Measuring luff an old sail

[dave777]

The genoa gets tightened when it's on the furler, so how do we get an accurate measure of its luff when its a big sail in your backyard?

Do we measure from the load bearing surfaces on the sail, the outermost portion of the sail fabric, or the maximum distance of all material?

[Weyalan]

Drive a solid peg into your lawn and hook the tack over the peg. Pull on the head (or clew) when measuring... that ought to be close enough. If you are so close to the max luff length that your furler will take that measuring stretch is a factor, the sail is too big.

[sestina]

You can't. Measure the boat instead. This is why most rig measurements for rating are taken on the boat, I, P, E etc.

[barnakiel]

I would measure the boat too: hoist a long measuring tape in place of the sail and that is that.

Do not build a sail that is a tad too long, better one that is a tad too short.

b.

[boatman61]

Wot b sed... measure on the rig..

[dave777]

Thanks all for the suggestions.