acrylic vs polycarbonate on kitplante windshields
Holden
polycarbonate, and why?
My (limited) understanding is: Acrylic can be broken with a hammer in
the event of a crash, whereas polycarbonate is tougher and difficult
to break. Polycarbonate offers better bird strike protection than
acrylic, but also scratches easier than acrylic. Acrylic is easier to
form compound curves, but is harder to drill. Polycarbonate will craze
if gas gets on it. (Correct me if I am wrong here.)
Also, what is the largest size of acrylic or polycarbonate available?
4 ft x 8 ft?
Holden
Rich S.
news:56ebab77.03010...@posting.google.com...
> Also, what is the largest size of acrylic or polycarbonate available?
> 4 ft x 8 ft?
Are you thinking about copying W. Woman's invisible plane? ;-)
Rich S.
Rob Housman
know what kits use what materials, but I suppose I should ask Europa what is
included with my kit.
For some technical data on polymethylmethacrilate (Plexiglas, Perspex) go to
http://www.psrc.usm.edu/macrog/pmma.htm and the Roehm web at
http://www.roehm.de/en/plexiglas.html and for polycarbonate (Lexan) see
http://www.psrc.usm.edu/macrog/pc.htm and the General Electric web site
http://www.ge.com (where you will have to register in order to find anything
of value).
Neither material is particularly resistant to abrasion (without anti-scratch
coatings) but polycarbonate is somewhat better. The antiscratch coat on
polycarbonate CDs is so good that it is almost impossible to polish out
scratches. Neither is particularly resistant to organic solvents. Density
is about the same so weight is not a consideration for aircraft windscreens.
Polycarbonate is better for impact resistance so that would make it superior
for keeping birds out of your face, but could make it more difficult to exit
a damaged aircraft. Both are available in sheets larger than 4 X 8.
Best regards,
Rob Housman
Europa XS Tri-Gear
"Holden" <holden...@yahoo.com> wrote in message
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Gordon Hanka
coating on the lexan headlights covers on new cars seems pretty impregnable.
Gordon
"Rob Housman" <robho...@sbcglobal.net> wrote in message
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highflyer
That sounds right to me. I would not use polycarbonate for a windshield
myself. :-)
You can get it in larger sizes but it would be a special order and
rather expensive. :-)
--
Highflyer
Highflight Aviation Services
MJC
being that acrylic, by the nature of how it is made, will give you better
optics as well.
Acrylic doesn't typically have the "wave" you sometimes have to look
through in a poly canopy.
M
"Holden" <holden...@yahoo.com> wrote in message
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Mark E. Anderson
UV much faster than acrylic. there are coatings to prevent this so
if the polycarb is your preference, be sure to get such a coating.
--
mark anderson "I had a little bird. Its name was "Enza".
wombats.near.nmrfam.wisc.edu Opened up the window, in flew Enza."
http://www.nmrfam.wisc.edu childrens' rhyme, 1918
at, near, all the same.
Qaz
tinting wind shields?
"Rob Housman" <robho...@sbcglobal.net> wrote in message
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Ron Wanttaja
>Is the same stuff they make glasses out of. If so why can't we get self
>tinting wind shields?
'Cause it'd be dangerous if you flew into a tunnel. :-)
Ron Wanttaja
Morgans
"Qaz" <j...@gt.rr.com> wrote in message
news:6aoT9.24658$Pb.5...@twister.austin.rr.com...
> Is the same stuff they make glasses out of. If so why can't we get self
> tinting wind shields?
If you gotta nuf green, you could. The stuff that makes the tint is a
coating, and plus it is scratch resistant!
--
Jim in NC
Dillon Pyron
<DontSpamM...@comcast.net> wrote:
>Is it feasible to put anti-scratch coating on a canopy? The anti-scratch
>coating on the lexan headlights covers on new cars seems pretty impregnable.
>
>Gordon
The problem is, I think the coating has little rock magnets in it!!!
I've replaced one or the other a total of three times now. Either
that or we need to get those 18-wheel dump trucks off MoPac (Austin,
Tejas).
dillon
Morgans
"Dillon Pyron" <dmp...@austin.rr.com> wrote in message
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At the price for those things, I would have to consider some of those little
wire thingies to protect them. My 1987 Chevy van with 208,000 miles, on the
other hand, doesn't really care if it takes a hit or three. <g>
--
Jim in NC
Richard Lamb
What works?
What doesn't?
John Ammeter
One caveat is that you can't heat and bend Lexan without
first removing the moisture from it. Yes, it has water in
the plastic. If you heat it up to 250 degrees to bend it,
it will fog up from the vapor in the plastic. You first
have to heat it up to 200 degrees for long enough to drive
out the water content. I don't recall the length of time
but I think it was about an hour.
Plexiglass doesn't have that problem. You can simply heat
it up to the plastic point and form it or bend it.
john
David Rahman
David
Bob Kuykendall
> Any first hand experience heat forming plastics?
No, sorry.
> What works?
For me, what has worked fabulously is making or obtaining a male plug,
and delivering it to Aircraft Windshields, Inc (in Los Alamitos, CA)
with a note that says "make me X number of these." I've also had good
luck with notes that say "use the plug for Y glider, but trim it thus
and so."
The rule that I have resolved to follow is that when I think I'll be
making more than about 20 units a year, I'll consider getting into the
acrylic business. Until then, I think that it is most cost- and
time-effective to pay others to address the problems.
But that's just me, and it's driven by criteria that might have no
bearing on your situation. For you, it's going to be different.
> What doesn't?
Here's a reasonable article by Rick Hubka on the topic:
http://www.hubka.com/to_build_a_canopy.htm
Thanks, and best regards to all
geo
Natural Light Black and White Photography
http://www.phastnet.com/~geos/
-George-
"Gordon Hanka" <DontSpamM...@comcast.net> wrote in message
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Gordon Hanka
coatings.
gordon
"geo" <n...@no.com> wrote in message news:3e20df0d$1...@news.teranews.com...
geo
>
David Rahman
the stuff needed to give a light weight windshield some extra strength and shatter
protection strait ahead,and still leave the side portions smashable to alow for
emergency escape on the ground.
David
Nolaminar
can't be formded in such a manner.
Lexan (PolCarb) is a lot easier to work with and does not crack as Plexiglas
(Acrylic)
Richard Lamb
Never tried heat forming it tho.
Dave
I've bent it in a brake, works fine,,, just scary the first time...
Lexan can only be heat molded if essentially cured out in a dry
hot oven. It takes about 1 hour per 1/16 inch of thickness in my
limited experience.... At about 180 to 200 degrees F. If you cold
bend it and put 1 drop of gasoline on the bend it will craze and
break/shear. You can vacume form it some when hot (I think it was
at 250 deg F)with a buc and a good large pump. I cut it with a
good carbide blade in a skillsaw. I was building the small
windshields/wind deflectors for a Formula Car.
BTW I have never built any part of a plane (yet)
I currently support race-cars as a second job in the summer.
--
/David Taylor /
/Portland OR /