: Lets see if I did this right: 9" diameter is a volume of 0.166 cubic
: feet, or a bouyancy of 10.33#. With two of them, that's about 20# of
: floatation. It seems to me you need about three times that much. Have you
: swamped with these?

Um, your point is good but your math is lacking.

V(sphere)=4 x pi x r^3 / 3 = 4 x 3.1416 x .375^3 / 3 = .221 cu ft

Density of water = 62.43 lb/cu ft

Buoyancy= (.221 cu ft) x (62.43 lb/cu ft) = 13.79 lb

Happy floating,
Porter