Moody 31 bilge keel Atlantic Circuit

lampshuk

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For what it's worth, the Byron handicaps for the 2 are:
Fin keel 988
Twin keel 1047

That's about a 6% difference.

So considerably less than the difference between old and new sails, weedy or clean bottom and fixed or folding prop.

Not to mention the difference between paying attention to sail trim or being more focused on tea and cake, in proper Moody style.
 

capnsensible

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The difference is slight. And when crossing oceans, even going to windward you probably don't want to steer as close as she'll go; you don't need to weather the next headland, and most boats make their best VMG a bit off the wind. I'm pretty sure that's the case for the Moody 31; I'm not a racer so I've never been that interested, but she certainly slows down when sailed as close as she'll go ( I have tried to weather headlands!). So I think the difference between the two configurations is unlikely to matter even for the West-East crossing.
Iv e been fortunate enough to have sailed both ways, six times each. There is not a lot of downwind sailing, generally, and a lot of grey after the first week or so on the west to east trip....... Have done it in April, May and June. It can be quite difficult sometimes to make much progress east for days at a time. But you get there in the end. ?
 

PaulCymro

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How times change:
"When the ARC first started in 1986 the majority of the boats were between 30-40ft, with many below today’s limit of 32ft LOA. However, in 2016 the average length was around 55ft, with quite a number over 65ft."
I think it's madness these huge boats today. I can never understand what it's all for. Just more to go wrong!
 

Tranona

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I suspect your view might change if you were in a position to own a bigger boat and had the wherewithal to take full advantage of what such boats have to offer.
 

Dutch01527

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Food and water storage should not be a big deal for 2 people on a 31 foot boat. Pasta, rice, dried beans and pulses, canned tuna, couscous, porridge oats, noodles, long life milk, water, dried fruit, honey ect would fit on a single berth with ease.Extra fuel can be stored on deck.

Major issues are weather and crew fatigue. Go for it if thou are happy that the boat is in good enough condition, the weather is right and the crew are are experienced and robust enough.
 

PaulCymro

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I suspect your view might change if you were in a position to own a bigger boat and had the wherewithal to take full advantage of what such boats have to offer.
I dunno man. I really like being able to get in to any port, even the drying ones. There's also something about the challenge of large distances in small boats.
 

Tranona

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I dunno man. I really like being able to get in to any port, even the drying ones. There's also something about the challenge of large distances in small boats.
So did I until I had the opportunity to try something different. Plenty of time in life to experience different challenges!
 

steve350

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I dunno man. I really like being able to get in to any port, even the drying ones. There's also something about the challenge of large distances in small boats.

Of course you may well be in a position to own a larger yacht but simply choose not to. To assume that people sail a more modest size boat due to financial constraints is rather crass. Downsizing to a smaller boat is not uncommon after all.
 

doug748

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Of course you may well be in a position to own a larger yacht but simply choose not to. To assume that people sail a more modest size boat due to financial constraints is rather crass. Downsizing to a smaller boat is not uncommon after all.

Indeed. It also very much depends on your style of sailing.
Going to the West Indies and the Pacific, fully crewed, something bigger might be in order. Day sailing out of Hamble with a crew, then get as big as you can afford and impress the neighbours.
Knockabout sailing in the Channel with a small crew and fair level of marina use, a big boat is a liability. It's expensive and that expense is shared by only one or two. Poor sods are frequently rafted 3 deep whilst something under 34 ft will be snug on it's own pontoon.

.
 

Tranona

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Of course you may well be in a position to own a larger yacht but simply choose not to. To assume that people sail a more modest size boat due to financial constraints is rather crass. Downsizing to a smaller boat is not uncommon after all.
My remark was in the context of ocean sailing, where bigger boats have become more common, and highlighting the need to be able to afford to run a bigger boat. Perhaps too many people buy boats that are too big (particularly for their budget) and find that not only are there many more things to go wrong, but time and cost of fixing limits one's ability to take advantage of what a bigger boat can offer.

Upsizing and downsizing tends to be cyclical, often related to age and not necessarily related to wealth!
 

Island-Runner

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Anyone done a circuit in a BK Moody 31? That's my plan and I'd like to check I'm not being mental.
YES, Two Cardiff yacht members did it it in 2013. you can kind of follow their adventure on the clubs message board.
Two Moody old blokes. | Cardiff Yacht Club Message Board

There was also a TV interview

If its the same boat that was for sale in Devon, then "Elba" is a bilge keeler.
Moody 31, 21.125 € | iNautia.com

I own a MkII Moody 31 and would happily plan an alantic crossing, as my foul weather experiences with her has been nothing but positive. However, if I was going to buy a boat for such a crossing, It probably would't be at the top of my list.
 

Pete7

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We have a M31 with bilge keels. I did speak with Pantaenius UK a while back about insurance for an Atlantic crossing. They said they could write a policy for 6 months European cover and 6 months US. The US part would be much more expensive. Given the insurance market has caught a cold recently with several severe hurricanes in the Caribbean causing a lot of damaged yachts the prices have gone up and some brokers pulled out of the US market. So you might start by looking at insurance.

What would I change on the yacht? more water tanks obviously and probably a windvane like the Sea Feather perhaps?
 

siwhi

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I met a chap with a M31 in the Caribbean about 4-5 years ago who was doing an Atlantic circuit by himself. Was very happy with the boat.

I own a MkII Moody 31 and would happily plan an alantic crossing, as my foul weather experiences with her has been nothing but positive. However, if I was going to buy a boat for such a crossing, It probably would't be at the top of my list.

