Do I need to lacquer copper or brass before applying epoxy?

Copper, yes. Brass and most other metals, no.

UltraClear Bar & Table Top Epoxy can be applied over copper sheet and copper bar tops, but seal the copper with one coat of copper lacquer first and let it dry before pouring the epoxy. Lacquering is a requirement specific to copper; brass and most other metal surfaces don't need it. The same rule applies to UltraClear Deep Pour Epoxy.

You do not need an epoxy seal coat on copper. The brushed-on seal coat is only for porous surfaces such as wood or concrete; copper is non-porous, so once it is lacquered and clean, pour the flood coat by itself and let it self-level to 1/8 inch. Seal coat only wood edges or trim the epoxy will touch.

For coverage, a 32 sq. ft. copper bar top with a raised edge takes 3 Gallons Combined; order 4 Gallons Combined if the epoxy will flow over the sides, to allow for the loss over the edges. Use the coverage calculator for other sizes.

For an outdoor copper table, the epoxy is designed to withstand UV exposure and customers have used it outdoors in indirect sunlight, but no resin is immune to sun damage over time. Lacquer the copper as usual, and once the epoxy has cured, spray on a coat of UV polyurethane to further slow sun damage.

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