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Author Topic: Bullet Proof Glass..what's that all about ?  (Read 6000 times)

Offline neilep

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Bullet Proof Glass..what's that all about ?
« on: 29/03/2006 16:17:33 »
Greetings Academics whom adorn me with awe !!

Bullet Proof Glass is well tough isn't it !...why ?...what extra special ingredient is there in it ?...Is it manufactured in a process far removed from regular glass ?

Is it very expensive to manufacture and is it as transparent as your car window ?

I ask about the expense of manufacture as it stands to reason that it would make for good strong classes and mirrors and stuff !!




Impact me with your answers, but be gentle..I'm shattered !! ;)

Men are the same as women, just inside out !


 

sharkeyandgeorge

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Re: Bullet Proof Glass..what's that all about ?
« Reply #1 on: 29/03/2006 17:02:45 »
bullet proof glass is made of a series oflayersof toughened glass and polycarbonate laminate (i think its polycarbonate may be wrong) any way when the bullet hits the window the first glass sheet shatters and is caught by the laminate if the bullet still has energy it shatters the next sheet ofgass and so on. the inside is always laminate to prevent flying shards. this is very effective but also very heavey cars with bullet proof glass have to be much stronger with much better suspension plus it expensive to make and can be broken quite easily.

J.B.S Haldane on the perforated eardrums which were a consequence of his pressure experiments "the drum generally heals up; and if a hole remains in it, although one is somewhat deaf, one can blow tobacco smoke out of  the ear in question, which is a social accomplishment".
 

sharkeyandgeorge

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Re: Bullet Proof Glass..what's that all about ?
« Reply #2 on: 29/03/2006 17:04:59 »
oh and yes is just as transparent as normal glass but is normally tinted so the attackers cant see inside

J.B.S Haldane on the perforated eardrums which were a consequence of his pressure experiments "the drum generally heals up; and if a hole remains in it, although one is somewhat deaf, one can blow tobacco smoke out of  the ear in question, which is a social accomplishment".
 

another_someone

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Re: Bullet Proof Glass..what's that all about ?
« Reply #3 on: 29/03/2006 17:07:26 »
In the days before things like polycarbonate, bullet proof glass could be very heavy and very expensive; I'm not sure it is anything as bad as that now.

It is mostly about creating laminates.  In the old days, the laminates would be glasses with different characteristics (the laminates also making it more impervious to cracks travelling through the glass), but now the inner layers would be plastics, which are much lighter.

Polycarbonates are what safety specs and roofs of conservatories are made from.



George
 

Offline neilep

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Re: Bullet Proof Glass..what's that all about ?
« Reply #4 on: 29/03/2006 18:12:39 »
Thank you Chris, Thank you George.

Is it possible then do you think that glass, with the abilities of Bullet Proof glass will eventually filter down to be incorporated into everyday objects, ie: spectacles, mirrors, light bulbs ? glasses ? toys ?? tables ? though I know industrial strength glass is already used for Hi Fi and AV stands...I use one myself with a Tv that weighs over 100kg on it !
 

another_someone

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Re: Bullet Proof Glass..what's that all about ?
« Reply #5 on: 29/03/2006 18:50:15 »
quote:
Originally posted by neilep

Thank you Chris, Thank you George.

Is it possible then do you think that glass, with the abilities of Bullet Proof glass will eventually filter down to be incorporated into everyday objects, ie: spectacles, mirrors, light bulbs ? glasses ? toys ?? tables ? though I know industrial strength glass is already used for Hi Fi and AV stands...I use one myself with a Tv that weighs over 100kg on it !



As I said, safety specs are pretty close to that already (albeit, they do not have a glass surface).

On the other hand, there are definitely cases where bullet proof glass could be a liability (maybe impeding escape, or maybe allowing an excessive build-up of pressure).  What is usually desired is controlled structural failure, not indestructibility.



George
 

ROBERT

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Re: Bullet Proof Glass..what's that all about ?
« Reply #6 on: 30/03/2006 16:43:17 »
Here is an interesting form of bullet "proof" (resistant) glass:-

" We also offer "one-way bullet-resistant glass", designed to stop incoming bullets,
 while giving the person on the inside the option to shoot back.


The glass works by using a brittle glass layer and again, a tough polymer layer. The brittle layer faces outward and shatters if a bullet is fired at it, spreading the force of the bullet over a large area, which is then absorbed by the tough layer behind.

A bullet fired from the other side, however, can puncture the polymer layer easily before breaking the glass, only slowing the bullet slightly. "
http://www.co-opdirect.com/shattersafeglass.html

« Last Edit: 30/03/2006 16:44:32 by ROBERT »
 

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Re: Bullet Proof Glass..what's that all about ?
« Reply #6 on: 30/03/2006 16:43:17 »

 

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