Mainsheet cleat on swivel base

[John_Clarke]

On my tiller steered Westerly Ocean 33 the cleat on the transom mainsheet is mounted on the block. This means that the cleating angle is only right when sitting at the aft end of the cockpit (with the sheet at right angles to the centreline of the boat). This is inconvenient and I would like to be able to work the mainsheet on a beat from the front of the cockpit where I can also winch the genoa sheets.

To solve this problem I am thinking of using a Spinlock Powercleat mounted on a swivel bracket like dinghies use (Fredriksen, Harken and Schaefer appear to make these for medium size yachts). The final block is attached to the pivot point of the swivel fitting. I plan to mount this fitting on a stainless steel right angle bracket on the aft face of the cockpit. The cleating angle should then be the same regardless of the position of the boom or where in the cockpit you are trimming the sheet - I hope!

Has anyone tried something like this or does anyone have any ideas about whether it might be successful.

John


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[chippie]

It sounds like it would work. There is however another way to achieve what you want (I think) .
It's hard to visualise technical issues with only a verbal description.

My boat has a camcleat arrangement where the mainsheet exits through a swivel block with the camcleat as part of this block fitting.All this is part of the mainsheet traveller assembly and althogh in front of where I normally am in the cockpit, can swivel to face wherever I am. A thumb through a Harken catalogue or the like should come up with something similar. I'm sorry I am not up with what a spinlock powercleat looks like, or am I already describing what you intend?
My boat is a 34' trimaran so the camcleat is handling reasonably substantial loads and can be quickly released with a sharp upwards jerk.

I hope I have correctly understood your problem and this is of some help.
Cheers

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[John_Clarke]

Thank you for your reply; it helps me to think about a solution. I agree that it is hard to visualise something technical without a picture. This is the swivel base I am thinking of using - http://harkenstore.com/uniface.urd/scpdinw1.ShowProd?B4RPMEB9Y958BG with the final block attached to it.

What I have a present is something like this - http://harkenstore.com/uniface.urd/scpdinw1.ShowProd?B4RPMEB9Y950JC but much poorer quality and it is attached to the traveller; from your description it sounds as if you have something similar. I think that a big problem I have is that the mainsheet slopes forward from the transom and is 30 degrees off the vertical when the boom is sheeted in tight. This means that as the block swivels the attached cleat can change from being inclined downwards to pointing upwards. I imagine that your mainsheet is nearly vertical when sheeted in hard and also in a trimaran you probably have a narrower cockpit and do not sit out on side decks to helm on a beat. It must be great to have a relatively level boat.

I have heard very good reports that the Spinlock PowerCleat is very easy to release and cleat under load- http://www.spinlock.co.uk/images/productImages/63.jpg .

Thanks again and happy sailing,

John


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[chippie]

The swivel bae you are considering is very similar to what I have, and yes it's great to be able to put a coffee cup down and have it there when I get back to it.

That Spinlock PowerCleat looks good, I may consider putting them in front of my sheet winches as I only have old fashioned rope jammers aft of them at the moment.

Cheers

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[Gezzer]

I have just changed my main sheet cleat to a powerlock, I kept the same block and simply modded the base plate to accept the powercleat, I did consider putting it onto a swivel base but I can generally reach my mainsheet from anywhere in the cockpit so not really needed. it works well, very easy to release in a hurry - just flick the rope.

Note - Spinlock advise against fitting them before a winch for jamming purposes, they cannot take the high loads that a main halyard can be subject to.

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[Strathglass]

The mechanism you are talking about is a larger version of what is used on many dinghies.

On some of them there is a mechanism for restricting the rotation to a smaller arc. This stops it from spinning round.

I have a 4/1 and 16/1 main sheet lines and have fitted a swiveling base to the 16/1 line. Both lines have spinlock power cleats.
This is on a 33ft yacht currently under construction.

Iain

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[John_Clarke]

Iain

Have you decided what make of swivel bracket to use? What type or class of boat are you building?

John

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[Strathglass]

John

The swivel cleat I am using is a Holt Allan one which is much like the Harken. It is mounted about 4 inches aft of the mainsail traveller track. It has a 16/1 advantage so the loads on it are not too high. It will enable be to play the main a little when sitting on the windward side. The swivel is set to rotate about 270 degrees maximum.

I think that I will have less loads than you as although the loa of our craft are the same my boom length is only ten feet and the main is about 180 square feet.

The boat I am building is is a Contention 33.
I bought the unused, decked hull with the keel and bulkheads fitted some time ago (something like 12 years)
I have been buying the bits and fitting it out as and when I could afford the expense, the time and when my domestic circumstances permitted.

I have tried to build it to the highest standards, everything is documented and I have receipts for most parts.
The hull was probably moulded in 77/78 and it was designed by Doug Peterson but has never been in the water.

It is a round bilged 3/4 ton hull with moderate beam (10' 5"), 33ft LOA, 28'6" LWL and the lead keel with 6' draft gives about 50% balast ratio. There is no skeg on the rudder and the transom is well drawn in. A bit like a Sigma 33 but with more ballast and taller masthead rig.

I have just collected the mast from the south.
See my recent posting on the Shuttlebut forum about the journey.

It is a Sparcraft F305 section, 15.85 metres long, purchased as a kit from Sailspar in Brightlingsea. It will be keel stepped with twin aft swept spreaders.

The kit is very comprehensive and includes the full deck collar, keel step, internal dam, internal wiring conduit, winch pad, kicker fitting, masking, rivets/plugs for all fittings, swivels for forestay/ backstay, tang backing plates, spreader end caps and lots of other bits. Everything is well labled and individually packed. I have lots of holes to drill as I chose the lowest cost package.

I could take a photo of the main sheet / swivel assembly when the rain stops and email it to you if you wish.

Iain

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[John_Clarke]

Iain

Thank you for your most detailled reply. You are right about me having greater loads to deal with; my mainsail is over 280 sq ft. I have just looked at the Holt website and think that their largest swivel base would be too light for my boat with a 5:1 purchase. When I get caught in a gust with the main pinned in the loads are quite high.

Your boatbuilding project is impressive; you have a great deal of patience and determination to keep at it for 12 years. Sounds like she should sail very well. If you have bought the mast I imagine you must be getting near to your launch date.

Good luck with the rest of the work and many happy hours of sailing.

Regards

John

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