Cunningham & Jib Halyard

Thread starter #1
The Capri 14.2 rigging diagram shows a pulley arrangement, called a Cunningham, to secure the jib halyard. My boat does not have this type of set up; the halyard is secured directly to a cleat. Is this common? What is the purpose of the Cunningham? Thanks.
 
Thread starter #3
Wavedancer: Thanks for your reply.

I found another mod 1 (1986) rigging diagram, one that is posted in this forum, which shows a Cunningham. It is deadended in the top of the gooseneck and passes through a grommet near the corner of the mainsail before going down to a cam cleat. There is a couple of things I find confusing. The corner of my mainsail has one grommet, which attaches it to the gooseneck end of the boom. My boom is setup so that the line hole in the gooseneck is facing downward. The rigging diagram shows that hole on top, deadending the Cunningham. This diagram identifies that pulley arrangement associated with the jib halyard to be "purchase on jib halyard". I don't have that purchase.
 
#4
The cunningham is used to put tension on the luff of the main to change sail shape. It ususally is done with a line through a grommet above the tack, with a line led up, through the grommet and cleated back on the mast. The same effect can essentially be achieved by a downhaul on the boom - a line is tied to the hole under the gooseneck and cleated below on the mast so that the boom slides up and down in the track. In both cases tensioning or easing the line changes sail shape. The block on the jib pendant allows you to put more tension on the luff of the jib to change sail shape. If you don't race, or aren't a freak about sail shape, then you probably don't need it. If you want it simply add a small block using the pendant measurement in the handbook to determine the proper point on the jib halyard at which to install it.
 

c14_Jim

Sailing on Shelter Bay
#5
A Cunningham hole is an eye at a short distance above the tack of the sail, which is used to adjust the tension on the luff. If you are not racing it has no point since you can simply pull the halyard tighter or lower the boom to tension the luff. However in racing there are limits to how long the luff can be (hence black bands on the mast) so a Cunningham is used to tension the luff instead. The halyard normally goes from the head of the sail through a sheave at the top of the mast and back down to a cleat (or winch) near the base of the mast. I have sailed on dozens of different classes of boats and not seen much different. Can you post the diagram you are talking about?
 

c14_Jim

Sailing on Shelter Bay
#6
Okay, I looked at the diagram. It might be confusing, but they show the halyard as going to tackle to give you mechanical advantage in tensioning the halyard. the Cunningham they have in the diagram shows one side of it, but it is just through the Cunningham hole and probably does the same thing on the other side or is dead-headed somewhere.
 
Thread starter #7
Page 16 of the handbook: http://www.sailingforums.com/C14_Handbook.pdf

The gooseneck has the opposite orientation as mine; it is installed on the boom with the hole at the bottom; this diagram shows the hole at the top of the goosneck. I have a rope dead-headed from the gooseneck, which I cleat to the mast near the mast base. It seems that cleating the gooseneck down is redundant to the boom vang.
 

c14_Jim

Sailing on Shelter Bay
#8
I'm confused. If the hole you are talking about is where the pin for the tack of the sail to be attached: it has to be on top of the goose-neck. In 43 years of sailing I don't recall anything different than that. The Cunningham is used to control luff tension so you can move the draft fore and aft. The Boom Vang has an entirely different function. The boom vang is used to tighten the leach when the mainsheet can not perform that function. Can you take a picture of your gooseneck with the sail on?
 

c14_Jim

Sailing on Shelter Bay
#10
Exactly. In the picture the boom is upside down. the slot for the sail is on the top of the boom. So when you turn it right side up the pin will be on top to attach the tack of the main sail into.
 
Thread starter #12
I am clear on that part. As you pointed out, the boom is upside down in my picture. So, the hole in the gooseneck (green line) is on the bottom when the boom is on the mast. The rigging diagram shows that hole on the gooseneck (green line) on the top and connected to a line that goes to the Cunningham. It seems the gooseneck (the part with the green line) is mounted upside down.
 
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