20170318

Mast Position

Reconsidered the mast position. The mast position determines many other decisions so we need to get this right.

The center of effort of the sail is 110cm aft of the luff and 90cm aft of the forward end of the mast foot. If we put the mast bulkhead at 120cm, CE will be at 210cm. This increases the size of the bow tank and allows a mast bury of about 36cm.

CLR should now be at 210cm minus a few cm to provide some weather helm. Let us say 205cm. The daggerboard will have a chord of 35cm and run from 187cm to 222cm. The daggerboard case runs between 180cm and 230cm. The extra length allows a robust construction and provides room to shift the position of the board if needed.

The thwart will run from 260cm to 290cm. This leaves 130cm to the aft bulkhead at 390cm. The floorboards should be about 5cm from the bottom.

The aft tank will fit a folded sea chart.