Bulletproof Materials:Lexan/Kevlar
Christopher J. Rasmus
The prime materials used in the construction of these vests are kevlar and
steel inserts, I believe. One police friend of mine told me that, after
accidently tearing a portion of his vest, he saw that the thing was actually
made of between 18-21 layers of kevlar cloth approximately 1 inch thick.
Dupont makes kevlar fibers. I've ordered a brochure from them about their
product, so if anyone wants to know what I find out...email me.
Then there's lexan. Made by General Electric, this polycarbonate 'glass'
(actually more like plexiglass) has extremely good impact-absorbing
characteristics, even at sub-zero temperatures. I found out about it's
ballistic-resistance while taking an architecture course at the local
community college. The construction industry uses it to make, among
other things I suppose, shower doors. Its naturally clear, and can be
made opaque by coloring. Finally, it's 'cold-formable' (at least in
small thicknesses), and can be pressed into the desired shape at the site.
I've also ordered a brochure from GE, so ditto the above.
Now I'm not an expert on the above materials, but I was wondering what
kind of armor could be made combining the two. I've seen a reference in
an Encyclopedia of Technology in my school's library that (paraphrased)
"Polycarbonates are used to make ..., ..., and battle armor for
soldiers." I've also heard (from local glass suppliers) that 1/4 inch Lexan
resists (they make the distinction between being bullet 'proof' and bullet
'resistant'-Lexan is the latter) up to .22 calibre bullets. 3/8 inch up to
.38, and they didn't know for anything higher-they're supposed to be
getting back with me. I would assume (possibly erroneously) that 1/2 inch
Lexan may resist up to .45 calibre bullets.
My main desire comes from wanting to have some kind of body armor that
provides more than the upper-torso/chest protection that the modern Kevlar
vests give. Full body armor, covering all major areas of the body except
the joints to preserve mobility. It is my belief (from all the info I've
divulged above) that such a suit, combining possibly 15-20 layers of
Kevlar sandwiched between two 1/4 inch layers of Lexan, would give good
over-all ballistic protection perhaps superior to that of Kevlar vests
with steel inserts with the advantage of less weight. Also, a helmet
constructed of maybe a 1/2 inch cylindrical shaped clear-Lexan 'dome'
would be the ideal head protection (again, possibly). Finally, the
simplest protection could be gained from the forming of some kind of
curved, clear shield made from some thickness of Lexan, and possibly some
very superior shield protection could be gained with loss of clearness by
incorporating layers of Kevlar in between the Lexan. *shrug*
All of the above is to ask this: What do the rest of you think? I'm being
realistic:I don't have all the info (the brochures are on the way) and
when I in fact receive it, I might have to scrap the idea completely. It
might weight too much, or it might not provide enough ballistic
protection, etc.
Thanks for your time,
Chris
Jesus is the Lord of Lords and the King of Kings and He's coming back SOON!
Eric A. Schwartz
Christopher J. Rasmus <cra...@mailer.fsu.edu> wrote:
Re: Kevlar/Lexguard body armor.
Lexguard (the laminated composite Lexan used as armor) is too
bulky for use as body armor, IMO. While light weight,
you're talking about a panel several inches thick. Its
main application, as you found, was in stationary armor
for buildings. Even armored limousine manufacturers prefer
a glass/plastic composite, because Lexan would be too thick
to form into windshields or windows. It might be useful in
the faceplate of a helmet, however.
SpectraShield polyethylene is stronger than Kevlar, and is
used in many newer types of body armor. It lacks Kevlar's
heat resistance, however.
For thin, lightweight, rigid armor, a carbon fiber composite
might be best. Israeali 'toga' armor for the M113 APC
is carbon fiber, and the thin panels of it are said to
be able to stop a .50BMG before it even its the APC's metal
armor. That might be best for plate reinforcements over
the chest area, and for the helmet, though it is quite
expensive and hard to work with, and only works best in flat
layers. On the other hand, an angular, faceted helmet would
be a rather intimidating and effective unit, especially if
you designed it so the slopes of the facets help to reflect
bullets off to the side or top.
E.S.
David Ballard
: My main desire comes from wanting to have some kind of body armor that
: provides more than the upper-torso/chest protection that the modern Kevlar
: vests give.
Make sure it's legal to wear body armor where you live. Here in Virginia
it's either a Class 3 or Class 1 Misdemeanor (I can't remember which) to
wear body armor.
