Minimums and Maximums

[Andrew Baak]

Looking through the rules I could not find min, max for width at water line or max width or fin lengths? The only one I found was hull length? Am I missing something. Just looking before I start building.
Thank you.

[awallin]

Looking through the rules I could not find min, max for width at water line or max width or fin lengths? The only one I found was hull length? Am I missing something. Just looking before I start building.
Thank you.

There is no maximum width for the hull. Most boats are between 200 and 300 mm wide at the deck level.

The draught of the boat when in sailing condition should be 370-420 mm. The maximum draught of the hull is 60 mm.
There are no restrictions on fin width or length but the appendages may not project outboard of the hull.

For your first boat I would suggest building a tried and proven design.

[Andrew Baak]

Thank you for your Quick responce.
I found a triple crown plan that I will make. Could you tell me the average length of keels?

[awallin]

Thank you for your Quick responce.
I found a triple crown plan that I will make. Could you tell me the average length of keels?

If you mean the chord length measured along the centerline of the boat then a "small" parallell leading/trailing edge fin would be about 85 mm long. These have low wetted area but are harder to sail than bigger fins.
The Bantock boats usually have the biggest fins, the model I had on my Italiko is around 135mm long at the root and tapers to around 80mm at the lowest point. A big fin is easier to sail(tack, manouver) with but could have more drag due to larger wetted area.
The fin on my Cockatoo is 90mm at the root and 74mm just where it enters the bulb.

Fin thickness is very critical. Modern fins are around 6-7% thick which for a 85 mm chord fin means only about 5.1 mm