Waterline on TT board

[downunder]

Gents,

I've checked my TT boards. On North Jamie there are two water lines in one direction:

1)

2)

Placing a ruler trough the middle on similar angle is showing a slight concave on tips. More concave on tips with lower angle.

My boards two lines as well:

1)

2)

I think I'm riding #1) quite flat, meaning a front fin is almost touching water (4mm concave, 1/3 length, board 120cm). I do not ride north.

Thoughts? Conclusion?

[rynhardt]

I would expect the waterline to have a fairly small angle from the centreline of the board, maybe 20 - 30 deg - your ruler is sitting at about 60 - 70 deg.

And all of these measurements do not include the weight of the rider, which will flatten the rocker somewhat. Like you said, I don't know how much of this is applicable to a TT which flexes.

On a surfboard I would expect the board shape to remain fairly static.