Hunter 340 'A' rig measurement help pls

[markymac1961]

Hi All,
About to pull the trigger on a 'ASY' kite for my boat, and the sailmaker (Rolly Tasker Australia) requires 'A' measurement.
(Halyard exit box near top of mast to tack attach point.) All the H340 rig specs I can find online have every measurement but 'A'.

This may be individual boat specific as mast rake etc can be adjusted, which would effect 'A'. The boat, as recently purchased by me, does not at this stage have a kite halyard... so factory spec length for that would be helpful too. I've attached pics below fyi. Cheers and regards, Mark Mac - 'Malua'

 

[jssailem]

All the H340 rig specs I can find online have every measurement but 'A'.

That is because you are sailing a fractional rig.
You have three options.

1. Break out that Geometry book you read in high school and learn the Pythagorean theorem.
   1. a^2 + b^2 = c^2. A = distance from mast base to bow hard point. B = distance from mast base to hard point at mast top. C = the hypotenuse. This is the length that you want.
2. Or you can use a halyard (ideally the spinnaker halyard you intend to use) to run to the mast top, attach a messenger line, and attach a long tape measure to the line. Stretch the messenger line and the tape to the point on the bow where you intend to attach the sail's tack.
3. Ask the internet and pray that the answer matches your boat's dimensions.

Easy Peasy.

 

[shemandr]

Rolly Tasker Australia may measure it assuming they are local. Or they may have someone local , like a rigger, who has the skills. If I were in that business I would want to do my measurements rather than depend on a customer's skill or lack thereof. I would not at all want to use a published number. I would think adjustments would be way too expensive and stressful to allow them to happen.
There is more flexibility for an asymmetric spinnaker than other sails because the tack normally floats and the luff isn't attached to the forestay. Nevertheless there are times when you'll want to carry the sail closer to the wind and if the luff is too long you will be frustrated with the performance.

 

[markymac1961]

That is because you are sailing a fractional rig.
You have three options.

1. Break out that Geometry book you read in high school and learn the Pythagorean theorem.
   1. a^2 + b^2 = c^2. A = distance from mast base to bow hard point. B = distance from mast base to hard point at mast top. C = the hypotenuse. This is the length that you want.
2. Or you can use a halyard (ideally the spinnaker halyard you intend to use) to run to the mast top, attach a messenger line, and attach a long tape measure to the line. Stretch the messenger line and the tape to the point on the bow where you intend to attach the sail's tack.
3. Ask the internet and pray that the answer matches your boat's dimensions.

Easy Peasy.

Thank you 'jssailem' for reminding me of how much I struggled with Maths in school... especially when they started throwing letters in amongst the numbers - cruelly confusing me even more! (And unfortunately when all the other kids in class were reading their Geometry books... I was probably reading a comic under the desk)

I LOVE option 2... which is what I'll be going with. I'll be shimmying up the stick anyway running the new halyard... so dead easy to throw a tape and 'messenger line' in the bucket as well - hitched to the tack point first. Thanks for your input mate all the best. Mark Mac - 'Malua' - QLD Australia

 

[markymac1961]

Rolly Tasker Australia may measure it assuming they are local. Or they may have someone local , like a rigger, who has the skills. If I were in that business I would want to do my measurements rather than depend on a customer's skill or lack thereof. I would not at all want to use a published number. I would think adjustments would be way too expensive and stressful to allow them to happen.
There is more flexibility for an asymmetric spinnaker than other sails because the tack normally floats and the luff isn't attached to the forestay. Nevertheless there are times when you'll want to carry the sail closer to the wind and if the luff is too long you will be frustrated with the performance.

Thanks for the tips mate.
This measurement is apparently pretty critical as the flexible 'torsion stay' which is integral to the top down furler system, has the be 'tensioned' (exact correct fixed length) to function properly. I'm going to take tape measures up the mast, and short of a bit of 'tremble variance' coz I'm scared of heights.... should be able to get the correct length down to within a couple of mm (Or as we say Down Under... within a 'Bee's Dick.')
All the best and cheers for chiming in - Mark Mac 'Malua' QLD Australia

 

[Boiler]

Sailboat data, may have in a convoluted way have what you are looking for. They have the I J P E lengths.

HUNTER 340 - sailboatdata

Deep Keel: 6.0′.

sailboatdata.com