J-120 SoCal Fleet 4: Floatlines

J120 Float Measurement Instructions

1.) Mark the Stem Head Fitting

Place a measurement point/mark on the forward side of the stem head fitting. The mark should be placed at the intersection of the top of the hull flange and the stem head fitting. The top of the hull flange is the point where the deck becomes flat on the horizontal plane, and the round transition from the sides of the boat end.

2.) Measure to the water with a plumb bob on the bow.

Measure from the mark on the stem head fitting down 124.5 cm to the water with a plum bob. Please double check the length of the plum bob. The length of the line could shift, line can shrink, marks wear off etc. It is the owner's responsibility to insure the length of the line is correct.

3.) Mark the Stern.

The measurement point on the stern is the intersection of the transom and the bottom of the hull.

4.) Measure down to the water on the stern.

Measure from the mark on the stern down to the water with a plum bob 10.5 cm.

5.) Equalize weight.

Use the class equalization procedure to get the boat within "Float". Fill out the measurement certificate and keep it on the boat during One Design racing.

Tips for measuring

Float the boat when there is minimal movement in the water.
Attach the plumb bob to the bow and the plumb bob to the stern at the same time. Secure in place. Insure all people are off the boat to let the boat settle.
The boat will be"In Float" when the plum bob on the bow and the plumb bob on the stern are in the water 50% of the time or more.