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Lumpy,

As the Technical Manager for ten years of a Pilkington Company producing windscreens, backlights and sidelights for motor vehicles I can say with reasonable surety that all laminated windscreens are fragile and easily cracked by a stone chip. They are only made from two sheets of 1/8" thick glass (maybe even thinner nowadays, as it is 33 years since I moved on from that job) bonded to a vinyl interlay and the crack resistance is no better or worse that an ordinary sheet of 1/8" flat glass hit by a sharp object at substantial speed.

They are built to stick together in an accident when broken and, amongst other purposes, prevent your head breaking through the very tough vinyl interlay. The interlay will deform around your head without tearing, as you probably know because of your profession. As an aside, in early versions of laminated screens the thinner vinyl used in those days did occasionally tear and the head went through the opening in the glass/vinyl until the shoulders hit the screen. The person then fell back into the car after the forward impetus stopped and the glass closed back around the neck, tending to act like a guillotine.
 

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Hard to comment on your reply Lumpy. Don't know why the 1'ers screen should be sub-standard, but that can't be ruled out of course.

Re your impression of stress in the screen. Laminated screens have been produced using toughened sheets of glass, but not usually for normal commuting passenger cars. Anyway, the fact that the crack in your screen started as a chip and ended up 3 months later as a crack halfway across your screen tells me that annealed glass was used for your screen and there should have been no designed stress in it.

However, if the fit wasn't quite correct for the curve of the body opening there would be some, although not very much, stress in the screen due to the forced deformation necessary to fit the screen in the car.

But one thing to bear in mind, for anyone who gets a stone chip in their screen. Body movement, no matter how minimal, will be transfered to the screen and ALL cracks will propogate over time. It is essential to get to a windscreen repair outfit A.S.A.P. and have them repair the chip/small crack. They will drill a small hole at the ends of the crack, which will stop it propogating, and then fill the crack, etc. with a clear sealant.
 

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I took my 1er into RAC windscreens yesterday to get two small chips repaired which happened over Xmas. Neither was terribly big - maybe 2-3mm across and less than 1mm deep. They claim to have repaired them, but both still feel rough to the touch and are just as visible as they were, so I don't think any sealant was used. Are chips like that too small to bother with repairing, or should I go down there and complain?
 

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Probably around Oct/Nov i had a stone chip repaired and it is pretty much invisible now. I would have to go and look really hard to find it. This too was a small chip.

It would probably be worth going back to RAC spl23 and getting them to look at it.
 

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Old Fart, many thanks for the very interesting reply.

Amigo 8)
 

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Personally if I got a chip in my screen I wouldn't get it repaired I would leave it to crack and get the screen replaced. I've have chips repaired in the past and often the repair has looked terrible.
 

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I have to disagree. I have been hit by a stone into the windscreen in my 1er two times and both times the bang from the impact was so loud that I almost shat my pants (good thing I have leather seats :) ). No visible chips though.

Actually it would be nice to get a crack into the windscreen and get a free replacement, two years of usage in quite dusty/muddy conditions have left their wear marks on the windscreen.
 

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ive had a fair few whacks too, had my screen replaced once only... agree with the "****ting of pants" ive had a few of them too!!

Incidently, i can back up Old Farts claims, ive been on site a few times at Pilkington in the uk to film objects hitting glass screens to see the effect...
 

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AdamBMW said:
Personally if I got a chip in my screen I wouldn't get it repaired I would leave it to crack and get the screen replaced. I've have chips repaired in the past and often the repair has looked terrible.
I would be wary about doing that AdamBMW. It is possible that the insurance company could refuse your claim (Having to pay the cost of a replacement when repair is so relatively cheap).

I can't say they would refuse your claim of course, but if left for a few months for the crack to propogate there could be sufficient evidence of dirt in the earlier part of the crack for the insurance assessor to recognise that the initial damage occurred at an earlier date and repairs could have been effected without having to replace the screen.
 

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Hi All,

Well, today on the way home some w*nker in a mini decided to overtake in a turning lane whilst going the opposite way (luckily I wasn't using the turning lane) and fired up a big stone that hit the windscreen. To quote mrash...*******!

Anyway, here is the damage. I would appreciate opinions on what is the best course of action i.e. get it fixed by one of those free windscreen chip removal tents you always see outside Halfords etc...

Opinions/comment much appreciated.


 

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ghibbett, the damage on my windscreen from a lorry passing the opposite direction was worse than this, it was a double chip only just small enough to fit into their resin repair machine.

I would say, get autoglass to come and repair this ASAP before it gets bigger. They hammer it deeper to start with, then put a suction machine over the top which opens the gap. They then inject resin and cure it with ultraviolet light, razor blade off the excess and polish with jewllers rouge. The repair was next to perfect and certainly better than having somebody removing the entire windscreen - AND the insurance company paid for the whole thing without excess or affecting my policy.
 

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Hmm, thanks for that preppeller.
Did you just call Autoglass out or did you do it through the insurance?
 

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I spoke to Direct Line and they gave me the number for autoglass. Auto glass brought along a form so they could claim the money off of my insurance - it was a very simple procedure and I got the impression that thats how it works with all insurers (as it was a generic claim form).
 

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Ghibbett - replacement windscreens are never the same - Autoglass did one for me in a focus and it took 4 attempts to get it fixed and firm without creaking - the first one they put in had a huge scratch down it - why ever they didnt notice it as they began to install I dont know

Anyway 3 screens later the problem was solved - 2 weeks later I traded the focus for a Civic Type R - :lol: :lol: :lol: :lol: all round on that day !!!!!!!

Rotch
 

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Thanks all,

The crack hasn't propagated overnight so will keep an eye on it over the week.

On another entirely more annoying note, I managed to spin the 1'er this morning on a roundabout putting the front bumper up the centre of the roundabout. This was with DTC mode engaged, however I think I hit some diesel.
Net result is a front bumper with ****-loads of scuffs on the underside front lip. Not pleased. However the one saving grace is that it's on the underside of the front lip and unless you get on your hands and knees, you cant see it. Still annoying tho.... :banghead:
 

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Resurrecting an old thread, how big does a chip need to be to bother getting it repaired?

Got pelted by a stone courtesy of a Megane drive on the other side of the road crossing the white line into all the carp gathered in the middle. After the shatting pants noise :D I've now got a line of 3 chips in my line of vision.

Size-wise they're not quite pin-head sized, each about 5-6mm apart. For chips this size on previous cars I've never bothered with repairs and never had a problem, but a combination of it being my newish 1-er and visible it's annoying me.
 
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