
Don’t worry about removing this length from your previous measurement we will do that for you. This is so we can remove the length from our previous measurement. Next thing you’re going to do is measure the length of your halyard shackle and knot. Measure it a second time, just to make sure that you got the right measurements.

Try to get this measurement nice and straight. To see a diagram of a boats rig spec and how we define them visit this page. This is your P measurement, or the maximum length that the luff of the sail can be. What you’re going to do is measure along your mast, from where the halyard enters the shiv to where your boom connects your mast, the goose neck. It’s almost easier than when the mast is up because all you have to do is run the measuring tape along the mast. The first thing you’re going to do is measure max hoist with the mast down.

The video outlining this process is below. This process is super simple and shouldn’t take too long at all.
