Justin,
In one of my former lives, I used to make guards for presses out of Plexiglas.
I find that the stuff is very brittle and it doesn't
take very much force to crack it. We would cut straight sections of it by
scribing and flexing the piece against a table edge. It
would always break in a straight line if properly scribed.
The point is that Spitfires are very flexible and I assume the other Racers are
as well. In extreme situations, I would expect enough
body flex to crack a plexi windshield unless it was mounted with rubber mounts
that will flex instead of transferring the flex to the
plexiglas causing it to crack.
That is why I think sheet vinyl of a thickness in the range od 3/16" might be
the ideal material for this application.
Joe
jmwagner wrote:
>
> On this topic.... and I know there's no one simple answer... as the shape,
> size, configuration, etc. of a windshield is going to make all the
>difference..
> but in general...
>
> What thickness are people using on their TR's? 1/4" 5/16"?
>
> Secondly... I keep hearing about Plexiglass cracking... but overall....
> wouldn't Plexiglass be the better choice? You can polish Plexiglass... Lexan,
> on the other hand, is very unforgiving.
>
> While Plex might crack on an impact, it is unlikely (seems to me) to create
> projectiles.
>
> What I'm getting at is... in the life of a windshield... if the impact is
>hard
> enough to crack the plex... it's likely hard enough to damage lexan...
> meanwhile... if you have lexan... you'll find yourself having to live with
> scratches... during the life of the windshield.
>
> One of the racers mentioned to me, that after losing it in a turn, the car
> became enveloped in dust... and a track helper reached over and whiped down
>his
> windshield, so that he could see before returning to the track..... this
>simple
> wipe down... scratched his Lexan beyond repair.
>
> So the question is... Lexan or Plex? and what thickness are people using?
>
> --Justin
>
> fredd wrote:
>
> > > (Lexan is what they make bullet-proof windows out of, by the way.)
> >
> > Lexan by itself is only used on very cheap low level armored cars, as in
> > money transporters.
> > Even then is has to be very thick, as 3/4" up to 1", and barely will stop a
> > .38spl.
> > So now you know that those very impressive looking Brinks trucks are, only
> > impressive, and their protection level is typical *you get what you pay
> > for*.
> >
> > The only way Lexan is decent in armored glass is when laminated between
> > glass layers.
> > Lexan is good for lamination on the inside of glass to stop smach and grab,
> > as being used in the transit busses in the LA area.
> >
> > BTW, since you guys are thinking about balistic transmission covers and
> > Lexan for your windshield, why don't we build you complete armored race cars
> > ?
> > OK, they would be a bit slower due to the weight :))
> >
> > I have build an armored Countach years ago for one customer.
> >
> > fredd
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