How dry does wood need to be before applying epoxy?

The wood must be fully dry before any epoxy goes on. Moisture left in the wood can interfere with adhesion and curing, and wood that has not fully acclimated can cup or bow after the top is sealed.

Check the slab with a moisture meter. The wood should be under 12% moisture content, ideally in the 8-10% range.

For freshly cut slabs, the general rule is to let the wood dry for at least 1 year for each inch of thickness before applying epoxy. Once the wood is sufficiently dried out, the cured epoxy will not have problems with wood movement after it bonds.

A sap streak in a pine slab may be nothing more than natural color variation in the grain, and on its own that is not usually a problem for the epoxy. The concern is whether the streak still holds excess moisture or resin if the slab has not dried properly. If any area feels sticky or tacky, seal the surface with 3 coats of an oil-based polyurethane before applying the epoxy so it bonds and cures properly.

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