: Jesus is the Lord of Lords and the King of Kings and He's coming back SOON!
Amen!
______________________________________________________________________
David Ballard | "We are shaped and fashioned
dav...@beacon.regent.edu | by what we love." - Goethe
Mike Chapman
David Ballard <dbal...@pinn.net> wrote:
#Christopher J. Rasmus (cra...@mailer.fsu.edu) wrote:
#
#: My main desire comes from wanting to have some kind of body armor that
#: provides more than the upper-torso/chest protection that the modern Kevlar
#: vests give.
#
#Make sure it's legal to wear body armor where you live. Here in Virginia
#it's either a Class 3 or Class 1 Misdemeanor (I can't remember which) to
#wear body armor.
How can I say this politely.... uhm, fuck that. Here's my advise -
everyone wear body armor on the OUTSIDE and carry their pistols
in a holster. I can't believe that it's illegal and further that
you would be advising people not to break such a law. The right
of self defense is supreme over any law and any government, PERIOD.
#: Jesus is the Lord of Lords and the King of Kings and He's coming back SOON!
#
#Amen!
Yeah, whatever. Something's coming soon and if you spend your
time looking for Jesus you're going to miss it.
--
mi...@chimera.med.virginia.edu | mike%do...@virginia.edu
Citizen Chapman
Dillon Pyron
Much about armouring deleted.
The only problem with this design is that it has already been tried. In the
Middle Ages. You have essentially designed a modern suit of armour, complete
with the traditional problems. The advantage that soft armour gives is full
motion. There is no way to provide for full motion and still have a rigid (Lexan
in this case) torso. And jointing it just leaves little gaps for the inevitable
"lucky shot" (which seems to occur more often than it should).
OTOH, I have recently finished an SF novel involving this concept. It worked
perfectly, there. :-)
I guess great minds think alike :-)
Dillon Pyron
PADI AI-54909 USPSA A-26031
Robert B. Murray
: On the other hand, an angular, faceted helmet would
: be a rather intimidating and effective unit, especially if
: you designed it so the slopes of the facets help to reflect
: bullets off to the side or top.
And may the force be with you, Luke.
Dale
c/o rbmu...@netcom.com
-----------------------
Don't tread on me.
Julius Chang
#
[stuff deleted]
#the joints to preserve mobility. It is my belief (from all the info I've
#divulged above) that such a suit, combining possibly 15-20 layers of
#Kevlar sandwiched between two 1/4 inch layers of Lexan, would give good
I guess that you don't care much about comfort, concealability.
or weight. I hope you don't live in a warm climate and that
you don't sit down much during the day while you wear that
contraption.
#over-all ballistic protection perhaps superior to that of Kevlar vests
#with steel inserts with the advantage of less weight. Also, a helmet
#constructed of maybe a 1/2 inch cylindrical shaped clear-Lexan 'dome'
#would be the ideal head protection (again, possibly). Finally, the
I guess you'll need the helmet since the bad guys will
clearly spot your body armor and thus go for a head shot.
Why not just sew together a bunch of used Kevlar-belted
tires?
-Julius
Peter Prun
jch...@whidbey.net (Julius Chang) wrote:
cra...@mailer.fsu.edu (Christopher J. Rasmus) wrote:
#>over-all ballistic protection perhaps superior to that of Kevlar vests
#>with steel inserts with the advantage of less weight. Also, a helmet
#>constructed of maybe a 1/2 inch cylindrical shaped clear-Lexan 'dome'
#>would be the ideal head protection (again, possibly). Finally, the
#
#I guess you'll need the helmet since the bad guys will
#clearly spot your body armor and thus go for a head shot.
#Why not just sew together a bunch of used Kevlar-belted tires?
*That's* why the Michelin Man wears those tires! He's concerned about
being shot! :-) :-)
Pete
Michael Knape
##Make sure it's legal to wear body armor where you live. Here in Virginia
##it's either a Class 3 or Class 1 Misdemeanor (I can't remember which) to
##wear body armor.
#
#How can I say this politely.... uhm, fuck that. Here's my advise -
#everyone wear body armor on the OUTSIDE and carry their pistols
#in a holster. I can't believe that it's illegal and further that
#you would be advising people not to break such a law. The right
#of self defense is supreme over any law and any government, PERIOD.
#
How can this be true? If it is true, you have no obligation to
abide by a law of this type under our constitution. If you can
legally buy it you can legally wear it.
