Builders' Forum Archives
Re: sand paper grit
Posted by Mac on Mar 18, 2005
I agree with all you said except sanding through the outer surface of epoxy to expose the less cured epoxy underneath. To my understanding - and Lord knows I often don't understand - epoxy cures evenly inside and outside at the same time, unlike paint which dries outside in. Therefore, when sanding for adhesion, we're roughing-up for a mechanical bond and not exposing green epoxy for a chemical bond. Now, speaking of chemical bonds:
I've had good luck applying multiple coats of slo cure epoxy at about 68 degrees within 5 hours of each other without sanding. The epoxy is soft enough for a chemical bond. I always carbide scrape any runs or sags first. (They never go away with recoating - only get bigger).
If I'm wrong about any of this, please set me straight.
In Response to: Re: sand paper grit by Gert Walter on Mar 18, 2005