Tips for making wood and epoxy coasters as wedding gifts

I did a coaster set for my sister's engagement last spring and ran into the sinking problem too, except I learned about it after the fact when the middle dipped below the edges on half of them. Had to mix up small top-off batches a day later, and the two-part pour shows a faint line if you look hard. Your approach of pouring proud and sanding back is smarter and I'll do it that way next time.

One thing that helped me with the marbling was using dry mica powder instead of a liquid pigment. The liquid tint seemed to spread everywhere no matter how gently I dragged it, but sprinkling a little powder on the surface and pulling one comb line through kept the veins crisp. diffrent look though, more shimmer than solid white, so it depends what you're after.

For molds I used melamine coated shelf board with a bead of silicone caulk around the bottom, and everything released fine after a light coat of paste wax. Didn't trust plain wood forms after a friend's blank glued itself in. Also agree on the cure time. I wrapped mine after two days and the smell of not-fully-cured epoxy was still there when it was opened at the party. Embarrassing. A full weekend is the minimum I'd give it now.

Watch the corner rounding if any epoxy ends up on the edges. I chipped a corner out of one of the eight in my set doing a roundover on the router table, epoxy loves to flake right at the wood boundary. Now I sand the edges by hand up to 320 and stop, leaves a soft enough edge without the risk. Also curious what wood you used for the holder, I found anything too light made the white look yellowish next to it.

Shellac makes a good seal coat too, been using the stuff since before epoxy was on every hardware store shelf. One thin cut, dry for an hour, pour away. And on the mystery offcuts, watch walnut and anything dark, it'll bleed color into clear epoxy even sealed. I quit fighting it on one set and the amber tint ended up looking deliberate. One thing I keep wondering about, the white part. I made pour blanks back in the polyester resin days and every one of them went creamy within a couple years. Curious if these newer epoxies hold thier color any better, or if I'll be hearing about yellow veins in a decade.

Agree with the mica powder tip, it's what I ended up using too. I did a serving board last winter and sprinkled it over the white pour, then hit it once with a heat gun and the veins kind of bloomed on their own. Way less fussing than trying to swirl liquid tint. Only thing is it sticks to everything, dusted the inside of my gloves and it followed me around the shop for a week. For the holder I did mine on a small drill press with a forstner bit instead of a notch, gives a little cup for the stack to lean into.