Measurements & numbers
P, E, I and J
The four letters that describe your rig — and the first thing any sailmaker asks for.
P — mainsail luff length: the usable height of the mast track, from the boom to the top black band.
E — mainsail foot length: along the boom, from the mast to the outer black band.
I — foretriangle height: from the deck up to the forestay attachment.
J — foretriangle base: from the front of the mast to the forestay at deck level.
P and E size your mainsail. I and J size your headsail — and J is the divisor behind that "150%" figure (see LP).
They are usually published for your boat, and our Boat Finder holds them for over a thousand production models. But published figures describe the boat as drawn, not as it stands in your marina today — which is why we confirm against real measurements before cutting. See measure your boat.