<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns:p="urn:schemas-microsoft-com:office:powerpoint" xmlns:a="urn:schemas-microsoft-com:office:access" xmlns:dt="uuid:C2F41010-65B3-11d1-A29F-00AA00C14882" xmlns:s="uuid:BDC6E3F0-6DA3-11d1-A2A3-00AA00C14882" xmlns:rs="urn:schemas-microsoft-com:rowset" xmlns:z="#RowsetSchema" xmlns:b="urn:schemas-microsoft-com:office:publisher" xmlns:ss="urn:schemas-microsoft-com:office:spreadsheet" xmlns:c="urn:schemas-microsoft-com:office:component:spreadsheet" xmlns:oa="urn:schemas-microsoft-com:office:activation" xmlns:html="http://www.w3.org/TR/REC-html40" xmlns:q="http://schemas.xmlsoap.org/soap/envelope/" xmlns:D="DAV:" xmlns:x2="http://schemas.microsoft.com/office/excel/2003/xml" xmlns:ois="http://schemas.microsoft.com/sharepoint/soap/ois/" xmlns:dir="http://schemas.microsoft.com/sharepoint/soap/directory/" xmlns:ds="http://www.w3.org/2000/09/xmldsig#" xmlns:dsp="http://schemas.microsoft.com/sharepoint/dsp" xmlns:udc="http://schemas.microsoft.com/data/udc" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:sps="http://schemas.microsoft.com/sharepoint/soap/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:udcxf="http://schemas.microsoft.com/data/udc/xmlfile" xmlns:wf="http://schemas.microsoft.com/sharepoint/soap/workflow/" xmlns:mver="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns:mrels="http://schemas.openxmlformats.org/package/2006/relationships" xmlns:ex12t="http://schemas.microsoft.com/exchange/services/2006/types" xmlns:ex12m="http://schemas.microsoft.com/exchange/services/2006/messages" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 12 (filtered medium)">
<!--[if !mso]>
<style>
v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style>
<![endif]-->
<style>
<!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p
{mso-style-priority:99;
mso-margin-top-alt:auto;
margin-right:0in;
mso-margin-bottom-alt:auto;
margin-left:0in;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
tt
{mso-style-priority:99;
font-family:"Courier New";}
span.EmailStyle19
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page Section1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.Section1
{page:Section1;}
-->
</style>
<!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body bgcolor=white lang=EN-US link=blue vlink=purple>
<div class=Section1>
<p class=MsoNormal><span style='font-family:"Calibri","sans-serif"'>If there’s
one thing I hate, it’s the paint job on my bombs loosing their gloss from
excess shrinkage of the epoxy. <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-family:"Calibri","sans-serif"'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> nsrca-discussion-bounces@lists.nsrca.org
[mailto:nsrca-discussion-bounces@lists.nsrca.org] <b>On Behalf Of </b>Dr. Mike
Harrison<br>
<b>Sent:</b> Monday, November 26, 2007 11:00 AM<br>
<b>To:</b> NSRCA Mailing List<br>
<b>Subject:</b> Re: [NSRCA-discussion] epoxy question-I am back<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Gray,</span><o:p></o:p></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>I
am pleased to see your scientific answer. It is very helpful and I would
love to have the epoxy you could make up. I thought about putting my
existing mix full strenght but I know I could never get all the excess
out. Fortunately, having a weakened epoxy has no real detrimental effects
on glassing a wing. With the info you have given it will lead me to delay
primer for a while. I would think the solvent evaporation rate would be
inversely exponential, meaning most of the evaporation/shrinkage would occur
within a couple of months. Since it is a model and not a bomb, there is
room for lax tolerances. </span><o:p></o:p></p>
</div>
<div>
<p class=MsoNormal> <o:p></o:p></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Thanks</span><o:p></o:p></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Mike</span><o:p></o:p></p>
</div>
<blockquote style='border:none;border-left:solid black 1.5pt;padding:0in 0in 0in 4.0pt;
margin-left:3.75pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt'>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>-----
Original Message ----- <o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal style='background:#E4E4E4'><b><span style='font-size:10.0pt;
font-family:"Arial","sans-serif"'>From:</span></b><span style='font-size:10.0pt;
font-family:"Arial","sans-serif"'> <a href="mailto:gfowler@raytheon.com"
title="gfowler@raytheon.com">Gray E Fowler</a> <o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>To:</span></b><span
style='font-size:10.0pt;font-family:"Arial","sans-serif"'> <a
href="mailto:nsrca-discussion@lists.nsrca.org"
title="nsrca-discussion@lists.nsrca.org">NSRCA Mailing List</a> <o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Sent:</span></b><span
style='font-size:10.0pt;font-family:"Arial","sans-serif"'> Monday, November 26,
2007 9:23 AM<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Subject:</span></b><span
style='font-size:10.0pt;font-family:"Arial","sans-serif"'> Re:
[NSRCA-discussion] epoxy question-I am back<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><o:p> </o:p></p>
</div>
<p class=MsoNormal style='margin-bottom:12.0pt'><br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>1.
