Measure j80 headstay length

Ddean

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Does anyone know how the forestay  length of J80 is measured in order to compare it to the tuning guide of e.g North Sails which says 10.02 m? It says pin ( toggle bow) to pin(mast)  but does this length  include or exclude the toggle ( of 4 cm) at top of the mast as shown on the picture? ⁷
20210918-113720.jpg


 
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Rob

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Seems to me the different sailmaker tuning guides all state different lengths (even old vs new NS guide), makes me wonder how much it matters. You need a good setup/curve etc, no doubt, but maybe forestay length is not vital?

 

charis

New member
31
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It's vital for setting mast rake, but there should be enough play in the turnbuckle to make the adjustment.  I just installed a new mast and the measurement we used was 32' 10." pin to pin, which equated roughly to 32' 3.75" from the center of the head pin to the bottom of the threaded stud.  

As a note, I had to tighten up almost the whole turnbuckle to set my rake correctly.  This can vary based on deviations in construction and butt setting may affect it as well.

Sail fast! 

 

Stiffler's Mom

Anarchist
766
12
Seattle, WA
Center of pin. There are (2) ways to accurately measure. Pendulum swing from spinnaker halyard to gooseneck and forestay or main halyard from black band to center of transom. Or if the rig is down, the old fashioned way...

 
So after reading this thread I am not really sure if the question has been answered.  Do you measure  to the center of the attachment bar on the mast or to the center of the pin at the toggle?  Toggles can be different lengths.   I have also seen one guide that specifically shows to measure the the center of the attachment bar, not the toggle.   What is the consensus?

Brian

USA 1001

 

charis

New member
31
20
Brian,

  The rigger will measure pin to pin, but the only thing that matters for you is having enough room in your turnbuckles to set the mast rake.  To set rake you measure from the hounds to the transom and adjust the headstay.  I just adjusting mine last night, so the the topic is very fresh in my mind.

  North Sails has a great tuning guide that explains it well.

 
Brian,

  The rigger will measure pin to pin, but the only thing that matters for you is having enough room in your turnbuckles to set the mast rake.  To set rake you measure from the hounds to the transom and adjust the headstay.  I just adjusting mine last night, so the the topic is very fresh in my mind.

  North Sails has a great tuning guide that explains it well.
I agree that for replacement of a headstay, you can measure pin to pin and make the new one the same.   I also agree that the North and Quantum guides give a rake measurement which is controlled by , but there are a few guides that just give a headstay length measurement (not a rake measurement) for tuning.   The question then becomes does it them include the toggle or not.  I tend to think it should include the toggle.

 

El Borracho

Verified User
6,698
2,664
Pacific Rim
I’d make it the length that makes the boat sail the fastest. Which means, not snarky, that you may need to make a second forestay if the first try doesn’t work. Hulls and rigs are not made very accurately. And over time little changes may make a big difference. Like repairing the mast, swapping a toggle, hull distortion.  Regardless of numbers in a tuning guide I would make my rig look like the rig on the winningest boat. 

 
Hello 

Sparcraft confirmed to me that the 10020mm length is including the toggle. You can verify this if you back engineering the lengths of the foils and read the the Harken foil length cuts for the given forstay length. I hope it helps.

PS Harken AL00 Manual 

 
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