X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Thu, 09 Apr 2009 13:01:22 -0400 Message-ID: X-Original-Return-Path: Received: from [66.64.141.200] (HELO lucky.dts.local) by logan.com (CommuniGate Pro SMTP 5.2.13) with ESMTP id 3574989 for lml@lancaironline.net; Thu, 09 Apr 2009 09:05:35 -0400 Received-SPF: none receiver=logan.com; client-ip=66.64.141.200; envelope-from=cjensen@dts9000.com Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01C9B914.53C9802E" X-MimeOLE: Produced By Microsoft Exchange V6.5 Subject: RE: [LML] Jefco X-Original-Date: Thu, 9 Apr 2009 09:08:51 -0400 X-Original-Message-ID: <8984A39879F2F5418251CBEEC9C689B3E86B08@lucky.dts.local> In-Reply-To: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [LML] Jefco Thread-Index: Acm4p45oxU1OefoPTHSRPvoTTR234QAauioQ From: "Chuck Jensen" X-Original-To: "Lancair Mailing List" This is a multi-part message in MIME format. ------_=_NextPart_001_01C9B914.53C9802E Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable "The jefco resin in the 5 gallon drums if left on a concrete floor or steel floor the resin can pull the cold up into the container and ruin the resin. Make sure the resin is stored properly for long use." =20 Not to put too fine a point on it, but 'cold' does not exist. Cold is = simply the absence of heat, so the heat in the Jefco may conduct down to = the cold floor, but such conduction is not a major factor in a media = freezing. The heat radiation and conduction to the surrounding air is a = much bigger loss. Some concrete slabs, in contact with the ground, may = actually stay warmer than the air and, ever so slightly, protect the = Jefco from freezing. =20 =20 Next, it should not be assumed that, because the Jefco got cold and = crystallized, that it is ruined. We use polymer by the ton, literally, = and if our polymer freezes and crystallizes, we must rewarm the polymer = to about 140F to dissolve the crystals. Thereafter, the efficacy of the = polymer is fully restored. =20 While this observation is pertinent to an epoxy and styrene system that = we use for a non-aviation purpose, it's important to understand that = such experience is fact specific; in this case, product specific. I = defer to the manufacturer of Jefco as to what their recommendation is = for their products. Out of an abundance of caution, they may say not to = use it for structural components, but I doubt there is any problem with = non-structural components. =20 =20 You can confirm the viability of the components if you do a PCP (process = control program) bench sample to confirm that the components cure to a = rock hard product when applied to a test strip. Chuck Jensen=20 -----Original Message----- From: Lancair Mailing List [mailto:lml@lancaironline.net]On Behalf Of = marv@lancair.net Sent: Wednesday, April 08, 2009 8:06 PM To: lml@lancaironline.net Subject: [LML] Jefco=20 Posted for "Justin Hawkins" : All Lancair customers the build shop did a test on the Jefco resin, if it gets close to freezing even for only a matter of minutes the resin can crystallize and its properties ruined. So if that happens clean the pump replace the resin. =20 The jefco resin in the 5 gallon drums if left on a concrete floor or steel floor the resin can pull the cold up into the container and ruin the resin. Make sure the resin is stored properly for long use.=20 =20 =20 =20 Justin Hawkins =20 Lancair Airframe & Technical Support =20 Lancair Int. Inc. =20 250 SE Timber AVE =20 Redmond, OR 97756 =20 justinh@lancair.com =20 =20 541-923-2244 ext 121 =20 =20 =20 -- For archives and unsub = http://mail.lancaironline.net:81/lists/lml/List.html ------_=_NextPart_001_01C9B914.53C9802E Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
"The=20 jefco resin in the 5 gallon drums if left on a concrete floor = or
 steel=20 floor the resin can pull the cold up into the container and = ruin
 the=20 resin. Make sure the resin is stored properly for long use."
 
Not to put too=20 fine a point on it, but 'cold' does not exist.  Cold is simply the = absence=20 of heat, so the heat in the Jefco may conduct down to the cold floor, = but such=20 conduction is not a major factor in a media freezing.  The heat = radiation=20 and conduction to the surrounding air is a much bigger loss.  Some = concrete=20 slabs, in contact with the ground, may actually stay warmer than the air = and,=20 ever so slightly, protect the Jefco from freezing. =20
 
Next, it=20 should not be assumed that, because the Jefco got cold and crystallized, = that it=20 is ruined.  We use polymer by the ton, literally, and if our = polymer=20 freezes and crystallizes, we must rewarm the polymer to about 140F to = dissolve=20 the crystals.  Thereafter, the efficacy of the polymer is = fully=20 restored.
 
While this=20 observation is pertinent to an epoxy and styrene system that we use for = a=20 non-aviation purpose, it's important to understand that such experience = is fact=20 specific; in this case, product specific.  I defer to the = manufacturer of=20 Jefco as to what their recommendation is for their = products.  Out of=20 an abundance of caution, they may say not to use it for structural = components,=20 but I doubt there is any problem with non-structural=20 components.  
 
You can confirm = the viability=20 of the components if you do a PCP (process control program) bench sample = to=20 confirm that the components cure to a rock hard product when = applied to a=20 test strip.

Chuck=20 Jensen
-----Original Message-----
From: Lancair Mailing = List=20 [mailto:lml@lancaironline.net]On Behalf Of=20 marv@lancair.net
Sent: Wednesday, April 08, 2009 8:06=20 PM
To: lml@lancaironline.net
Subject: [LML] Jefco=20

Posted for "Justin = Hawkins"=20 <JustinH@lancair.com>:

 All Lancair customers the = build shop=20 did a test on the Jefco resin, if
 it gets close to freezing = even for=20 only a matter of minutes the resin
 can crystallize and its = properties=20 ruined. So if that happens clean the
 pump replace the=20 resin.
 
 The jefco resin in the 5 gallon drums if = left on a=20 concrete floor or
 steel floor the resin can pull the cold up = into the=20 container and ruin
 the resin. Make sure the resin is stored = properly=20 for long use.
 
 
 
 Justin=20 Hawkins
 
 Lancair Airframe & Technical=20 Support
 
 Lancair Int. Inc.
 
 250 SE = Timber=20 AVE
 
 Redmond, OR=20 97756
 
 justinh@lancair.com=20 <mailto:justinh@lancair.com>
 
 541-923-2244 = ext=20 121
 
 
 

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