Applying Epoxy Coats

[wildboydoug]

I'm using East System epoxy with 834 hardener and will be applying the 6 oz fiberglass and first coat at the same time ... and was wondering how long after the first coat do i wait before applying the second coat? And how long after the second coat do i wait to apply the third coat? Should i sand between coats?

...doug

[Noah's]

Until it just starts to gel, about 3 hours at room temperature. If you can touch it and not have liquid epoxy on your finger it is ok to recoat

[wildboydoug]

So no sooner than about 3 hours ... thanks. Is there a maximum time to be aware of before i have to sand first before applying the next coat?

[Noah's]

Use higher temperatures or 833 Hardener to speed up gel and cure. A hair dryer will speed things up for small areas, just don’t overdue it or you will get air bubbles. If you can push your finger into the epoxy and leave a finger print or it clogs sandpaper it is OK to recoat without sanding. If you don’t leave a finger print, or can sand without clogging the paper the next coat will not adhere properly unless you sand thoroughly, this means take all the gloss off. My rule of thumb with 834 Hardener at room temperature is recoat the same day without sanding, but sand if you leave it overnight. About the only control you have over thin film epoxy set is temperature, lower slower, higher faster