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epoxy
By:Paul G. Jacobson
Date: 11/29/2007, 4:52 pm
In Response To: Epoxy: epoxy (Thomas Duncan)

: has anyone ever baked small epoxy glue ups of wood pieces in a low temp oven
: for a couple hours? Like heat the oven up to about 200, turn off and let
: the piece sit in there? I'm in a bit of hurry! : )

In general: Heating a liquid epoxy mix will cause it to gel faster, once it has gelled heat will increased the polymerization of the resin. Once the resin has hardened a post treatment at an elevated temperature can harden and strengthen an epoxy mix.

Different brands and mixes of resins and hardeners are affected at different temperatures. Resins used for applications which require high strength are usually heat treated, and the temperature and time for the treatment will be something the manufacturer will be able to advise you about. Some resins don;t need this, and some don't respond to this.

When you mix your resin and hardener you create a thermoplastic. Once the resin has cured and hardened, if you apply enough heat to it, it will soften or melt. The temperature at which it softens will depend on the particular chemistry of the resin and hardener--and there are LOTS of epoxy resins and hardeners out there. For example, if your Thanksgiving turkey had a pop-up timer in it you might be interested in knowing that they use an epoxy cement to make those timers. The plunger compresses the spring, and is glued down with a resin which will soften at about 160 to 185 degrees F--the proper temperature of well-cooked poultry. The plunger stays down until the meat around the timer gets warm enough to heat the timer to the desired temperature. Then the plastic melts, the spring is no longer constrained, and up pops the plunger. All the epoxy (a tiny drop) stays inside the timer so no one eats it.

Hope you had a happy Thanksgiving.

PGJ

Messages In This Thread

Epoxy: epoxy
Thomas Duncan -- 11/25/2007, 5:45 pm
epoxy
Paul G. Jacobson -- 11/29/2007, 4:52 pm
Re: epoxy
Thomas Duncan -- 11/29/2007, 6:04 pm
steam
Paul G. Jacobson -- 11/29/2007, 7:53 pm
Re: steam
Thomas Duncan -- 11/29/2007, 8:50 pm
Re: steam
Paul G. Jacobson -- 11/30/2007, 6:01 am
Re: steam
Thomas Duncan -- 11/30/2007, 8:38 am
Re: epoxy
Mike Savage -- 11/29/2007, 7:42 pm
Re: Epoxy: epoxy
Rob Macks / Laughing Loon -- 11/26/2007, 5:05 pm
Re: Epoxy: epoxy
Toni V -- 11/26/2007, 7:55 am
Re: Epoxy: epoxy
Björn Thomasson -- 11/26/2007, 3:20 am
Re: Epoxy: epoxy
Thomas Duncan -- 11/25/2007, 10:01 pm
Re: Epoxy: epoxy
Don Goss -- 11/25/2007, 9:00 pm
Re: Epoxy: epoxy
Robin Boys -- 11/25/2007, 8:19 pm