Similar. We had a fin keel M31 and I would have happily done it in that had we been a couple or solo, but my wife insisted on a larger boat for various sensible reasons (not least so the kids could have their own cabin each).
 

Laminar Flow

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A crew of two requires, based on 30 days with a 50% safety margin, 600kg worth of food and water. To this you can add, for liveaboards, 400kg for personal effects and 160kg for the weight of the crew themselves. So far we now have have a min. load of 1160kg, this does not include any things such as life raft & safety gear, dinghy, cooking and eating utensils, anchors & rodes, chain, spares, nav equipment or anything that is not part of the basic structure & rig of the boat.

The displacements quoted in Sailboat data are at best the empty boat weight or shipping weight. this does not include any equipment whatsoever. by the time you have equipped your boat with even the bare essentials for an ocean crossing she will be 40-50% over weight. This will severely impact her performance, diminish her AVS and ballast ratio and put a significantly higher strain on her rigging, possibly exceeding what it was designed for.

Older style cruising boats are better at load carrying than shallow body modern designs. This is one reason the average contemporary boats are getting larger and why displacement is the true measure of size rather than length. To get a rough idea of what size boat you would need add up all the things, crew, food supplies, water etc in lbs and multiply by 7.5. This will give you a good idea of the size i.e. displacement of a boat fit for your purpose, plus or minus 10%.
Hiscock's 30' Wanderer was some 6" down when they left on a cruise and she had a significantly higher dis/length ratio than a Moody 31.
 

Pete7

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Marine Projects the builder; quote the weight of the bilge keel as 4026 kgs which is 56kgs more than the fin keeled version. On the Gosport Boatyard crane in cruising trim with full tanks, dinghy and engine etc, we weight 5100kgs. Add LF's 1160kgs for people, water and food and his suggestion of 40-50% over the manufacturers build weight sounds reasonable.

600 kgs for food and water for 45 days is 13kgs for two people per day. So 10L of water and 3kgs of food for two. It's also 450 litres of water. Not sure were you would put that on a M31, the tank is 120L.

Note for Paul: even when the tank is full, it has a 2" air gap at the top. Fitting a clear plastic inspection hatch to see inside also allows you to open and brim the tank.

Suddenly the idea of adding a little Katadyn 40e water maker that weighs just 11kgs in place of some of that water looks attractive. It's the one the ocean rowers seem to use for this very reason aboard there 21ft little row boats.

I do question the 400 kgs of personal effects. Perhaps on a large yacht, but at 31ft there isn't room to fit that much. Clothes and a few books etc, so 100 kgs for two people? That brings the stores and people weight down to 800 kgs.

A Moody 31 will sink approximately 1 inch lower for every 400 kgs. We float satisfactory at 5100 kgs and I would suggest on her marks given the location of the sink and shower outlets which are above the waterline at rest. 1 - 2 inches more I don't think would be a problem. Would be worth replicating with lots of drums of water to see the effect before departing.

Pete
 

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Laminar Flow

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Marine Projects the builder; quote the weight of the bilge keel as 4026 kgs which is 56kgs more than the fin keeled version. On the Gosport Boatyard crane in cruising trim with full tanks, dinghy and engine etc, we weight 5100kgs. Add LF's 1160kgs for people, water and food and his suggestion of 40-50% over the manufacturers build weight sounds reasonable.

600 kgs for food and water for 45 days is 13kgs for two people per day. So 10L of water and 3kgs of food for two. It's also 450 litres of water. Not sure were you would put that on a M31, the tank is 120L.

Note for Paul: even when the tank is full, it has a 2" air gap at the top. Fitting a clear plastic inspection hatch to see inside also allows you to open and brim the tank.

Suddenly the idea of adding a little Katadyn 40e water maker that weighs just 11kgs in place of some of that water looks attractive. It's the one the ocean rowers seem to use for this very reason aboard there 21ft little row boats.

I do question the 400 kgs of personal effects. Perhaps on a large yacht, but at 31ft there isn't room to fit that much. Clothes and a few books etc, so 100 kgs for two people? That brings the stores and people weight down to 800 kgs.

A Moody 31 will sink approximately 1 inch lower for every 400 kgs. We float satisfactory at 5100 kgs and I would suggest on her marks given the location of the sink and shower outlets which are above the waterline at rest. 1 - 2 inches more I don't think would be a problem. Would be worth replicating with lots of drums of water to see the effect before departing.

Pete
When commissioning a yacht for an ocean crossing it is a rare thing that she weighs in lighter than expected - the boat must be, after all, fully autonomous and in every sense for the duration. This will include a full set of tools and spares for all the main systems.
In regards to the amount of gear and personal effects: there is a significant difference between coastal holiday cruising and what amounts to some form of full time living aboard in complete autonomy. It should be noted that the OP's plan is for a full circuit, i.e. that, if things work out, he won't be flying home with a bag of hand luggage from Martinique. In this context, the weight estimate designers use for full time liveaboard, as in a floating home, is 450kg/per person for personal effects.

Great care must be taken not to confuse waterline plane loading (pounds per inch immersion) with actual load carrying capacity. The real factors that determine load carrying ability are displacement, freeboard and robustness of construction, including and especially the rig.
 

Bajansailor

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Here is a current post on the Boat Design Forum by a lad who wants to cross the Atlantic in 7 days, under sail, in a 30' catamaran.
And he reckons that he only needs 2 litres of water and 500 grammes of food per person per day....... :D
trans-Atlantic motorsailer

I think he would be better off in a Moody 31 - certainly much safer, albeit a bit slower.
 
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