Windscreen secrets for winter
DAMIEN O'CARROLL
Here are few tips on demisting windscreens and removing (or avoiding) frost. Demisting the inside Why does the inside of windscreens fog up? It’s down to the amount of moisture the air can hold.
Warm, high pressure air can hold more water vapour, which is why it gets humid in summer, while cold, low pressure air doesn’t hold as much.
So when you hop in your car on a cold morning, you breath is full of water vapour, but the cold air inside the car can’t hold it all, so it ends up as condensation on the cold glass surfaces
So what is the best way to get rid of it?
Blasting the air conditioning on full heat is the best way to clear it.
Old-time remedies include rubbing half a potato on the inside or cleaning it with shaving foam.. Probably worth a try, particularly if you like the smell of potatoes. Defrosting the outside Pour luke-warm or room temperature over the windscreen to quickly melt off a light frost.
A heavier one may require a bit of scraping with a plastic scraper. Never use a metal one, as it can scratch the glass.
And never use hot water while it will melt the ice quickly, the drastic temperature change could cause your windscreen to crack, making a cold morning even more unpleasant.
Commercial de-icer products are available, but a homemade blend can do just as good a job. A mixture of 2/3 isopropyl alcohol or methylated spirits and 1/3 water with a few drops of dishwashing detergent sprayed on a frozen windscreen will do the trick.
Put an old towel, sack, sheet, or piece of cardboard over the windscreen at night to stop frost forming.
An old remedy that surfaces every year is that a mixture of water and vinegar will stop frost forming if sprayed on the night before.