Can I pour another coat over epoxy that has already cured?

Yes. You can add another coat of UltraClear Bar & Table Top Epoxy over a cured coat whether it's been 72 hours or months. Within 4 to 6 hours of the previous pour no prep is needed, but once the epoxy has sat for more than 10 hours it has hardened and the surface must be lightly sanded and cleaned before you pour again:

1. Scuff the whole surface with 220 to 320 grit sandpaper. If you are fixing surface defects, start with a lower grit to sand the imperfections out, then work back up to 220 to 320. 2. Wipe the surface with a clean, lint-free rag and denatured alcohol or acetone. Do not use paint thinner or mineral spirits. Keep wiping until all sanding dust is gone. 3. Pour a new flood coat directly over it. Don't worry about the sanding scratches; the new coat fills them in and cures crystal clear again as long as you follow the correct mixing procedure.

The new flood coat will still self-level to 1/8". You can't thin it or brush on a thinner layer; it won't be smooth. If the first pour missed spots along the edge, you can sand and re-pour without a dam and let the epoxy run over the sides to coat them. If the first coat isn't dark enough, recoat with a Pigmently mica powder such as Dark Matter for an opaque color; liquid dyes stay translucent.

Bar & Table Top Epoxy instructions: https://cdn.shopify.com/s/files/1/0320/7168/0140/files/Epoxy-Instructions.pdf?v=1616443869