epoxy may need a primer surfacer to cover imperfections, but it doesn't need a sealer - the "important" prep is that the epoxy or other primer is smooth, if the epoxy is smooth enough to satisfy you for top coating [even with house paint grin ], nothing else is needed

Bill

Moved over to the Passing Lane

"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir
"When we tug a single thing on an old truck, we find it falls off" ~ me
Some TF series details & TF heater pics