cunningham

[TiggerToo]

What is a cunningham for? Why doesn't hardening up the halyard have the same effect?

 

[Seajet]

The cunningham is more usually fitted on dinghy or keelboat mainsails, where it will tension the luff and flatten the forward part of the sail, hopefully in conjunction with a tensioned clew outhaul; yes on larger boats with winches the halliard is usually tensioned, boom pulled down on its' track and / or a flattening reef put in.

 

[sailorman]

You forgot to mention "Black Bands"

the sail is stretched up to the black band (ie the max measured hoist allowed) any further stretching to reduce the sail camber is then downwards via the cunningham hole. this happens on all plain sail
Im sorry i cant remember Mr Cunninghams christian name who invented this rule bend
http://www.wayfarer-international.org/WIT/race.related/RiggingTips/UncleAl/Cunningham/Cunningham.htm

The cunningham is more usually fitted on dinghy or keelboat mainsails, where it will tension the luff and flatten the forward part of the sail, hopefully in conjunction with a tensioned clew outhaul; yes on larger boats with winches the halliard is usually tensioned, boom pulled down on its' track and / or a flattening reef put in.

 

[boguing]

Friction in the turning blocks and sheaves and internal friction in the rope mean that a direct pull is easier.

 

[Woodlouse]

Mast tracks are not always friction free and simply wanging on the main halyard won't necessarily tighten the luff evenly. The cunningham is to provide luff tension at the tack.

Contrary to what Seajet says, any boat rigged with an eye towards performance will have a cunningham, or the means to rig one regardless of size.

 

[bedouin]

You can usually adjust the cunningham as you would the kicker - so you can tweak it regularly while the sail is powered up. To achieve the same with the halyard you would usually need to de-power the sail, release the kicker, slacken the mainsheet, put on the topping lift and so on. A lot more work and you cannot see the impact immediately.

 

[PeteCooper]

Tightening the halyard flattens the sail, moves the draft forward and closes the leech.
Tightening the cunningham flattens the sail, moves the draft forward and opens the leech.
I am not sure if flattening reefs are still used - I thought that they were out of fashion these days?

 

[claymore]

You forgot to mention "Black Bands"

the sail is stretched up to the black band (ie the max measured hoist allowed) any further stretching to reduce the sail camber is then downwards via the cunningham hole. this happens on all plain sail
Im sorry i cant remember Mr Cunninghams christian name who invented this rule bend
http://www.wayfarer-international.org/WIT/race.related/RiggingTips/UncleAl/Cunningham/Cunningham.htm

Briggs Cunningham

 

[sailorman]

He knew about "Black Bands"

Briggs Cunningham

 

[lw395]

The cunningham does not fight the leech tension, so it is much easier to adjust than the halyard.
That makes it independent of the kicker and sheet, making it a more practical control.
If you have the eye in the sail, find some spare blocks and give it a go.

 

[Houleaux]

That's really useful info. I'd thought the same as the OP, but all the stuff about leech tension and friction in the mast track makes perfect sense. To my shame I've never bothered adjusting the cunningham on my boat. I will now though!!

 

[Sgeir]

Friction in the turning blocks and sheaves and internal friction in the rope mean that a direct pull is easier.

Spot on. For us, fitting a Cunningham has been about the simplest yet most effective alteration to sail management. Much easier to get the shape you want.

 

[TiggerToo]

many thanks for these very useful posts. I see the point now.

Next on the agenda will be trying to sort out how to rig the thing on Tigger... can't wait to try

 

[sailorman]

Check-out black bands here

many thanks for these very useful posts. I see the point now.

Next on the agenda will be trying to sort out how to rig the thing on Tigger... can't wait to try

http://www.epsails.com/mainsail_measurement_instruction.htm

 

[Sgeir]

http://www.epsails.com/mainsail_measurement_instruction.htm

No mention, I see, of the snurble grip-thribley. Does anyone still use them?

 

[Woodlouse]

No mention, I see, of the snurble grip-thribley. Does anyone still use them?

Yes, but only for attaching aeroplane wings.

 

[Grumpybear]

Yes, but only for attaching aeroplane wings.

What part of the boat do you attach them to?

 

[Woodlouse]

What part of the boat do you attach them to?

Just under the wheels.

 

[Grumpybear]

Just under the wheels.

Thanks. In retrospect, that is obvious.

 

[sailorman]

It enables one to steer from below the spindle, you then think you have a tiller

Thanks. In retrospect, that is obvious.