[Patgaepx]

Can rust affect the surface of glass beyond cosmetic staining?

I have recently had a 10mm safety glass shower screen explode into small pieces, I was at home at the time and it sounded like a gun going off.

There was no-one in the bathroom, no breeze going through the house, no noise (vibration) from a stereo or tv, and the day was a very mild one with little change in temperature. It would be amongst the most stable conditions the screen has experience in the time since it was installed, then.. KABOOM.

The reason I ask about rust is that, in cleaning up, I noticed one screw holding the base mount down was rusted. The rust had spread to the glass and had stained at least one of the pieces I found, I am wondering if the rust could have affected the surface of the safety glass enough to cause the explosion?

I have in the past noticed materials that can't themselves rust getting pitted by rusty items so I was wondering about that possibility in this case.

One other thing I noticed was that there were a lot of small, very fine, slithers and shavings of glass to be cleaned up, a lot more than my only other previous experience with shattered safety glass which was a broken car windscreen going back a fair few years, can this be an indication of poor manufacture?

[usaguedriedax]

Maybe it wasn't rust but instead it was nanothermite planted to eliminate you whilst bathing because you know too much?

[moopogyOvenny]

Can rust affect the surface of glass beyond cosmetic staining?

I have recently had a 10mm safety glass shower screen explode into small pieces, I was at home at the time and it sounded like a gun going off.

There was no-one in the bathroom, no breeze going through the house, no noise (vibration) from a stereo or tv, and the day was a very mild one with little change in temperature. It would be amongst the most stable conditions the screen has experience in the time since it was installed, then.. KABOOM.

The reason I ask about rust is that, in cleaning up, I noticed one screw holding the base mount down was rusted. The rust had spread to the glass and had stained at least one of the pieces I found, I am wondering if the rust could have affected the surface of the safety glass enough to cause the explosion?

I have in the past noticed materials that can't themselves rust getting pitted by rusty items so I was wondering about that possibility in this case.

One other thing I noticed was that there were a lot of small, very fine, slithers and shavings of glass to be cleaned up, a lot more than my only other previous experience with shattered safety glass which was a broken car windscreen going back a fair few years, can this be an indication of poor manufacture?

So many questions when the answers are probably simple. Rusty screw means that there is a weak point, which if dry would mean a loose joint.. glass would fall out rather than explode.. but if rust indicates water in frame.. then expansion of frame will put undue pressure upon the glass.

[Patgaepx]

So many questions when the answers are probably simple. Rusty screw means that there is a weak point, which if dry would mean a loose joint.. glass would fall out rather than explode.. but if rust indicates water in frame.. then expansion of frame will put undue pressure upon the glass.

It's a frameless screen. The glass was secure with three mounts and is siliconed all round (on the two edges), even the rusty screw was still doing it's job and in that mount there were 2 screws, only one of which was rusty.

A few days ago the screen was washed and it always moves a reasonable amount when cleaned but doesn't explode, there was 2 hot showers had in that morning and it didn't explode with the temperature changes... but then in the arvo when there is no stress on it at all... KABOOM.

[broksaksaak]

toughened glass can do exactly what you have described. it has something to do with the way it is made and internal stresses that are inherent in the manufacturing process. a slight scratch can lead to catastrophic failure. the rusty fixing may have placed undue pressure at one location. bit like how rusty reo in concrete can blow bits of the surface out, concrete cancer i think it is called.

[usaguedriedax]

If we discount the fact that someone might be out to get you, you might have had a case of:

"Spontaneous glass breakage"

http://en.wikipedia.org/wiki/Spontaneous_glass_breakage

[Patgaepx]

toughened glass can do exactly what you have described. it has something to do with the way it is made and internal stresses that are inherent in the manufacturing process. a slight scratch can lead to catastrophic failure. the rusty fixing may have placed undue pressure at one location. bit like how rusty reo in concrete can blow bits of the surface out, concrete cancer i think it is called.

I understand there could be any number of reasons for it, but what I am interested in is whether or not rust can affect the surface of glass, can it 'pit' it?

I really don't think it is likely to be from expansion of the screw as it rusts because the screw was countersunk and had some expansion room within the countersunk area. I also think it would be odd if the cause was expansion and contraction of the glass as in the link supplied by furious because it exploded at a very stable time, and just hours earlier it was subjected to hot showers, if there was a defect that was a ticking time bomb I would have thought that hot showers after a cold night would have triggered it.

I know it will never be known what caused this, but I am interested in whether it is even a possibility that rust could undermine the surface of safety glass, or is the only effect rust can have on glass cosmetic?

[broksaksaak]

but what I am interested in is whether or not rust can affect the surface of glass, can it 'pit' it? can't help with that bit.

[moopogyOvenny]

I know you want it to be but sometimes the effect isn't enough to be more than negligible. From memory, I've seen a lot of stained glass and even done quite a bit of work with glass. The guy across the road used toughened glass doors and windows from shopfronts to make enclosures in his yard for turtles and lizards.. several of them just shattered. somtimes by the slightest touch, others just for no apparent reason.

Perhaps what I'm trying to say is that no, I haven't observed rust cause windows to shatter. Rust may interfere with coatings on glass but not to my knowledge, the glass itself.

