I want to shape a board using EPS and epoxy. I have been told that EPS is much more buoyant than polyurethane–compared to a PU blank of the same size, how much eps could I lose and still have the same buoyancy?

1.9 - 2 lb. foam 6/6 deck 6 bottom 1/8". Although US has had some fabulous 2 lb. eps lately can go 6/4 on the deck no problem.

Okay, EPS is lighter per cubic whatever than polyurethane foam. Neat. The thing is, in the overall board plus rider unit, it’s meaningless. if the board alone has a volume of X liters or Y cubic feet and it weighs Z pounds or kilos, add together your weight and the weight of the board and what difference does it make? The board will still float you pretty much the same.

Example - figure you weigh in at 165 lbs. The board has a volume of 3 cubic feet. Urethane foam weighs 4 lbs ( picking numbers out of nowhere) per cubic foot, the EPS is 2 lbs per cubic foot. Weight of board difference, six pounds ( and that’s a huge board). Percentage difference for you plus the board, on the order of 4%, thus meaningless.

Buoyancy- again, board **plus **rider, the bouyancy difference is meaningless. kinda like the difference in how you float the board before or after a good lunch,. So, shape it the same. You’ll be fine

doc… iconoclast to the last

Thanks!

doc is 100% correct!

The difference between EPS and PU is not noticable in the bouyancy.