools promise the return of full functioning if you trim back worn wiper blades. However, our experts advise against it!

Windscreen wiper rubbers wear out

Everybody knows that effective functioning of windscreen wiper blades diminishes after a certain time and a certain amount of wear. Streaks and a veil effect start to appear, thus considerably impairing traffic safety. It is especially in the winter months that snow and ice can damage the rubber lips with low temperatures making the material brittle.

The worst-case scenario is that streaks occur as a result of so-called windscreen wiper "chattering". The majority of older wiper blades have completely lost their suppleness and can only rub their way across the windscreen.

How wiper blades have changed in the course of (automotive) history

In the past it was indeed common practice to replace the rubber of the windscreen wipers. In those days, car workshops used to stock yard goods, the wiper rubbers were cut to size and then inserted into the straight metal mounting brackets. Mind you, we are talking here about the 50s and 60s. So in those days with that method, there was no question of trimming blades down.

From a straight to a curved windscreen: the geometry of wiper blades changes

With the introduction of the first panoramic windscreens and laminated safety glass (LSG), more and more curved windscreens were used. And the geometry of the previously inflexible and straight windscreen wipers also underwent a change. Wipers with pressure and claw clips began to appear, wiper blades were adapting to the geometry of the windscreen thanks to the special metal construction.

Wiper blades today: a high-tech product known as the flat blade wiper

For some years now, we have been dealing with high-tech products, a fact of which many consumers and customers may not be aware. It is true that conventional wipers still have a mounting frame with brackets and pressure joints made of metal. However, most modern vehicles today are equipped with the so-called flat blade or flat bar wipers. A spring rail presses the wiper rubber homogeneously onto the windscreen and, as a result of the flat design, the aerodynamics involved have become considerably improved.


Tip: Classic wipers can often be replaced by new flat bar ones.

A special rubber compound, coating and UV protection: lots of wiper blade technology to guarantee a high performance

The actual wiper rubbers consist of a mixture of natural and synthetic rubber, they are graphite-coated and boast UV protection. They perform hard work. In one wiper lifetime, several thousand litres of water are removed from the windscreen and also insects and all kinds of dirt from the street.


Tip: Depending on mileage covered and prevailing weather conditions, our specialists advise you to clean the wiper blades regularly with a damp sponge and some windscreen antifreeze.


In addition, it is advisable to frequently remove remains of insects from the windscreen and not to use the wiper blades as "ice scrapers" in winter. If the wiper performance decreases, the wiper blades have to be replaced. Our experts recommend the following routine: replacement of both wiper blades once a year.

If any wiper blades have ends that have been badly cut - it is better to simply replace them

Some suppliers of cutting tools promote the shortening of old, worn wiper rubbers with special blades. What sounds plausible initially, however, turns out to be difficult and not advisable in practice. Even with these tools the cutting process is not always successful. In order to achieve an absolutely straight and clean cut, skilful dexterity, absolute cleanliness and the right rubber temperature are all decisive. Incorrect course of action will render the wiper immediately unusable and then useless.


Even if shortening is successful, the anti-friction graphite layer is removed, which in turn changes the flexing properties of the wiper lip and also the wiper edge geometry. The wiper then tends to rub, the wiping pattern is not clearly defined. Vehicle owners should therefore also be advised against the use of grinding tools, which are intended to "straighten" the rubber lip and remove dirt but usually only damage it severely.

The road safety of your customers counts!

At the end of the day, the bottom line really is road safety. So it goes without saying that customers should not play around with wiper blades themselves. Only original and high quality products guarantee a perfect wipe pattern. After all, our experts have been researching and developing the optimum bracket construction and a sophisticated and durable rubber compound for years. Whenever necessary, you should definitely advise your customers to have new windscreen wipers fitted.


And no, we don't just advise this because we sell high quality wiper blades, although we are, of course, pleased when one of our products finds favour with your customers. What counts is that you advise them in such a way that they know exactly how to maintain and extend the lifetime of the wiper rubbers with the result that they can enjoy safe driving at all times. By the way: don't forget the rear windscreen wiper!