Archimedes found: If the object is less dense than water (if it floats on water), it
displaces a weight ( = volume ) of water equal to the weight of the object. If the
object sinks in water, it simply displaces a volume of water equal to the
volume of the object. ( 1 liter of water weighs 1 kg )
OC 1 are designed for paddlers that weigh about ~180 lbs. The boat itself including ama/iakos weighs ~ 30 lbs.
The total weight is ~ 210 lbs. The boat will sink accordingly and float at the 'designed waterline'.
If you place more weight on the boat it will sink deeper = sinkage. The sinkage depends on the design and is different for each design.
An experienced boat designer's response:
"Weight is difficult to design for without compromise.
Example: A boat is designed for ~ 90 Kg ( boat and paddler ). In this design an added ~ 14 kg would cause 1 cm more draft, thus the entire boat would sit 1/2 inch deeper in the water.
That will probably not be too much of a performance difference, but in general terms I think that boats can only tolerate ~ 10-15kg + without performance loss.
It would be optimal to have 2-3 sizes of the same design to serve the paddlers best.
Competition kayaks and canoes have sizes for every 8-10 kg, S,M ,L ,XL (some even in SM ,ML,L,XL,XXL) as you can optimize the volume and reduce drag for that specific weight.
Some manufacturers state a boats 'preferred paddler weight' from 60-90 kg or 50-100 kg. ( 1 kg = 2.2 lbs ).
This does not make much sense:
The volume difference needed for these weights is 30-50 liters in the underwater hull and ca 60-100 liter overall boat volume . ( 1 gal = 3.784 liters )
The main problem/reason is, that most boats are hand designed. Therefor it is almost impossible to scale to certain weights.
A less weight sensitive boat is designed flatter so that the bow and stern are more in the water. That way a lighter paddler paddle won't lose the length.
For heavier paddlers rockered boats are better due to the rapid increase of volume with added weight, less wetted surface is induced that way.
For 60-70 kg paddlers the performance gain of a smaller boat would be much bigger than is the loss for bigger paddlers.
By adjusting the design this way for the middle weight paddler (70-75kg) you end up having 2 boats, a boat for flats and a big wave."
OC 1 design should be optimized for weight. To have one single design for all weights limits the performance of the athletes.
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