X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Thu, 09 Apr 2009 20:24:41 -0400 Message-ID: X-Original-Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.122] verified) by logan.com (CommuniGate Pro SMTP 5.2.13) with ESMTP id 3575745 for lml@lancaironline.net; Thu, 09 Apr 2009 17:20:45 -0400 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.122; envelope-from=super_chipmunk@roadrunner.com Received: from Laptop ([74.75.176.139]) by cdptpa-omta04.mail.rr.com with SMTP id <20090409212007.IIUG2520.cdptpa-omta04.mail.rr.com@Laptop> for ; Thu, 9 Apr 2009 21:20:07 +0000 X-Original-Message-ID: <17EC7C7670464D79AC89C3990467D725@Laptop> From: "Bill Wade" X-Original-To: "Lancair Mailing List" References: In-Reply-To: Subject: Re: [LML] Re: Jefco X-Original-Date: Thu, 9 Apr 2009 17:20:16 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_02E3_01C9B937.738BC750" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Windows Mail 6.0.6001.18000 X-MimeOLE: Produced By Microsoft MimeOLE V6.0.6001.18049 This is a multi-part message in MIME format. ------=_NextPart_000_02E3_01C9B937.738BC750 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I had the Jeffco resin crystallize on me- I turned the thermostat down = below 60 to save oil and have a more comfortable working environment. I = don't think the temp got below 50, it certainly didn't get near = freezing. The spec sheets for the resin and hardener recommend storage = temps of 65- 80 degrees. I guess they mean it. I've never had hardener = crystallize, just the resin. I do keep the containers up high to avoid = drafts along the floor since that happened. When resin crystallizes you can see a milky or foggy layer at the = bottom of the container (1 gallon plastic). I've had this happen with = other resin systems as well and what I did was to heat the container in = a hot tap water bath until the crystals redissolved. My pump is all- = metal and I played a heat gun on it to slowly thaw the affected areas. = After redissolving the Jeffco I used it as normal and it appeared to = harden fully with good adhesion but I haven't done any peel or hardness = testing. I tried to contact Jeffco today but the phone numbers are = discontinued and the website information I had no longer works. Hmmm. I would echo Chuck Jensen that Jeffco might recommend non-structural = use (filler/ micro) and the best solution would be to make test coupons = as you go. A drill press can be used with a spring scale and a dial = indicator to compare hardness of epoxy samples. Just chuck a sharp = center punch, use the spring scale to pull the handle and measure = travel/penetration with the dial indicator. Something else to think about- the containers I have also show a "best = by" date on the labels. FWIW when joining cured fiberglass parts (as = opposed to taping with BID) I've been using Hysol instead of flox. My = take on what I've read is that a secondary bond should have some "give" = to it and Hysol doesn't seem as brittle as the Jeffco. -Bill Wade ------=_NextPart_000_02E3_01C9B937.738BC750 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

I had the Jeffco resin = crystallize on=20 me- I turned the thermostat down below 60 to save oil and have a more=20 comfortable working environment. I don't think the temp got below 50, it = certainly didn't get near freezing. The spec sheets for the resin and = hardener=20 recommend storage temps of 65- 80 degrees. I guess they mean = it. I've never=20 had hardener crystallize, just the resin. I do keep the = containers up high=20 to avoid drafts along the floor since that happened.

When resin crystallizes you can = see a milky=20 or foggy layer at the bottom of the container (1 gallon plastic). I've = had this=20 happen with other resin systems as well and what I did was to heat the = container=20 in a hot tap water bath until the crystals redissolved. My pump is = all-=20 metal and I played a heat gun on it to slowly thaw the=20 affected areas. After redissolving the Jeffco I used it as = normal=20 and it appeared to harden fully with good adhesion but I haven't = done any=20 peel or hardness testing. I tried to contact Jeffco today but the phone = numbers=20 are discontinued and the website information I had no longer works. = Hmmm.

I would echo Chuck = Jensen that=20 Jeffco might recommend non-structural use (filler/ micro) and the best = solution=20 would be to make test coupons as you go. A drill press can be used with = a spring=20 scale and a dial indicator to compare hardness of epoxy = samples. Just=20 chuck a sharp center punch, use the spring scale to pull the handle and = measure=20 travel/penetration with the dial indicator.

Something else to think about- = the containers=20 I have also show a "best by" date on the labels. FWIW when joining cured = fiberglass parts (as opposed to taping with BID) I've been using = Hysol=20 instead of flox. My take on what I've read is that a secondary bond = should=20 have some "give" to it and Hysol doesn't seem as brittle as the = Jeffco. =20 -Bill Wade

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