Does side window tinting give glass laminated strength?

I believe that at some point years ago (60's ?) some cars had
laminated side glass in addition to laminated front windshields
(true?).

Anyways, I'm pretty sure that side window glass in moderm cars is not
laminated (although I'm sure for the extra $15 it would cost it would
sell very well as a safety and theft-prevention feature).

I'm wondering if the application of window tinting on side glass would
give the glass some of the benefits of lamination.

One benefit in particular is that it would take much more effort for
the casual thief to break into a car to steal something.

Anyone ever see the results of a broken window that had tinting
applied to it? Does it hold the glass together if broken the way I'm
thinking it might?

(window films are sold for application on residential and commercial
buildings that are intended to prevent the glass from shattering and
to make it very difficult to break in, so I'm thinking that car window
tinting might be similar).

"Anyways, I'm pretty sure that side window glass in moderm cars is not
laminated (although I'm sure for the extra $15 it would cost it would
sell very well as a safety and theft-prevention feature)."
JS> Some cars offer it.


"I'm wondering if the application of window tinting on side glass would

give the glass some of the benefits of lamination."
JS> Depends on what it is made of. I'm sure this has been thought of
before, because it would be cheaper to make a single sheet of formed
glass rather than shaping and bonding two.

Actually laminated glass is MUCH weaker than the tempered glass that is
used in side and rear glass. It is also MUCH more dangerous than the
tempered glass because it breaks into sharp jagged pieces that will cut
skin very easily.
To answer your question window tinting adds almost NOTHING to tempered
glass other than making it illegal in most states. It does not hold the
tempered glass at all. The security film you have seen sold is MUCH
thicker and works on the untempered glass because it holds the large
pieces together, but even then it is a rip off since it is still real
easy to just push the glass in.
If you really want to stop a thief install some lexan side windows. Just
pray you never get in an accident and are hurt enough that they need to
get you out.
Oh and laminated glass would cost MUCH more than 15.00 more.

--
Steve Williams

"Some Guy" > wrote in message
...
>
> I believe that at some point years ago (60's ?) some cars had
> laminated side glass in addition to laminated front windshields
> (true?).
>
> Anyways, I'm pretty sure that side window glass in moderm cars is not
> laminated (although I'm sure for the extra $15 it would cost it would
> sell very well as a safety and theft-prevention feature).
>
> I'm wondering if the application of window tinting on side glass would
> give the glass some of the benefits of lamination.
>
> One benefit in particular is that it would take much more effort for
> the casual thief to break into a car to steal something.
>
> Anyone ever see the results of a broken window that had tinting
> applied to it? Does it hold the glass together if broken the way I'm
> thinking it might?
>
> (window films are sold for application on residential and commercial
> buildings that are intended to prevent the glass from shattering and
> to make it very difficult to break in, so I'm thinking that car window
> tinting might be similar).
>



----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

On Fri, 13 May 2005, Steve W. wrote:

> Actually laminated glass is MUCH weaker than the tempered glass that is
> used in side and rear glass.

I believe you've got this quite backwards. Everything I've ever read and
heard on the topic -- including from some auto glass company engineers --
contradicts you on this.

DS

Actually it is quite the opposite. Laminated glass is also called
security glass by some manufacturers because it doesn't immediately
shatter into a zillion small pieces. In fact there is still
controversy about whether it is actually safer in side door
applications because there are indications that it actually causes head
and neck injuries because it is so resistant to disassembling.

"Daniel J. Stern" > wrote in message
n.umich.edu...
> On Fri, 13 May 2005, Steve W. wrote:
>
> > Actually laminated glass is MUCH weaker than the tempered glass that is
> > used in side and rear glass.
>
> I believe you've got this quite backwards. Everything I've ever read and
> heard on the topic -- including from some auto glass company engineers --
> contradicts you on this.
>
> DS

Having made windows and windshield as part of business, I say that you have
it backwards.

Chas Hurst

On Sat, 14 May 2005, Chas Hurst wrote:

> > I believe you've got this quite backwards. Everything I've ever read
> > and heard on the topic -- including from some auto glass company
> > engineers -- contradicts you on this.

> Having made windows and windshield as part of business, I say that you
> have it backwards.

Yeah, but you say all *kinds* of stupid ****, Chas.

"Chas Hurst" > wrote in message
...
>
> "Daniel J. Stern" > wrote in message
> n.umich.edu...
>> On Fri, 13 May 2005, Steve W. wrote:
>>
>> > Actually laminated glass is MUCH weaker than the tempered glass that is
>> > used in side and rear glass.
>>
>> I believe you've got this quite backwards. Everything I've ever read and
>> heard on the topic -- including from some auto glass company engineers --
>> contradicts you on this.
>>
>> DS
>
> Having made windows and windshield as part of business, I say that you
> have
> it backwards.
>
> Chas Hurst
>
Guess it depends on what you mean by "weaker". Try this. Find a wreck.
Take a center punch and a small hammer and give a side window (no laminate)
a hit with the center punch sufficiently hard to generate fracture. Do the
same thing with the laminated windshield. Do nothing else. Now, observe
through which opening you will be able to crawl to enter the vehicle.

