"Richard Riley" wrote in message
...
On Sun, 01 May 2005 03:00:55 GMT, "COLIN LAMB"
wrote:

:Cut the shape of the tank with a piece of balsa or other solid wood.
Then
lace it in a tub of water until submerged and measure the volume of
water
:displaced. If you have something like a laundry sink, it is pretty easy
:math.

Great idea. Cheaper with styrofoam.

He'll need to allow for a little less fuel, due to the volume of the tank
material;
but this is exactly the method I might have suggested if I had read the
question
earlier. A great additional benefit is that you end up with a model of the
tank
so that it will be much less likely to be built inverted--if there are
irregular
shapes.

Of course, _I_ would never make such an obvious mistake. ;-