"Thinning the epoxy saves no weight by evaporation. There is
virtually no evaporation and no weight loss-a big time erroneous assumption on
my part. So if you mix 2 ounces of epoxy and add 2 ounces of thinner and
put it all on the airplane, you have added 4 ounces to the airplane.
"</span> <br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>After seeing
the real question I expected a weight increase of at least 9% (how much water
in the mix). If you put 1oz (by weight) of solvent in 1 oz of epoxy, and apply
it as a coating , thin, you will eventually end up with 1 oz of epoxy. Mike, your
solvent got trapped, and now it will have less adhesion, less tensile,
Compression and flexure strength, and will now shrink slowly as the alcohol
exits the cured epoxy, over a year or so (see Wayne's answer).</span> <br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>None of the
solvent's listed will react with any epoxy blend. Exotherm is negligible when
applied as a thin coating, but significant in mass. The ability to have the
solvent evaporate out of the epoxy coating is directly related to the mixed
viscosity of the neat epoxy blend and the cure rate of the epoxy. Those of you
who ran experiments with 5 minute epoxy reported bad results because of high
viscosity and fast cure rate.The high viscosity (even Mike's blend is
apparently too high) will cause a skin effect where the solvent evaporates from
the surface first, creating a high viscosity skin, then the epoxy starts to
cure increasing viscosity even more, thus trapping the solvent. Using
fiberglass makes this even worse. MIKE- in one year from now your wings will
weigh less.</span> <br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>So it sounds
like the the Pattern Dudes of the world need a solution. What AeroSlave
can do is provide a super low viscosity epoxy for sale. This will be 100%
solids (which means NO solvents). Chances are, as a mixed epoxy, the viscosity
will be lower than even blends with some solvent in them. This can be used to
apply fiberglass to wings or as a general laminating resin.</span> <br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>How much
interest would there be for such a a product? It would probably cost about $50/
quart, $25/ pint. It would absolutely require an accurate scale (+/- 1 gram) to
WEIGH the epoxy and hardener into the appropriate mix ratio. AND I offer no
warranty, simply because you guys are the biggest bunch of experimenters in the
world, and I cannot control, nor anticipate how this could get screwed up.</span>
<br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>1. Operator
cannot operate a scale.</span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>2. Operator has
a crappy scale.</span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>3. Operator
added solvent anyway because thats how he has always done it...since 1976</span>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>4. Operators
basement is 100% realative humidity..condensation on the wing.</span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>5. Operator
added "more" hardener to make it cure faster.</span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>6.
Operator......(enter F/U here).</span> <br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>As you can see
there is one common theme to all of these possible problems, Operator, i.e.
customer.</span> <br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>So if you are
STILL interested please respond and Lance and I will take it under advisement.</span>
<br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> </span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><br>
<br>
<br>
Gray Fowler<br>
Senior Principal Chemical Engineer<br>
Radomes and Specialty Apertures<br>
Technical Staff Composites Engineering<br>
Raytheon</span> <br>
<br>
<o:p></o:p></p>
<table class=MsoNormalTable border=0 cellpadding=0 width="100%"
style='width:100.0%'>
<tr>
<td width="40%" valign=top style='width:40.0%;padding:.75pt .75pt .75pt .75pt'>
<p class=MsoNormal><b><span style='font-size:7.5pt;font-family:"Arial","sans-serif"'>"Dr.
