Hi PD's ......calculating the displacement [

not weight] of the model prior to manufacture is not difficult

1) go to the green grocer....select three empty polysterene brocilli boxs & tak'em home for FREE
2) cut into 300 mm long x 50 mm wall thickness x the beam [width] of planned vessel
3) laminate with contact glue sufficient layers to a keel level to deck level height
4) roughly sand the bilge keel radius to both sides
5) scribe a TEXTA line of the proposed water line
5) take to the test tank [bath] & place the kitchen or bathroom scales & exert a downward force to equal the dispalcement @ water line...record this value [in kg's]
= result 1Repeat steps 1), 2) & 3)
6) roughly sand the next 300 mm long section to represent the bow section
Repeat steps 5) & 6)
= result 2Repeat steps 5) & 6)
7) Same applys for an AFT sanded section...
= result 3So if the 1:48 model of Glen Sannox was 1700 mm long.....the confirmed displacement would =
Total displacement = result 3 + result 2 + [the middle bits ....or 3.66 times the weight of result 1]This is totally true & so simply effective as we consider only displacement... not weight of materials