1:1 ratio mix, did it in an 80 degree environment as suggested on label the surface is a 3 inch slab of oak about 3ft by 2ft, poured 3 separate coats 10 hours apart. Waited the suggested 72 hours for the full cure and all looked great, smooth clear surface, no bubbles and hard as a rock. I brought temperature in shop back down to the normal 60 degrees while building the base for the table and within 24 hours the surface became tacky again. could it possibly be still curing or was 72 hours not long enough and the batch is now trash along with my table?

 

I've had epoxy develop a bit of oily feel after cure, but not tacky exactly. I think your best bet would be to contact the tech support line for the epoxy you used. If it was West or System III they both have pretty good support.

 

What product specifically did you use? There is no such thing as just "epoxy" especially those that mix at a 1:1 ratio. Most that mix with a 1:1 ratio contain fillers or other components. Some are intended as base layers and will have a tacky finish when cured which is designed to aid adhesion of the next layer. Others include a wax that rises to the surface as it cures providing a protective coating that protects the epoxy during it's curing process.

Since the OP's resin mixes at a 1:1 ratio it's likely not a West or System III product. Most of them mix at a 2:1, 3:1 or 5:1 ratios.

 

its called pro marine supply, I just dont understand how it could cure hard then become tacky a few days later. here is the link to the ebay seller Crystal Clear Bar Table Top Epoxy Resin Coating for Wood Tabletop 1 Gallon Kit | eBay.

 

Are you sure you mixed equal parts of the epoxy well?

Table Top Epoxy Mixing Instructions - www.promarinesupplies.com
If any unmixed material remains on the side of the container and falls onto your surface while pouring it will leave an uncured wet or sticky spot.

 

I mixed well for 3 minutes and after I poured I disposed of the container so I did not scrap the sides clean, made that mistake on the first coat. I used a measuring cup from the grocery counter to measure 2 cups equal at a time. And again it cured fine nice hard and smooth to the touch and didn't become tacky until about day 5 well after the 72 hour mark.

 

You can pour another layer if the coating does not get smooth and hard.

Mixing should be done using the two cup method. Measure and mix in one container, then transfer the mixture to a 2nd container and and mix again. This will ensure that any unmixed material does not get onto the surface.

It is always best to use graduated containers like these: http://www.homedepot.com/p/Leaktite-...1CLR/203274784 Other sizes are available.