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Posted by DerbyDad03 on March 3, 2008, 11:07 am
> ransley wrote:
> > > On Mar 2, 6:50=EF=BF=BDpm, d...@manx.misty.com (Don Klipstein) wrote:
>
> > > > In <78d4d5e3-98db-4eaa-9304-b558bdcf0...@s8g2000prg.googlegroups.com=
>,
>
> > > > BobR wrote:
> > > > >On Mar 1, 1:10=EF=BF=BDam, letter...@invalid.com wrote:
> > > > >> Will epoxy harden in 20 degree weather? (outdoors)?
> > > > >> I have a livestock tank with a tiny leak. =EF=BF=BDI want to put =
some JB Weld
> > > > >> on it. =EF=BF=BDI have the quick dry stuff (supposed to dry in 5 =
minutes).
> > > > >> It's been in the house so at least the epoxy is warm. =EF=BF=BDMa=
ybe I should
> > > > >> put a hair dryer on it ourside?????
>
> > > > >It will be dependent on the epoxy being used. =EF=BF=BDSome epoxy w=
ill NOT
> > > > >cure period in cold weather which is why pre-preg fiberglass and
> > > > >carbon fiber is stored in the freezer.
>
> > > > =EF=BF=BD I think that uses one of the epoxy formulations that only =
cures at any
> > > > decent pace at elevated temperature, or else the shelf life in a fre=
ezer
> > > > is shorter than years on end.
>
> > > >http://www.gmtcomposites.com/technical_information.htm
>
> > > > =EF=BF=BD The pre-preg here lasts months in a freezer, is good for a=
bout a month
> > > > at room temperature, and it sounds to me from that page that curing =
is
> > > > achieved with 250 degrees F for an hour.
>
> > > > =EF=BF=BD This ain't the epoxy you get in a hardware store, and it s=
till does not
> > > > go forever without hardening in a freezer.
>
> > > > =EF=BF=BD- Don Klipstein (d...@misty.com)
>
> > > The epoxy you get in a hardware store still requires an exothermic
> > > reaction to cure. =EF=BF=BDCold will halt that reaction from occuring.=
=EF=BF=BDI use
> > > a number of different epoxy formulations from 5 minute epoxies to
> > > structural adhesives. =EF=BF=BDNone of them will cure in freezing
> > > temperatures. =EF=BF=BDThe key point remains to read the directions fo=
r the
> > > epoxy being use to determine the appropriate cure temperatures.- Hide =
quoted text -
>
> > > - Show quoted text -
>
> > I used JB weld at JB welds recomendations of 20f, it cured, and JB
> > said it would, it just took days. So what you state is wrong.
>
> NO, what I stated is totally accurate. =C2=A0I repeat, NONE of the epoxies=
> that I routinely use will cure at freezing temperatures. =C2=A0I don't use=
> JB Weld since it does not meet my needs in any use. =C2=A0JB Weld is NOT
> the only epoxy and every epoxy adhesive is formulated differently.
> Some may cure in cold temperatures, others may not. =C2=A0All require an
> exothermic reaction to cure and that reaction is dependent on
> formulation and temperature. =C2=A0Some formulations may be highly reactiv=
e
> and will cure in colder temperatures given adequate time and
> sufficient amounts. =C2=A0Others will never cure in cold.- Hide quoted tex=
t -
>
> - Show quoted text -
Bob R,
I guess it's all in how you parse your original statements. You
actually said a couple of different things, one of which is probably
accurate, and one which may not be.
Let's re-cap, in reverse:
re: I use a number of different epoxy formulations from 5 minute
epoxies to structural adhesives. None of them will cure in freezing
temperatures.
None of us can question the accuracy of that statement, since only you
know the types of products you use. I'd be willing to call it 100%
accurate, since I trust that you're not lying to us.
re: The epoxy you get in a hardware store still requires an exothermic
reaction to cure. Cold will halt that reaction from occuring.
The accuracy of that statement may be questionable. One could take
that to mean that *any* epoxy purchased at a hardware store will not
cure since "Cold will halt that reaction from occuring". If even one
brand of epoxy that will cure at cold temperatures is available in a
hardware store, then that statement wouldn't be accurate.
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