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How do you tell what size genoa is on the boat? Mine is on an auto-furler, and when fully deployed and cranked as tight as makes sense it comes to the SS railing where the life-line "pelican" hooks up...on this boat that is at the forward end of the cockpit.

Thanks.

Sounds like you have a 150. Genoas are guaged as to how much of the main they "cover up". I.E. if the sail covers 10% of the main it is a 110, half the main would be 150.

Hope this helps,
Azzarac

Sounds like a 150% genoa.

Measure from furler drum to mast, then measure the foot of your sail. Divide the foot of the sail by the distance from the furler to mast and you'll get your size as a percentage.

example: foot of sail 15ft/furler drum to mast 10ft= 150%

Hope this helps

Willy

Willy and Azzarac.... I hope you'll excuse me for correcting your sailmaker's geometry It's close, but not correct.

It's not the length of the foot that matters. It's the "LP", expressed as a percent of the rig dimension "J".

J is the horizontal distance from the forestay to the front face of the mast, measured perpendicular to the mast.

LP stands for "length perpendicular", and is the distance from the forestay to the clew of the sail, measured perpendicular to the forestay.

%LP= LP divided by J

The foot length of a 100% sail will vary depending on how high the clew is. A high clew'd sail has a longer foot than a low clew'd sail.

If you draw it out, you'll see that a 100% jib always overlaps the mast. The higher the clew is, the more it overlaps the mast.

We use the same genoa for the 26X as we do for the 26M. In the drawing below, the LP is 14' 8".
The M and the X have very slightly different J measurements... the M is 9'8", and the X is 10'5"
So.... if you do the math....
The genoa on the M is a 151%
The genoa on the X is a 146%

.... but that's close enough to call both of them 150% Genoas !



Fair winds,
Judy

Thanks, Judy, for setting the record straight with your informative post. Too often one can be led astray by mis-information (posted with good intentions) on internet forums.

Judy B wrote:The M and the X have very slightly different J measurements... the M is 9'8", and the X is 10'5"
So.... if you do the math....
The genoa on the M is a 151%
The genoa on the X is a 146%

Not to be picky, but I believe the J dimension of an X is 10.08 ft, not 10.42 ft. That also makes the math work out to 146% using the LP distance you gave.

Thanks to all for the help....I'm goin with 150 until I am so bored (and have a measuring tape) that I do the actual figgurin

...everyone change the 150 in your profiles to a 146...

I hate it when there is inaccurate information on the internet...

Mine too - it's a 150% Genoa.

coolchange wrote:How do you tell what size genoa is on the boat? Mine is on an auto-furler, and when fully deployed and cranked as tight as makes sense it comes to the SS railing where the life-line "pelican" hooks up...on this boat that is at the forward end of the cockpit.

Thanks.

tkanzler wrote:

Judy B wrote:The M and the X have very slightly different J measurements... the M is 9'8", and the X is 10'5"
So.... if you do the math....
The genoa on the M is a 151%
The genoa on the X is a 146%

Not to be picky, but I believe the J dimension of an X is 10.08 ft, not 10.42 ft. That also makes the math work out to 146% using the LP distance you gave.

Right you are. My bad.
I must have misread something in my database. and then did the math based on that.