>> Some club mates of mine are looking at possibly building a rowing tank, and are trying to establish dimensions for it. They have got figures for most numbers and adjustment ranges they'll need for the rig, however they've been stumped by what the difference in height between the seat and the water level should be. Is there are hard and fast rule for this? I imagine in a boat this will vary depending on how the crew weight is in comparison to the weight the boat was built for, but presumably there should be a rough range for this measurement. If anyone can help out on rough numbers for this, that would be great!
> I keep forgetting to measure in the morning since you asked a couple
> days ago. there's a couple inch range from different boats, but my
> eyeball guess is 6-7 inches.
Deliberately working from memory -
A typical 8+:
Waterline is about level with slide-beds.
Slide-beds ~190mm below sax tops.
Seats (lowest contact point on top) ~120mm below sax tops (here
considering conventionally-rigged shells, whose free-board significantly
exceeds that of the cut-down, & thus much wetter, wing-rigged jobs).
Oarlocks ~175mm above seats.
Gives you these values:
Seats ~70mm above waterline
Oarlocks ~245mm above waterline
All very much 'ball-park' stuff
Then go to a 1x:
Seat ~100mm above waterline
Oarlocks ~175mm above seat
So oarlocks ~275mm above waterline
With a single you're constrained by the shallowness of the hull - feet
mustn't go through the bottom! Which helps explain the differences seen
above. And then there's the popular doctrine demanding a large
seat/feet height differential - "So you can get your weight over your
feet at the catch", goes the somewhat irrational mantra.
And from time to time I get folk trying to prescribe oarlock-to-water,
seat-to-feet & seat-to-oarlock differentials, having read this from some
book without understanding the inherent constraints imposed by the
realities of boats.
Carl Douglas Racing Shells -
Fine Small-Boats/AeRoWing Low-drag Riggers/Advanced Accessories
Write: Harris Boatyard, Laleham Reach, Chertsey KT16 8RP, UK