Although my kit was delivered with the (semi-transparent) brown windows I
returned them in exchange for clear, untinted, windows. I plan to do some
night flying and am willing to accept a bit more heat during the day in
exchange for a lot more visual acuity at night.
Best regards,
Rob Housman
A070
----- Original Message -----
From: "J R (Bob) Gowing" <gowingjr@acr.net.au>
"Europa Group" <europa@avnet.co.uk>
Subject: Re: Use of White Pigment with Ampreg 20
> Dear All
>
> Since older people need 8 times the light input to see as well as a
younger
> person I had another material which lets in more light but blocks UV (b &
a)
> almost entirely. It is VE003.
>
> The Brown 504 which is the normal Europa dark brown windscreen material
> starts transmitting UV (b) (300 or so nm) and transmits about 35% at 380
nm.
> It transmits UV (ba) to 400 nm about 40%. Light and heat over 600 nm is
> transmitted from the source used in the test about 65 to 70% up to 1600
> nm.according to the graph supplied me.
>
> JR (Bob) Gowing in Oz Kit 327
>
> ----- Original Message -----
> From: "Rob Housman" <ROB-HOUSMAN@worldnet.att.net>
> Subject: Re: Use of White Pigment with Ampreg 20
>
>
> > It is a common mis-conception that glass blocks 100% of the UV light.
> Check
> > this link http://www.jersey.net/~edsci/techsup/GlassCurve.pdf for a
graph
> > showing transmission at various wavelengths for 5mm thick glasses.
> >
> > The UV portion of the spectrum is generally taken to be 400nm or less
> > (1000nm = 1 micrometer, or 1 micron if you prefer). In this list I am
> > familiar only with the first three types listed: Borofloat would be
> similar
> > to window glass, Pyrex is Corning's name for tempered glass, and BK7 is
> > commonly used for mirrors or lenses.
> >
> > Optical plastics, e. g., CR-39 and polycarbonate that are used in
plastic
> > eyeglass lenses, have UV absorbers in the mix but I doubt that the
windows
> > in the Europa have an absorber, and your experience confirms this
> suspicion.
> >
> >
> > Best regards,
> >
> > Rob Housman
> > A070
> >
> >
> > ----- Original Message -----
> > From: "LTS" <lts@avnet.co.uk>
> > Subject: Re: Use of White Pigment with Ampreg 20
> >
> >
> > > I am not on a topic that I know much about here but:
> > >
> > > 1 I thought Rayban used glass in their sunglasses for 100% UV
> block????
> > > 2 I get a great sun tan whilst flying and I have a plastic
canopy????
> > >
> > > Jerry
> > > LTS@avnet.co.uk
> > > www.avnet.co.uk/touchdown
> > > ----- Original Message -----
> > > From: "J R (Bob) Gowing" <gowingjr@acr.net.au>
> > > <roger.mills@btinternet.com>; <europa@avnet.co.uk>
> > > Subject: Re: Use of White Pigment with Ampreg 20
> > >
> > >
> > > > Thank you fellas for your comments.
> > > >
> > > > Dave S, I take your point that the UV is a serious matter and that
is
> > the
> > > > reason for my reply to Roger as follows:-
> > > >
> > > > Roger, I put a lot of laminated glass in the front extension of our
> > > house -
> > > > to get the plastic layer in between the 2 layers of glass. That is
the
> > > part
> > > > that keeps out the UV.
> > > >
> > > > Fred F, I intend taking your advice and forget about using any White
> > > pigment
> > > > in the epoxy itself.
> > > >
> > > > Thank you all for your inputs.
> > > > Sincerely
> > > > JR (Bob) Gowing in Oz Kit 327
> > > >
> > > > ----- Original Message -----
> > > > From: "Dave Simpson" <davesimpson@londonweb.net>
> > > > Subject: Re: Use of White Pigment with Ampreg 20
> > > >
> > > >
> > > > > Bob,
> > > > >
> > > > > At work, a sub-contractor used white pigment in the epoxy/glass
lay
> up
> > > for
> > > > a
> > > > > very large radome mounting ring (3m dia.) for a microwave test
site.
> > > The
> > > > > rig has been completely outdoors for almost 4 years now and shows
no
> > > sign
> > > > of
> > > > > UV degradation. It also has a blue foam base. The laminate was
> much
> > > > > thicker that our Europas but the environmental exposure was more
> > severe
> > > > too.
> > > > >
> > > > > Dave Simpson
> > > > >
> > > > > ----- Original Message -----
> > > > > From: J R (Bob) Gowing <gowingjr@acr.net.au>
> > > > > Subject: Use of White Pigment with Ampreg 20
> > > > >
> > > > >
> > > > > > I have just read the pamphlet that came with my latest supply of
> > Slow
> > > > > > Hardening Ampreg 20 and 2 year shelf life. It states that up to
> 10%
> > by
> > > > > > volume of SP epoxy pignents can be added to the resin component
> and
> > > then
> > > > > > this mix can be combined in the same old weight ratio of 100:25.
> > > > > >
> > > > > > It may be that using the available white pigment in the
finishing
> > > phase
> > > > > > might reduce the amount of paint needed for satisfactory cover
and
> > UV
> > > > > > protection.
> > > > > >
> > > > > > Has anyone something useful to report about using SP white
pigment
> > in
> > > > the
> > > > > > mix to finish their wings?
> > > > > >
> > > > > > JR (Bob) gowing, Kit 327 in Oz.
> > > > > >
> > > > > >
> > > > > > The Europa List is supported by Aviators Network UK -
> > info@avnet.co.uk
> > > > > >
> > > > >
> > > >
> > > >
> > > > The Europa List is supported by Aviators Network UK -
info@avnet.co.uk
> > >
> > >
> >
> >
>
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