Gary Coffman
# Why not just sew together a bunch of used Kevlar-belted
# tires?
Ah, the Michelin Man look. :-)
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | emory!kd4nc!ke4zv!gary
534 Shannon Way | Guaranteed! | ga...@ke4zv.atl.ga.us
Lawrenceville, GA 30244 | |
David A. Honig
#I know they make bulletproof vests/flak jackets for the police/military.
#The prime materials used in the construction of these vests are kevlar and
Sounds like plates or laminates of the plastics might be good material
to hang on door panels when driving through LA.... A bit much for
restaurant-wear however.
--
David A. Honig
"If Nicole Simpson owned a gun, she might be a wealthy widow instead..."
-paraphrasing Jeff Cooper
Aaron Smith
: Re: Kevlar/Lexguard body armor.
: Lexguard (the laminated composite Lexan used as armor) is too
: bulky for use as body armor, IMO. While light weight,
: you're talking about a panel several inches thick. Its
: main application, as you found, was in stationary armor
: for buildings. Even armored limousine manufacturers prefer
: a glass/plastic composite, because Lexan would be too thick
: to form into windshields or windows. It might be useful in
: the faceplate of a helmet, however.
don't forget, plastics decay in ultraviolet light <sunlight>
Mike Chapman
Michael Knape <mkn...@medvideo.win.net> wrote:
#How can this be true? If it is true, you have no obligation to
#abide by a law of this type under our constitution. If you can
#legally buy it you can legally wear it.
Further investigation reveals that the original source of the illegal
body armor info is brain damaged. In virginia it is a class 4 felony
to wear body armor while committing a crime (I assume felony, although
maybe just for speeding or smoking pot for all I know). Otherwise
you are free to wear all the armor you want.
Julius Chang
#
[stuff deleted
#Make sure it's legal to wear body armor where you live. Here in Virginia
#it's either a Class 3 or Class 1 Misdemeanor (I can't remember which) to
#wear body armor.
#
Please cite the relevant section of the Virginia code.
I know of at least one store where you can purchase
soft armor over the counter and I've also seen them
sold openly at gun shows.
I suspect you are confusing the legality of wearing armor
with penalties for wearing body armor while in the commission
of a felony.
-Julius
David Ballard
: In article <3bv11i$k...@xring.cs.umd.edu>, dbal...@pinn.net (David Ballard) says:
: #Make sure it's legal to wear body armor where you live. Here in Virginia
: #it's either a Class 3 or Class 1 Misdemeanor (I can't remember which) to
: #wear body armor.
: I suspect you are confusing the legality of wearing armor
: with penalties for wearing body armor while in the commission
: of a felony.
Guilty as charged [see prior follow-up]. ;)
______________________________________________________________________________
David Ballard | "There are two powers only which are sufficient to control
dbal...@pinn.net | men and secure the rights of individuals and a peaceable
| administration; these are the combined force of religion
| and law, the force of fear and the bayonet."
| - NOAH WEBSTER
Eric A. Schwartz
Dillon Pyron <Dillon...@amd.com> wrote:
#
#Much about armouring deleted.
#
#The only problem with this design is that it has already been tried. In the
#Middle Ages. You have essentially designed a modern suit of armour, complete
#with the traditional problems. The advantage that soft armour gives is full
#motion. There is no way to provide for full motion and still have a
#rigid (Lexan
#in this case) torso. And jointing it just leaves little gaps for the
#inevitable
#"lucky shot" (which seems to occur more often than it should).
#
Modern space suits are rigid, yet provide a full range of motion.
Rigid plates are incorporated into modern Type IV armor
as is. The problem with medieval armor was that as firarms
got more and more powerful, the armor needed to counter them
grew heavier and heavier, because all they had was low-grade
steel. It was actually quite nimble in its original weight.
Now, we have lighter, stronger materials, and anyone with
any experience in ergonomics can look up the information
needed to provide quite a range of motion.
As to lucky shots, the Soviets had quite a problem with those
in some of their armored vehicles, due to their sloped glacis
plate. The bullets tended to deflect right into the optics
and aiming system if they hit the vehicle in the nose. So
they put ridges to catch the bullets on. Problem solved.
I do think that regular soft armor should make up the joints,
but if you do so, you have all-over superior protection.
The problem isn't that the armor is anergonomic; it's just that
while today's materials are better, so are today's guns. So
even with modern materials, the weight needed to stop
good rifle ammo is prohibitive.
E.S.