The weight of the is still going to be a mystery !
Not necessarily if you have built a a scale model Ray. Extract from my 60th Anniversary Special Issue:
Scale Displacement
This sort of calculation can be even more impressive applied to scale models of larger craft, in smaller scales. A 4ft. long model of a Leander class frigate (2,200 tons displacement) for example, which would be 1/100th scale. True weight for such a model would be 1/100 x 1/100 x 1/100 x 2200 tons or a mere 51b! If it was not, and the hull lines were true scale, it would not float at the same waterline.
I have done a rough calculation on a TID which you might like to check:
Model length 42 inches Original vessel 65 feet approx scale 1:18
Actual displacement 124 tons, Using the formula above model displacement about 47.5lb which seems about right.
Colin