Getting sap/wax off windscreen?

[Martin]

Have you tried rain-x on it after cleaning. It repels the water and makes driving in rain much better. I rarely even use my wipers.

I've also had the same results from Rain-X (have to apply it correctly but) - it's pretty cool

I'm currently trying Nanolex glass sealant to see if that gives better results

If you have any decent paint sealant (or even wax) you should be able to blast small tree sap spots off the car
with the high pressure hose at a self serve car wash (as long as it's fresh, within the last 5 days)
If I don't get a good spot at work I have to park under trees that leave little white spots of sap
These sap spots are very sticky and if I touch them they smear
My car is currently protected by AutoGlym Hardwax
I can blast the sap off with the high pressure soap spray

Large blobs of tree sap need to be dissolved first - various products can help - Einszett 1Z Tree Sap Remover

[Tweeked]

Boiling water will not crack your windscreen......................
I have a glass mug for my tea/cofee and it has never cracked.

I preface this by saying you have to be within reason though (i.e. not at -10 degrees) however by the time the water boils and you actually get it to the car it will be more like 75 degrees not 100.

Winter Driving Tips - Hot Water Myth - YouTube

Thermal shock will crack a damage windscreen, ie chipped, or cracked.... but you can do it if you like.

[team_v]

Winter Driving Tips - Hot Water Myth - YouTube

Thermal shock will crack a damage windscreen, ie chipped, or cracked.... but you can do it if you like.

I have done it on all my cars and the family's cars as well when they have sap and it has never caused an issue.

[Tweeked]

I have done it on all my cars and the family's cars as well when they have sap and it has never caused an issue.

Even cold tap water on a hot windscreen (which has been in the sun) will crack if there is an imperfection in the surface tention of the glass.

Google Answers: cracks in car windshield from car wash

Your glass mug will be tempered to take the thermal shock but it will have a limit... in saying that if you took the glass from the fridge or freezer then added hot water it to would shatter.

[Martin]

Not at all

When I was eight years old it was my job to take the kettle out to the car (just boiled) and pour it over dad's front and rear windows in -8 degree frosts - did this for years, never had a problem

zone toughened glass is very strong - even with chips in it
It's physically and thermally stronger than regular glass

Sudden impact, especially from something sharp, that's what will damage a windscreen

[team_v]

Not at all

When I was eight years old it was my job to take the kettle out to the car (just boiled) and pour it over dad's front and rear windows in -8 degree frosts - did this for years, never had a problem

zone toughened glass is very strong - even with chips in it
It's physically and thermally stronger than regular glass

Sudden impact, especially from something sharp, that's what will damage a windscreen

Thank you for proving my point.
Until people have actually done it then they can't comment on "damage that it will cause."

This also isn't a new glass technology as i have done it to my 24 year old corolla.

[Martin]

This also isn't a new glass technology as i have done it to my 24 year old corolla.

Also note, I was 8 years old all of 42 years ago, definately not new glass technology

[Guest001]

Not at all

When I was eight years old it was my job to take the kettle out to the car (just boiled) and pour it over dad's front and rear windows in -8 degree frosts - did this for years, never had a problem

zone toughened glass is very strong - even with chips in it
It's physically and thermally stronger than regular glass

Sudden impact, especially from something sharp, that's what will damage a windscreen

In actual fact that is the wrong thing to do because hot water freezes faster than cold water

Proof of it here BBC - Richard Angwin's weather - the Mpemba effect

Strange but true. I proved it lots of times as I lived in a cold climate with 25 Degree frosts.

Put warm water on the screen and it almost immediately froze Put cold water on and it took much longer to start to freeze.

Has been scientifically proved to be true.

On a nature program recently it was proved by going outside in sub freezing temps in Alaska

The guy threw a jug of cold water up in the air and it fell to the ground as water before freezing on the ground.

He then threw a jug of hot water up in the air and it froze immediately and fell to the ground as snow.

FACT

Best way to clear screen is to scrape frost off with a credit card and turn demist on cool for a few minutes

[Martin]

More pointless internet theory
(we were actually discussing the question "would hot water on a cold windscreen cause damage or cracking")

In the real world we were not trying to freeze water in the shortest time frame

The hot water does melt the ice very quickly - that's what we wanted
Yes, the hot water will also freeze fairly quickly - if you leave it on the windscreen
(we don't live in a -25 degree climate where hot water will freeze instantly)
You just the wipers a few times and then a quick wipe off with a cloth
Additionally have the windscreen demister running
It works just fine...

[Guest001]

More pointless internet theory
(we were actually discussing the question "would hot water on a cold windscreen cause damage or cracking")

In the real world we were not trying to freeze water in the shortest time frame

The hot water does melt the ice very quickly - that's what we wanted
Yes, the hot water will also freeze fairly quickly - if you leave it on the windscreen
(we don't live in a -25 degree climate where hot water will freeze instantly)
You just the wipers a few times and then a quick wipe off with a cloth
Additionally have the windscreen demister running
It works just fine...

Is not pointless theory is a scientific fact. Whether it works for you or not I dont care. I always used cold water and turned the wipers on. My old man would have killed me if I put hot water on a frozen screen but obviously he didnt know what he was talking about.

Only was a milkman who had this problem every winter for nearly 30 years and never cracked a screen.

[Swainey32]

who gives a f, the man just wants to remove sap from he's windscreen, we covered it.

Hot water melts ice, correct
Windscreens are strong, correct
Hot water plus cold windscreen with already existing cracks cause it to break, correct
The idiot that poured hot water on a cracked windscreen most definitely deserved the repercussions

Cased closed, moving on to productive things now

[Tubbs76]

Coming from a detailing background, if it sap as in soft, simply wash the winscreen as required with hot soapy water. If it is thick as in has dried, wet windscreen and use a qood quality razor to scratch off. it may take u numerous attempts to get it perfect but really the only way to do it.
Ive see ninstances where the sap is so bad we had to replace windscreens.
Best advice, dont park it under the tree thats leaking sap....

[Martin]

who gives a f, the man just wants to remove sap from he's windscreen, we covered it.

Cased closed, moving on to productive things now

Well said

[larsie]

Just an update. I got around to polishing my windscreen again with much better results. I wouldn't say the windscreen is as good as new (as there are quite a few very small stone chips) but all streaking is now gone and I can actually see properly when it's raining!