[Capri25] Jib Cunningham Specs

[Dan McNamara]

Jim,

The boat is in a barn 50 miles away, so i can't take pictures.   From  
my memory ours consists of:

12 to 1 cascade:

1.  A hook for the cunningham grommet.
2.  A small block attached to the hook.
3.  A small block aft of the tack shackle on the bow of the boat.
4.  A small block with a becket or open shiv to run the Spectra or  
Dynema to and through
5.  A small fixed block anchored to the foredeck at-least 2 feet from  
the bow.
6.  A medium block sufficient for a 3/8" or bigger sheet.

About 6 feet of Spectra or Dynema (no cover 1/4" or less).  This runs  
through the small blocks.
12-16 feet of 3/8" or bigger sheet. (an old spin sheet works fine).

For simplicity I will your thin coverless line as Spectra.  But any  
high tech low-stretch line will work but the the more slippery the  
better.  UV resistance is a factor too.

With the Spectra tie a small bowline to the base of your forestay  
turnbuckle.
Run the other end through the small block attached to the hook for the  
Grommet (1,2).
Then Run the same end through the small block aft of the tack shackle  
(3).
Cut this Spectra Line long enough so that the hook for the cunningham  
grommet is slightly higher then your highest cunningham grommet and  
you have enough to tie another bowline.
Tie the end of the Spectra to a small block (4).

With another piece of Spectra tie a bowline to the becket or open shiv  
of block (4).
Run the Spectra through the fixed block anchored to the foredeck at- 
least 2 feet from the bow (5).  How far back from the bow you mount  
the block depends on how high the cunningham grommet is on your sail.   
The higher the farther back it needs to be mounted.  If you mount it  
to close to the bow you will not get enough purchase.
Run the Spectra through block (4).
Tie the end of the Spectra to the medium block (6) with a bowline.   
Trim this segment of Spectra so that it is just long enough so that  
block (6) is as close to block (4) when hook (1,2) is in its highest  
position.

  Run the sheet trough the base of the forward stantion and tie a  
stopper knot.
Run the other end of the Sheet through block 6.
Run the sheet through the base of the other forward stantion and tie a  
stopper knot.

Now when you are on the rail you can the sheet and have a 12 to 1  
effect on the cunningham hook.

I would suggest using some cheep line get the lengths you need before  
you cut up a bunch of Spectra or sheets.


I am not the best artist but If you need I will try a draw it for you.

If you do not want to mount a block to your foredeck (drill holes).  I  
have an idea for a 8 to 1 cascade that does not need any drilling.

Let me know,

Dan









On Dec 31, 2008, at 8:55 AM, James Stark wrote:

In the Backstay topic there was some discussion regarding a jib  
cunningham.  I lack one of these, but will consider adding one.  Can  
anyone provide me some specifics on setup?  Pics would be GREAT!

Email to SailCO26 at Yahoo.com is fine...

TIA!
Jim



Three old guys are out walking. First one says, "Windy, isn't it?"
Second one says, "No, its Thursday!" Third one says, "So am I. Let's  
go get a beer."


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