Wipers Smearing - how to clean car windscreen/wiper blades?

vipa2000

I have a Skoda Octavia with a nightmare screen. I was told Bee Keepers cleaner from Sainsbury's but they no longer stock. I tried Meths - no good. Then found this thread - toothpaste. Absolutely brilliant. Worked within seconds using an old face cloth. So good wife wanted hers doing. Thank you!!!!!!!

bexster1975

Do you mean bar keepers friend?

Bexster

Windowcleaner

Hi All,

I have been trying to sort out my windscreen for several months now and finally cracked it this morning. The problem I had been having wasn't smearing as such, but a kind of reduced visibility for about 3 or 4 seconds after each pass of the wipers, which would then clear up. The outside of the screen had a sort of lace like misty pattern over it after each pass of the wiper blades, and produced an extremely dangerous glare (particularly when driving at night). Obviously in heavy rain, with the wipers passing every few seconds, it was virtually impossible to see what was going on.

I have a background in chemistry, so decided to try to apply my understanding of solubility to dissolve what I considered to be a waxy product that had likely gotten onto the screen from a car wash. I tried everything from ethanol, to mineral spirits but nothing would dissolve the wax that was causing the problem. Then I began to read up on the chemistry of the abrasion resistant waxes used in carwashes (these might also be used in things like rainex too).

Bear with me for the chemistry bit- These waxes get their abrasion resistance by cross-linking the organic wax component with a metal ion- zinc is commonly used in these waxes. During production of these waxes, zinc ions are combined with ammonia and added to the organic wax. When the ammonia evaporates after application, the zinc bonds with the organic wax making it extremely resistant to abrasion and chemically 'locking it in' against the action of organic solvents. In order to break this kind of wax down, you need to remove the metal ion by applying ammonia, and then you need remove the waxy stuff. This is how I did it.

I went to a small local hardware store and bought some household ammonia- hard to get hold of these days in larger DIY stores, perhaps for health and safety or security reasons. I then got some fairy liquid, some cloths, a green scrubby pad, and some newspaper. After putting on some rubber gloves, I applied the ammonia directly to the glass with a cloth (making sure to keep it well away from any rubber or plastic surrounds). After about thirty seconds, I applied some fairy liquid to the scrubby sponge, and gave the window a good scrub. I then removed the soapy residue with lots of scrunched up newspaper. I probably repeated this about three times with a good bit of elbow grease thrown in, and my windows are now smear free. After several months of experimentation, I have finally solved this really dangerous problem.

Few words of warning- ammonia absolutely stinks, and if mixed with certain other chemicals such as bleach, may give off toxic gas. Even without mixing, the fumes from ammonia won't do your lungs any favours so if you are going to do this, do it outside and wear thick gloves. After cleaning the windscreen I also cleaned off the wipers with some fairy liquid and a clean scrubber. This prevented transfer of wax from the wipers back onto the screen. Probably a good idea to wash your car immediately after in case the ammonia has splashed onto other parts of the car, and to be careful how you get rid of the ammonia soaked newspaper and cloths.

Hope other users find this information helpful!