Swing keel question

TQA

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I have a New Bombay Trading Company Explorer 44. It has a swing keel which increases the draft from 5"6' to about 9"6'.

The keel is operated from the deck by a wire winch.

My question is what angle should I drop the keel to? I had always assumed that it should swing through 90 degrees, basically hanging straight down from the pivot but in another forum I read that it was not always correct to do this as it might over stress the casing. The boat seems to be well balanced when it is at 90 degrees and it certainly makes a difference to its pointing ability. It does clonk a bit though.
 
"Clonking" is probably due to sideways movement in the casing. There may be some wear in the pivot bushes or pin.

I would expect it to work rather like a dinghy, if the board is not fully down, the CLR will be slightly different from the designed position & you may well get some loss of balance (lee helm?). This is less likely to be the case if it is a dagger board rather than a swinger, but you did say swing keel, so partially lifted means that it is swept back from its designed position.

If you have excessive weather helm, then swinging the keel back a bit may make her a bit better balanced.
 
Its a 33 year old boat so I guess it is likely that there is wear on the pin and bushes. I had my first chance to see the keel extended on the haul out and it does move quite a bit from side to side when fully down.

There is some weather helm but nothing excessive. It is a pretty nice boat to helm even when slightly over canvassed and the keel is fully down when going to weather.
 
I think Searush has got it right, sail it like a dinghy, lift the keel a little when not hard on the wind and as you come further off the wind lift it more. When sailing downwind or with the wind on the quarter you can have it half up or more. Use the weather helm as a guide.

I sailed for a few years on a regular basis in a Southerly, I have sailed my son’s First 29 with lifting keel a fair bit, including from Maryport in Cumbria to Fairham, and a few years ago I bought myself a Oceanis 323 with lifting keel.

As for the clonking, when you let the keel down, lift it back up just a little, so that the wire is tensioned instead of slack, this might help. However I am not familiar with your boat. Southerlies don’t have this problem, they have no guide pads or wear pads, in the keel box they just rely on the massive pivot pin and structure around it. The Southerly I sailed on was 20 years old, and had no slack in the keel pivot point.
 
Its a 33 year old boat so I guess it is likely that there is wear on the pin and bushes. I had my first chance to see the keel extended on the haul out and it does move quite a bit from side to side when fully down.

There is some weather helm but nothing excessive. It is a pretty nice boat to helm even when slightly over canvassed and the keel is fully down when going to weather.

I have a swing keel boat - a Gib'sea Master 96 and there was no play on the keel when fully extended. When I took the keel out to repaint it and renew all the shackles, cables etc I noticed the pivot pin was bent out of true and replaced it with a new one I had custom built to the drawings kindly provided free of charge by Dufour. I would seriously suggest that you consider replacing the pivot pin and bearings. - Mine was 20 years old when replaced. Most local engineering shops should be able to do this for you. Just get the right grade of stainless steel for the pivot pin and use Nylon for the bearing - Yes Nylon!! it does expand slightly with immersion but by the time the fitting tolerances are taken up you should have a perfect fit. Net result of the change was that keel operation was much smoother.

Fair winds etc.

Ken
 
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