Adding a cunningham

[Jake]

I have a Bav 44 with a Selden mast.  My original Elvstrom main has a cringle for a cunningham, but it appears that there has never been one installed.  I would like to install one.  I may or may not run it back to the cockpit.  My first thought is just a 4:1 tackle that is anchored on the side of the mast below the boom.  I'm sure others have added one.  Anyone with any experience like this?

Jake

[kavok]

My solution. Selden mast has dedicate holes for a 2:1 system that I drive at a stopper.
Easy to use.
The blu and red line.

[IslandAlchemy]

Why not just use halyard tension?  I don't see why you would want the extra complication of a cunno.

[kavok]

A Cunningham is an adjustment line used to increase the performance of the mainsail by changing its shape.

Basically, it is a rope that acts as a downhaul, which is often connected to a cringle in the luff of the mainsail between the tack and first reef point.

It is used to increase luff tension by pulling the luff down which changes the draft of the sail, bringing it forward or aft. It is hard to get the same amount of tension on the luff using the main halyard alone, as it is a straight pull onto a winch therefore the Cunningham line was invented.

The Cunningham can be set up as a four, six or eight to one purchase so that the luff tension can be tweaked depending how serious you want to be. The Cunningham in the first instance is good for getting creases out of the luff. The next use is to fine tune the depth of the sail when sail trimming.

Using the Cunningham will always leave a little bag on the foot of the sail however try to remember the following: 

Increase tension for strong winds and rough seas
Decrease tension for light winds in flat seas
 

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[IslandAlchemy]

I know what a cunno is for, but it is used then the halliard is locked-off and cannot be adjusted under sail.

When you can adjust the halliard tension under sail, you have no need for a cunno as they both do the same thing (increase or decrease the luff tension).

[kavok]

The efforts are very different. Cunningham is easy to operate.

[Mirror45184]

Main halyard also works against the weight of the sail too. As Kavok also said in one of the posts, the cunningham can have more more purchase put into it for ease of adjustment.
@Kavok I like the use of a Friction Ring instead of a turning block!

[kavok]

Yes you are right, Chunningam is very short rope so has much less elasticity of the halyard.
Chunningam also modified  the low shape of the main.
Rings are very useful for a lot things on  the boat.
This is to correct route gennaker tack

[Ailatan]

Hi Kavok,
Judging by the quality and the number of deck organizers that you have I was wondering how have you solved the rope clutches issue.
Could you please share a picture of them?
I also would like to know if it was difficult to change the deck organiser.

[kavok]

Deck organizers, simply buy the same Rutgerson organizers and mount it using more long bolts.
I have not clutches problems, I simply add 3 ANTAL clutches for every side. But I moved all the clutch so I did new  thread holes. The last clutch remain out of the aluminum counterplate, so I used bolts and nuts.

[Ailatan]

Hi Kavok,
Thank you for sharing the pictures with us. Very interesting deck layout.
Regarding the Antal clutches, do you find any difference as compared with Rutgerson? I see that the handles are made out of aluminium, so no problems with the U.V.

[kavok]

Antal and Spilock are the best for my opinion. Antal use a system nominatet V Grip.
Lever are inox. The little measure(6 to 12) is no good for 12 mm rope, but I am changing all 12 mm lines with 10 mm Dyneema Gottifredi Softech.