Non-laminated safety glass is (I believe) tempered or heat-treated to
cause internal stress within the glass to cause it to shatter more or
less completely into small pieces. Now whether or not such tempering
gives the glass some inherent increase in it's capability to withstand
a blunt-force impact is an open question, but irrelavent for the
purpose of this thread because it's what happens after sufficient
force has been applied is what I'm asking about.

If I have an ordinary passenger car side window that has a tint film
applied to it, does the film hold the glass together to the extent
that it would surprise the casual thief or delinquent (surprise that
effortless entry into the car is not possible without some additional
work) hence possibly (or probably) resulting that the thief would move
on to another car? Especially if the thief knows that he must enter
and exit the car through the window (without opening the door - which
would set the alarm off if the car is so equipped) ?

PS: doesn't pre-stressed glass cause distortion when viewed with (or
through) polarized glasses?

FYI: I've heard that "professional" thieves will insert a screwdriver
between the door channel and the edge of the glass (perhaps top edge)
and apply an "in-plane" force to the edge. Apparently tempered glass
is very vulnerable to the application of this kind of force in this
manner, causing it to shatter in a more quiet way than if it was
struck by a hard, sharp object.

Also: I would think that if it's a good idea for the windshield to be
laminated, then the same reasons should hold for side glass. If
something were to strike the side glass sufficiently to break it, I
wouldn't want that same object to be able to effortlessly continue on
and hit me in the head. Also, once a window is broken, it essentially
disappears and gives the occupant no protection from the intrusion of
other objects, as well as giving no barrier that would prevent the
occupant's head, arm, etc, from being thrown out the open window and
into harms way.

Is the sole reason for not laminating the side glass is to allow
emergency rescue personel to access the interior by breaking a window
(which could be accomplished by not laminating the rear side
windows)? If that is indeed the reason why side glass is not
laminated, it seems to be a pretty weak reason, and it's confounded by
the illogicality of the elimination of the old-fashioned door handles
in preference to the recessed plastic handles we have today (the old
side handles of the 60's allowed rescue personel something to grab or
hook onto to pull the door open if necessary - modern handles don't
allow this).

"Some Guy" > wrote in message ...
>
> Non-laminated safety glass is (I believe) tempered or heat-treated to
> cause internal stress within the glass to cause it to shatter more or
> less completely into small pieces.
>
Essentially correct/ There's chemical tempering and heat tempering. IIRC
both result in residual compressive stresses at the surface.
> If I have an ordinary passenger car side window that has a tint film
> applied to it, does the film hold the glass together

Not to any great extent, certainly not to the extent afforded by the organic
interlayer in a laminated windshield
>
> PS: doesn't pre-stressed glass cause distortion when viewed with (or
> through) polarized glasses?
>
> FYI: I've heard that "professional" thieves will insert a screwdriver
> between the door channel and the edge of the glass (perhaps top edge)
> and apply an "in-plane" force to the edge. Apparently tempered glass
> is very vulnerable to the application of this kind of force in this
> manner, causing it to shatter in a more quiet way than if it was
> struck by a hard, sharp object.

Perhaps they do. Whatever force is applied, it still has to result in a
localized fracture of some nature--just like in the old B movies when the
bad guy broke the window with a hammer wrapped in a towel.

> Also: I would think that if it's a good idea for the windshield to be
> laminated, then the same reasons should hold for side glass. If
> something were to strike the side glass sufficiently to break it, I
> wouldn't want that same object to be able to effortlessly continue on
> and hit me in the head. Also, once a window is broken, it essentially
> disappears and gives the occupant no protection from the intrusion of
> other objects, as well as giving no barrier that would prevent the
> occupant's head, arm, etc, from being thrown out the open window and
> into harms way.
>
> Is the sole reason for not laminating the side glass is to allow
> emergency rescue personel to access the interior by breaking a window
> (which could be accomplished by not laminating the rear side
> windows)? If that is indeed the reason why side glass is not
> laminated, it seems to be a pretty weak reason, and it's confounded by

Aren't you over analyzing this? Vehicles travel forward. Laminated
windshields are effective in preventing a degree of passenger compartment
intrusion of some objects. Side windows and backlights keep out the rain.
They also cost less to manufacture in tempered safery glass than in
laminated glass. See my previous post about use of a centre punch.

Google the FMVSS and read about windshield retention and other requirements
covering automotive glazing.

> the illogicality of the elimination of the old-fashioned door handles
> in preference to the recessed plastic handles we have today (the old
> side handles of the 60's allowed rescue personel something to grab or
> hook onto to pull the door open if necessary - modern handles don't
> allow this).

The same way they don't allow unlocking in a rollover accident the way
pushbuttons used to.