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lenswim
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Joined: Fri September 3rd, 2010, 10:37 am

balance

Postby lenswim » Fri September 3rd, 2010, 11:35 am

Hi,
can anyone help? I am looking for a set of lone gull II plans. I would like to check the designed water line, mast rake, sheeting arrangements and etc. I am trying to fathom out why my boat carries weather helm but the original did not.
many thanks Len

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Fiddler's Green
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Joined: Wed March 1st, 2006, 12:58 pm
Location: Essex
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Re: balance

Postby Fiddler's Green » Sat January 15th, 2011, 1:46 pm

Sadly We have had no luck on these either.... But we keep asking!

John
Proud owner and builder of 'Fiddler's Green'

GHM
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Joined: Thu March 10th, 2011, 9:36 pm

Re: balance

Postby GHM » Fri March 11th, 2011, 1:35 pm

Hi,

I'm only generally familiar with Lone Gull, but over 35 years with GH's including 9 building them I played around with all sorts of things to reduce the weather helm I often had on my first and subsequent boats. Sometimes it could nearly pull your arms out of the sockets! In the end I could always helm with two fingers on the helm even when she was over pressed, although that was with a light airs cutter, as opposed to the standard sloop - but with some other significant changes.

Initially I tried the oft written advice of changing mast rake and ballast distribution. I never really noticed a definite improvement, whatever I did and I put this down to the boat being very insensitive to both because of the long keel and the heavy displacement.

With my first, standard sloop rig, Terry Erskine hull, I then talked to a sailmaker who recommended a large overlapping genoa which was sheeted on the stern quarter with the sheet brought forward to the winch. In certain conditions it worked quite well but in a significant blow it had to come down of course.

I began to wonder if I could reduce the helm loads by looking at the rudder and eventually this proved very effective, vastly improved manouvring under power and decreased the powered turning circle to about half. (verified in Poole harbour with an unmodified GH as we both turned together).

I don't know whether the Lone Gull has a semi-balanced rudder or not and I don't want to bore you with masses of unnecessary detail. But if it hasn't, its very well worth considering and probably relatively easy and cheap to do. If you're interested I can go into detail, although it's a lot simpler with a few diagrams!
Mark.

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Fiddler's Green
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Re: balance

Postby Fiddler's Green » Fri March 11th, 2011, 4:52 pm

Weather helm is a feature of all of MG's designs, he admited to me he was overly cautious not to build a boat with lee helm tendencies.

The Eventide has, over 50 years of evolution, cured the problem.

We first took all the rake out of the mast, on the original drawings the boats were akin to Arab Dhows!

Then we ensure the mast is correctly set up with a slight bend in the mast, in the middle forwards, to the extent of half the fore and aft diameter of the mast. Whan sailing this is negated by stay tension and the mast becomes upright.

We further experimented and found simply moving the centre of effort of the sails forward helped, so later designs featured a bowsprit. (Most also had a Staysail, with cutter rig. this helps set the bend into the mast as well....)

To help even further Maurice later extended the keel/deadwood aft to meet the rudder, as experiments had indeed shown this was even more helpful than moving sail area forward. We also found extending the bilge keels aft helped and we also realised that moving the bilge plates a foot aft worked!

The keel eventually extended aft to the transom hung rudder alteration he added. On our boat the turning circle under power is still 1 & 1/4 boats length... Full length keel and transom hung rudder.

The rudder can be semi balanced, this however will slow the boat slightly, although it will relieve the weight from the helm, it does not cure the weatherhelm it self. The early Steel plate rudders were semi balanced flat plate. Not very hydrodynamic. Today we strongly advise rudders built as the one on Fiddler's Green, like two aeroplane wings back to back with rounded entry and very fne 1/4" trailing edge.

The modern Eventide has 1 finger of weather helm in gentle brezes, If you let go she will gently round up. And still never any lee helm.... (You should be able to tack to windward under genoa alone and sail a figure of 8 too. In light airs and calm water FG can.)

I use 3 fingers up to F4, and at 5 a gentle hand. At that stage we are reducing sail and reefing the main maybe more than the Genoa. In a 6, rolled Genoa and use staysail, unless you are a racer, and 3 reefs in the main. I am a prudent sailor, but have been out in worse, with the right crew, the weather helm was always present but never excessive. If you are hanging on to the helm and bracing yourself you need to read the suggestions on the Hints and Tips pages. all of this mentioned here is explained in depth.

I spend a long time every spring getting the mast set up just right, sadly I have seen some curious bends in masts, the wrong way! A Baggy main or a bendy mast to induce bag, will just make the boat heel and the further it heels the more the hull shape will incuse weather helm, flat cut and set sails reefed early to keep the boat more upright will lessen the effect.

Hope all this ramble helps, but look at the main site for loads more...

John
Proud owner and builder of 'Fiddler's Green'


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