Broken Window without a reason

Wow that is strange. Were the pieces on the inside or outside of the car?

 

Might be that there's an "up" travel stop that is supposed to take the load, but it's failed, or loosened, so that the load (of jamming it up as most people do ) when it was last raised was placed on the glass instead of on the intended "up" stop -- just a thought (and why I try to not use stalling the motor as the method for putting a window up on any car)...

Was the window mechanism in the full "up" position?

 

Mods -- How about removing that spam posting (#4). Can't believe cyber-squatters are now showing up here. Kill the bastards.

As for the window, taking Steve's comments a step further, I wonder if something sharp was caught in the track or pushing on the edge of the window, and perhaps the window had been colder when it was closed and then warmed up some and expanded. The side windows on cars are not laminated like the windshield, and are designed to shatter into a million pieces when they break. So if the tension was enough to cause the window to crack, by design it would shatter like that into lots of little pieces. Unusual for a window to go like that, spontaneously. Did the car have a full door frame around the window, or was it a frameless window?

 

All kidding aside - could it have been possibly a neighbor or neighborhood punk with a well aimed BB gun?

The other thought was it was under stress and finally gave, was the car level on all four wheels?

Phil

 

Might thoughts exactly. Probably on-going stress, but mighta been some neighborhood punk, if sight lines allowed for vandalism. Be a bit unlikely for someone to take pot shots through an open garage with the home owner present, but these days, one never knows.

 

This sounds similar to what I'm thinking. Window extra cold and jammed closed with little room for expansion as the window warmed up. Window warms and tries to expand, and finally shatters. Seems pretty weird, though. I'd think most cars have enough slop or give in the mechanism to prevent anything like this.

 

Sometimes these things just can't be explained. My friend who owns an import auto repair shop once came in in the morning and found a Porsche 924, which had been parked inside overnight for safekeeping, in the totally enclosed building, at normal temperatures, with its big rear window shattered in a million pieces. Never found an explanation for that, and I'm sure it was a lot more expensive to replace than a door window.

 

Same thing happened to my wife's Mazda 3 GT.
She came home from work as usual. After dinner I went outside and found the car as shown in the photos. When you look at the photo taken from the side, you can see the back glass looks like it was blown from the inside out. I took it to the Mazda dealer for inspection and they would assume no liability. (just means I was left with the privilege of paying)
I went to the glass shop that replaces all the windshields on my heavy trucks. They found a very, very small chip on the edge of the glass, under the center of the wiper. If you look closely, the fracture pattern originates from that point. Whether or not the chip was caused by a stone or a stress fracture could not be determined. They couldn't explain why the glass seems to have "exploded" from the inside out.
I think it cost about $600.00 CDN all in.
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Maybe when she shut the door the build of pressure inside the cabin was enough to cause the chip to expand.

Phil

 

^^^ That could be from driving it with the busted glass as that area of the car creates a vacuum and could basically be sucking the glass outward after the break.


I've never seen or heard of glass of this type breaking on it's own. I've been a mechanic for Ford, Jaguar, Land Rover and Rolls-Royce, worked as a warranty adjuster for Ford, and now work for an insurance company on it's auto side 16 years experience in the auto world.

The side glass and rear glass in cars are tempered glass and very durable and hard to break. If they do not break during the manufacturing process, or during installation I do not believe they could break on there own.

To help others under stand how strong this glass is a lot of mfg's are using the windshields and rear/quarter fixed glass as structural components in unibody cars.

I would have to say the OP and above have had something cause the glass to break, temp and fluctuations in atmospheric pressure changes are just not plausible to me. Either they were damaged prior to shattering and the temp changes/fluctuations in pressure helped it, or something hit it.

 

How did the window shatter if it had tint on it? If a window is tinted with film and it breaks, the film will generally hold it together so you don't end up with shattered pieces all over.

Tinting windows with film can cause them to break. I had it happen on a skylight once. The film expands and contracts at a different rate than the glass window when it is hot/cold. Since the film is attached to the window directly, this causes stress on the glass and that stress can cause the window to crack.