[CHyLmxDr]

I understand there could be any number of reasons for it, but what I am interested in is whether or not rust can affect the surface of glass, can it 'pit' it?

I really don't think it is likely to be from expansion of the screw as it rusts because the screw was countersunk and had some expansion room within the countersunk area. I also think it would be odd if the cause was expansion and contraction of the glass as in the link supplied by furious because it exploded at a very stable time, and just hours earlier it was subjected to hot showers, if there was a defect that was a ticking time bomb I would have thought that hot showers after a cold night would have triggered it.

I know it will never be known what caused this, but I am interested in whether it is even a possibility that rust could undermine the surface of safety glass, or is the only effect rust can have on glass cosmetic?

Glass is pretty resistant to chemicals. About the only two things I know of that can significantly etch into glass are hydrofluoric acid and strong caustics. But the caustics are pretty slow at it.

[Kimeoffessyr]

Can rust affect the surface of glass beyond cosmetic staining?

I have recently had a 10mm safety glass shower screen explode into small pieces, I was at home at the time and it sounded like a gun going off.

There was no-one in the bathroom, no breeze going through the house, no noise (vibration) from a stereo or tv, and the day was a very mild one with little change in temperature. It would be amongst the most stable conditions the screen has experience in the time since it was installed, then.. KABOOM.

I dont know about it being that loud But your temp , vibs , breeze wont make 10mm toughened pop.

The reason I ask about rust is that, in cleaning up, I noticed one screw holding the base mount down was rusted. The rust had spread to the glass and had stained at least one of the pieces I found, I am wondering if the rust could have affected the surface of the safety glass enough to cause the explosion?

I have in the past noticed materials that can't themselves rust getting pitted by rusty items so I was wondering about that possibility in this case.

A little semi circular clamp about 40mm long 20 high? Yeah they come with a zinc plated locating screw that you shouldn't use but the rust on the glass wont make it blow, in an extreme case when a screw rusts it expands but those screws are too small and it has other places to go.[/QUOTE]

One other thing I noticed was that there were a lot of small, very fine, slithers and shavings of glass to be cleaned up, a lot more than my only other previous experience with shattered safety glass which was a broken car windscreen going back a fair few years, can this be an indication of poor manufacture?

No those pieces come off along the polished edge , actually a poorly or incorrectly toughened sheet will have big pieces .

10mm can blow spontaneously but it is exceptionally rare, the most common causes are a "seed" or inclusion in the glass (usually only found in cheap imported shite), a Nickel sulphide crystal growing also (again rare).
Most of the time it is rubbing on a screw head , the wall/floor has moved or has been at some time prior to install been placed on concrete. If it was a really bad install and it was off the floor and the wall fixing gave out it can rotate out of the channel and the corner can hit the tiles.

Brett

[oemcheapdownload]

Installation damageWhile glass is being moved and installed, it is easy for the glaziers to nick or chip the edges of the glass with various tools. It is also possible for fasteners such as nails or screws which are used to attach glass stops to nick the glass edges if these fasteners are installed at an improper angle. These small nicks or chips may not result in immediate breakage. However, over time, as the glass expands and contracts, stress concentrations can develop around the nick that break the entire unit. In the case of tempered glass the entire unit usually breaks.

In ter est in g.

[PickEmUp]

10mm can blow spontaneously but it is exceptionally rare, the most common causes are a "seed" or inclusion in the glass (usually only found in cheap imported shite), a Nickel sulphide crystal growing also (again rare).
Most of the time it is rubbing on a screw head , the wall/floor has moved or has been at some time prior to install been placed on concrete. If it was a really bad install and it was off the floor and the wall fixing gave out it can rotate out of the channel and the corner can hit the tiles.

Brett

Thanks for that explanation; the same happened here a year or so ago. and yes, it was a very loud 'gunshot' sound and bits of glass went everywhere and even 'ricocheted' well out of the bathroom.
I was outside and was glad I had been.
I never understood how it was or could have been caused.

[moopogyOvenny]

Thanks for that explanation; the same happened here a year or so ago. and yes, it was a very loud 'gunshot' sound and bits of glass went everywhere and even 'ricocheted' well out of the bathroom.
I was outside and was glad I had been.
I never understood how it was or could have been caused.

Glass is interesting stuff which I am sure we have discussed on many levels before.

One day which happened to be my son's fourth birthday when we had just moved into this house newly built. We were doing lego train set on floor when..
The front yard was empty, because the builders had needed the space. A willy willy hit. A big one.. I sat immobilized the windows bulged. they were just about to snap and spray, when they snapped back to reality plane and just quivered. The room was suddenly full of dust.

[Kimeoffessyr]

In the case of tempered glass the entire unit usually breaks.

Made me smile
( hard to break half a sheet )
PS Tempered is a Yanky term we use Toughened over here.

[oneliRafmeene]

We had a glass oven dish explode.
It had been used a few times in the microwave with no ill effects.
This time it was drying on the draining board when it went off with a gunshot like sound. It shattered into 100s of pieces.
We sent a photo to the manufacturer who said they'd never had it happen before. They sent us a replacement + some freebies.

[maks_holi]

We had a glass oven dish explode.

Me too- but it was resting on a hotplate that was accidentally left on. Whoops. We were finding glass throughout the kitchen for weeks afterward.