I have been conducting a rod building class for Project Healing Waters Fly Fishing here in Omaha. Its been great fun and the rods are coming along really well. But, and a big but, some of my Veterans have complained that the epoxy isn't drying. That it stays tacky forever. They say they are mixing according to the directions, 50/50 mix. I checked the epoxy and it is a 1;1 mixture. So I am at a loss to explain why its not curing. The only thing it could be is old epoxy. So what is the shelf life of two part epoxy? Is there any way to change the mixture to make it harden?

Thanks.

It is not a shelf life issue! The reasons for epoxy not curing are these, 1) improper mix quantities (ie. not 50/50) 2) Not thoroughly mixed. 3) Cold temperature where curing. If you can eliminate #3, it is one or both of the others..

Phil Erickson Wrote:
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> It is not a shelf life issue! The reasons for
> epoxy not curing are these, 1) improper mix
> quantities (ie. not 50/50) 2) Not thoroughly
> mixed. 3) Cold temperature where curing. If you
> can eliminate #3, it is one or both of the
> others..


We are testing the epoxy now. I should have an answer by the morning, at least I hope I will.

My first question would be, "How are they measuring the two parts?"

John

Phil is correct. Epoxy can do nothing except cure provided the proportions are correct (not close enough but spot on), it is thoroughly mixed (not just stirred around but well mixed), and the temperature is about 70 degrees or more. The additional cure time in a 65 degree room can be surprisingly longer than the cure time in a 70 degree room.

Some epoxy finishes, such as ProKote's medium viscosity epoxy, that have more generous open time take a bit longer to cure. First time I used ProKote I was in full panic mode after about 6 hours. But after cranking up a space heater overnight, all was well the next morning.

The good news is a fresh coat of epoxy (well measured and mixed in a warm place) will usually cure (pun intended) the problem.

John

I should have added that if after 24 hours in a warm place all the applied finish is still not cured, the #1 suspect would be inaccurate measuring and unequal volumes of resin and hardener. If some wraps have cured and others remain uncured, then mixing is a more probable suspect.

And to your last question, no, mixing other than 50 / 50 by volume is the odds on favorite to make an aggravating situation worse.

Phil Erickson Wrote:
-------------------------------------------------------
> It is not a shelf life issue! The reasons for
> epoxy not curing are these, 1) improper mix
> quantities (ie. not 50/50) 2) Not thoroughly
> mixed. 3) Cold temperature where curing. If you
> can eliminate #3, it is one or both of the
> others..


We are testing the epoxy now. I should have an answer by the morning, at least I hope I will.

John,
Slowly mix the epoxy for a minimum of 120 seconds or 2 minutes as measured by a clock. Longer is even better.

I use a plastic mixing cup, and a craft stick with the end of the stick ground flat, with slightly rounded edges to avoid cutting the cup.

As I mix, I frequently wipe the sides of the cup and scrape off the stick on the side of the cup, to insure that ALL parts of the mix have been completely mixed.

I had the same issue on a couple of my first builds. When I asked why - it was suggested to me, that it could be incomplete mixing and to do a 120 second or 2 minute mix by the clock.

Take care

Phil has it right on the head and Roger has great suggestions. if you are mixing less than 3cc and not using syringes it could be the cause. it has to be dead on and two minutes is the minimum I mix the batch larger quantities three minutes.

Tom

Alright, John. How did it end?

I have struggled with this also. Temperature and humidity matter. I also used the little tin flat that extends the working time of the epoxy. Well everything I used this thing it has taken the epoxy quite a while several days before I could wrap over the top. I did have issues once with the epoxy the I got from healing waters. But am unsure which parameter was out of whack. Tell the guys to mix for 5 minute or so all the time scraping the bottom and sides of the cup and try to stay away from the metal mixing cups.

Just my opinion.

David C.L'Heureux
ET2 (SW/AW) USA RET
100% Disabled Veteran

David C. L'Heureux
ET2 (SW/AW) USA RET.
100% Disabled Veteran