That all being said, as other posters have stated, a small chip in the glass can cause the whole thing to go quickly. One good example of this is how you can totally shatter a car window by tossing some ceramic at it.

http://www.youtube.com/watch?v=khayfayzXK8

 

On my wife's car it is true that in fact a chip was found on the edge. The resulting fracture emanated from that point. I agree that glass will not crack entirely on it's own.
In our climate here, when it is very cold, I have personally witnessed a crack develop on one side of a windshield always from a small chip, and as the defroster warms the sheet, the crack can go across the windshield in just a few seconds. The problem is that kind of crack is understood and in my case witnessed, but this severe and complete shatter is what I have difficulty with. On my wife's car we did not even hear it happen, and it was not broken when she got home.

 

Tint is a plastic material with a much lower elastic modulus than glass. Consequently tint by itself cannot induce any measureable stress in the glass, and difference in growth would be taken up in the tint. The glass is much thicker and is a stiffer material. It would push the tint around so to speak.

Tint could create heat on the inside surface of the glass if the tint is on the inside and the car was out in the sun and that could cause an issue, but in a closed garage tint isn't going to be related in any way to the breakage. If somebody scratched the glass or nicked it that can cause a stress riser and cause breakage, but the tint didn't do it.

 

I did a search on exploding glass and it looks like it happens on Dinos.
Amazing:

http://www.ferrarichat.com/forum/showthread.php?t=69350&highlight=exploding+glass

 

I came home from a trip one time to find the the inner pane of my dual glazed window in my bathroom had shattered. No explanation. Odd. I replaced it and nothing since.

 

Interesting thread. Do a google search of "bmw exploding sunroofs" and see how many hits you get. It has been discussed forever on BMW forums...with little explanation, and lots of speculation....

 

This has happened to us, exactly the same.

My wife arrived at work in her Land Rover Defender, stopped, and suddenly "bang" the rear window shattered.
Did not fall out of the frame and there was nobody about (it's an Industrial Estate) The window was neither in nor out, just shattered in it's frame. With a gentle push on the glass all the pieces fell out into the back.

It's a flat piece of glass in the rear door of the vehicle. A mystery....can only suggest stress failure, maybe due to temperature change or a fault in the glass.

 

[Cliff Clavin]

"Well you see, Norm, it's like this... A herd of molecules can only move as fast as the slowest molecule and when the glass is shut, it is the slowest and weakest ones at the back that are killed first. This natural selection is good for the glass as a whole, because the general speed and health of the whole glass keeps improving by the regular killing of the weakest members. In much the same way, the human brain can only operate as fast as the slowest brain cells. Now, as we know, excessive drinking of alcohol kills brain cells. But naturally, it attacks the slowest and weakest brain cells first. In this way, regular consumption of beer eliminates the weaker brain cells, making the brain a faster and more efficient machine. And that, Norm, is why you always feel smarter after a few beers."

[/Cliff Clavin]

 

Exploding Glass Objects - Call In Show
http://www.rte.ie/podcasts/2010/pc/pod-v-10111028m44slivelineglass.mp3

 

Many, many years ago, my ex-wife had a Volvo 240 station wagon. The windshield got chipped and started to crack. So I called the insurance company and they sent out a mobile auto glass company to replace it. The guy worked very carefully, got the windshield out, and put the new one in. The Volvo windshield had this wierd set of clips that attached around the windshield to hold the trim in place. The guy got the whole thing done, and was putting the trim on the last clip, gave it a little tap to seat it, and BAM, the new windshield cracks from top to bottom.

After some heavy duty cursing and self-deprication on his part, he removed the broken windshield and installed a second windshield he just happened to have with him. You know what's coming -- he did the SAME THING to the second replacement. Again, on the last clip. Now frustrated and angry as heck, he called his office and they sent another truck out with yet another windshield. The third time was a charm. It went in, no problem, including the molding.

Needless to say, some time later when the molding popped loose, I did NOT try to push it back down. I just left it popped up until I could stop by the window company's office and let them do it.

 

Come to think of it in the late eighties it happened on my 328 rear window under warranty, no explanation I attributed it to the differences in temperature from the heat of the rear engine to the outside cold air.




06 QP sport
06 GS spyder
06 GS coupe
formerly, 1987 328 gts, 1988 328 gts, 1988 328 gtb, 1989 mondial coupe, 1990 348ts


Miss my Ferraris!!!

 

I had the sunroof in my Merc explode at freeway speed. It was horrible. Glass shards came in the car, and blew out backwards scratching the read deck lid. No idea why it happened.