I used five minute epoxy diluted approx fifty percent with alcohol to coat the inside of a new model. After some twelve hours it still is not fully dry.
Anyone have any ideas on hoe to get the epoxy to fully cure?

You can try heating it with a heat gun and see if you can kick the epoxy to set. But more than likely it's not going to set. This is the problem with thinning epoxy with alcohol. If you use too much you change the chemical reaction, and instead of setting hard it will stay rubbery like that. If it doesn't set with heat then your best bet is going to be to scrape it off and redo it.

What I prefer to do if at all possible it use a heat gun to spread epoxy. Instead of thinning it out with alcohol, I use the heat to thin it. Use 30 minute epoxy because the heat shortens the set time, and anything less than 30 minute epoxy won't give you enough time to work. But put a "blob" of epoxy in the area you are working on, heat it with your heat gun, and use a epoxy brush to spread it over the area to be worked.

Hope this helps

Ken

Another thing you might try next time is finishing resin.

I like to use 20 minute. It's very thin and spreads easily. Makes a really nice finish.

It takes 24 hours to really set up good.

did you use 98%+ alcohol or just the 70% stuff. Sound like thats your problem. ya got too much water in it. 50% is also way too much. I wouldn't venture over 25%. Try 60% epoxy 20% glass balls and 20% alcohol. speads nice and is very light

When I dilute epoxy (for firewalls, etc ) I use acetone and dilute about 10% by volume.

For future reference you may also want to consider using clear (or colored ) fuel proof dope (Aerogloss ). Not as fuel proof as epoxy, but pretty good, and it drys quickly.

I bet if you wait another day it'll dry out. I wouldn't panic just yet. I use denatured alcohol which you can get at a hardware store. I've mixed it 50/50 and it dried nicely in a day or two. Be patient.

I've also had the same problem. Solved it by mixing another batch of epoxy and brushing it over the stuff that didn't cure. It worked.
Next time, you might consider using Balsa Rite. I painted a piece of balsa with it and put it in a baby food jar of 10 percent nitro and closed the lid. A week later, I took the balsa out and wiped it off with a paper towl and broke it. It snapped. It was just as dry as ever.

Like BB said, just wait...

Thinning epoxy with alcohol will increase the cure time.

Set it in a nice warm place (Like on top of your furnace) or aim a hair dryer at it and leave it for a day.

It is never a good idea to thin epoxy with alcohol. It is to easy to trap water (alcohol absorbs water from the atmosphere even if you start out with pure alcohol) in the mix and then you get the rubbery result. The alcohol you buy in the drug store can contain up to 50% water, use denatured alcohol if you must use alcohol. This is even worse with the quicker setting epoxies. Remember, epoxy does not DRY it CHEMICALLY CURES. The suggestion of adding heat sometime helps but leaves a weaker bond if the mix was formerly contaminated with water. Heat, if not excessive, in itself does not hurt the bond and will speed up the chemical reaction or curing process.

Thanks to all who took the time to answer my request for help. I tried the heat gun and then while warm wiped the excess off. I also rebrushed the area with alchol again and all seems to be working. Thanks for the help.
Merry Christmas.
Joe