So, crunching the math presented here for late-comers.
40 cubic feet = 1 naval ton
25 naval tons = 1 cargo bay
25 ( 40 cubic feet ) = 1000 cubic feet.
The standard example would be 10ft x 10ft x 10ft ( or 2 by 2 by 2 on a 1-inch map )
However, any combination of measurements would be useful, say liquid-only cargo-bays are 5 x 5 x 40 ( 1 x 1 x 8 grids).
I took some grid-paper and made a simple guide to explain to my players the type of volume they're dealing with.
This also will help me layout a smaller ship ( instead of using one of the luxurious flip-map ships for their ship )