Mike Harrison" <drmikedds@sbcglobal.net></span></b><span
style='font-size:7.5pt;font-family:"Arial","sans-serif"'> </span><br>
<span style='font-size:7.5pt;font-family:"Arial","sans-serif"'>Sent by:
nsrca-discussion-bounces@lists.nsrca.org</span> <o:p></o:p></p>
<p><span style='font-size:7.5pt;font-family:"Arial","sans-serif"'>11/23/2007
01:57 PM</span> <o:p></o:p></p>
<table class=MsoNormalTable border=1 cellpadding=0>
<tr>
<td valign=top style='background:white;padding:.75pt .75pt .75pt .75pt'>
<p class=MsoNormal align=center style='text-align:center'><span
style='font-size:7.5pt;font-family:"Arial","sans-serif"'>Please respond to<br>
NSRCA Mailing List <nsrca-discussion@lists.nsrca.org></span><o:p></o:p></p>
</td>
</tr>
</table>
</td>
<td width="59%" valign=top style='width:59.0%;padding:.75pt .75pt .75pt .75pt'>
<table class=MsoNormalTable border=0 cellpadding=0 width="100%"
style='width:100.0%'>
<tr>
<td valign=top style='padding:.75pt .75pt .75pt .75pt'>
<p class=MsoNormal align=right style='text-align:right'><span
style='font-size:7.5pt;font-family:"Arial","sans-serif"'>To</span><o:p></o:p></p>
</td>
<td valign=top style='padding:.75pt .75pt .75pt .75pt'>
<p class=MsoNormal><span style='font-size:7.5pt;font-family:"Arial","sans-serif"'>"NSRCA
Mailing List" <nsrca-discussion@lists.nsrca.org></span> <o:p></o:p></p>
</td>
</tr>
<tr>
<td valign=top style='padding:.75pt .75pt .75pt .75pt'>
<p class=MsoNormal align=right style='text-align:right'><span
style='font-size:7.5pt;font-family:"Arial","sans-serif"'>cc</span><o:p></o:p></p>
</td>
<td valign=top style='padding:.75pt .75pt .75pt .75pt'></td>
</tr>
<tr>
<td valign=top style='padding:.75pt .75pt .75pt .75pt'>
<p class=MsoNormal align=right style='text-align:right'><span
style='font-size:7.5pt;font-family:"Arial","sans-serif"'>Subject</span><o:p></o:p></p>
</td>
<td valign=top style='padding:.75pt .75pt .75pt .75pt'>
<p class=MsoNormal><span style='font-size:7.5pt;font-family:"Arial","sans-serif"'>[NSRCA-discussion]
epoxy question</span><o:p></o:p></p>
</td>
</tr>
</table>
<p class=MsoNormal><o:p> </o:p></p>
<table class=MsoNormalTable border=0 cellpadding=0>
<tr>
<td valign=top style='padding:.75pt .75pt .75pt .75pt'></td>
<td valign=top style='padding:.75pt .75pt .75pt .75pt'></td>
</tr>
</table>
</td>
</tr>
</table>
<p class=MsoNormal><br>
<br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>I have read
with interest all the comments and some of you have educated me on this issue.
If I may, I will share what I have learned.</span> <br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>1.
Thinning the epoxy saves no weight by evaporation. There is
virtually no evaporation and no weight loss-a big time erroneous assumption on
my part. So if you mix 2 ounces of epoxy and add 2 ounces of thinner and
put it all on the airplane, you have added 4 ounces to the airplane. </span>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>2. The
properties of the epoxy are changed-it becomes rubbery.</span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>3.
Changing the properties is not an issue regarding finishing the
airplane(painting)</span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>4. Using
thinned epoxy is fine for applying glass cloth.</span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>5. I have
tried MEK(epoxy thinner), denatured alcohol, 91%alcohol, acetone. My
preference is denatured alcohol because it is the safest and most economical, I
think. I thought MEK would be the answer. It is the worst of the
bunch. </span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>6. The
best way to glass surfaces is to thin the epoxy and apply as sparingly as
possible. A way to do that is to apply and wipe off excess with paper
towels. </span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>7. It is
almost exactly 2 ounces to glass a wing panel complete, so 4 ounces for a whole
wing. About 2 ounces for a stab. Properly done wings and stab
glassed and painted is 2-2.5 times the weight of monokote. </span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>8. A
second thinned coat of epoxy on the glassed wing is .75 ounces each wing
panel-1.5 oz total.</span> <br>
<br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Pick your
poison.</span> <br>
<br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Later,</span> <br>
<span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Mike</span> <br>
<tt><span style='font-size:10.0pt'>_______________________________________________</span></tt><span
style='font-size:10.0pt;font-family:"Courier New"'><br>
<tt>NSRCA-discussion mailing list</tt><br>
<tt>NSRCA-discussion@lists.nsrca.org</tt><br>
<tt>http://lists.nsrca.org/mailman/listinfo/nsrca-discussion</tt></span> <o:p></o:p></p>
<div class=MsoNormal align=center style='text-align:center'>
<hr size=2 width="100%" align=center>
</div>
<p class=MsoNormal>_______________________________________________<br>
NSRCA-discussion mailing list<br>
NSRCA-discussion@lists.nsrca.org<br>
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion<o:p></o:p></p>
</blockquote>
</div>
</body>
</html>