Double enders

[hotsuncoolwind]

I ma contemplating building a prototype 8 metre lapstrake double ender similar to eun mara, but with a displacement of about 2500kg and a beam of 2.5m

Anyone have sailing experience with double enders, I have been told they are no more seaworthy than boats with a wide transom, and that they pitch fore and aft in a chop at anchor because there is no flat section to stabilise them. I DO love the look of these boats. but practical anecdotes would be welcome.

Paul

[Hwyl]

I think the trick is to veiw the pointed stern as an extension and not part of the boat, a kind of skinned over boomkin. You see too many double enders with weight in the ends. The ends in any boat have to be light, but more so for the stern of a double ender.

I sailed 210's in some bouncy stuff and they behave well. hey really are 18' boats with 6' pointy things at either end.

Here's a link to the class assoc http://www.210class.com/ the photo's blow up your thread.


Are you going to keep your Navigator (I think it was)

[ 04-30-2005, 07:41 AM: Message edited by: Hwyl ]

[Billy Bones]

Originally posted by Hwyl:
I think the trick is to veiw the pointed stern as an extension and not part of the boat, a kind of skinned over boomkin. Bang on the dot. It isn't a perfect analogy but it's a pretty good one. This is why I've always had trouble with the rigs on Iain-O's Caledonia and similar designs. They are, in effect, boomkins with boomkins.

[Stephen Hutchins]

I can get a longer waterline for the same overall length plus a flater, longer run by drawing a double ender. At least on that behaves well in the sea.

[Frank E. Price]

Paul, you surely don't take seriously a generalization as broad as, "they are no more seaworthy than boats with a wide transom, and that they pitch fore and aft in a chop at anchor because there is no flat section to stabilise them."

The pinky fishing schooners had the reputation at least, of being about the most seaworthy boats of their size anywhere. The two worst-behaving boats in a following sea I've been aboard both had transom or short counter sterns. Some boats roll and bob and pitch around at anchor in apparently flat water, but I haven't noticed that whether the thing has a sharp or square stern has anything to do with it. The most stable boat for its size I've been aboard, at the dock, had a very deep V-bottom and cement ballast. There no doubt are boats that fit the generalization, but in general I thinks it's hooey. Keep reading; better yet, go sailing on lots of boats.

Frank

[Ian McColgin]

We've had a couple of earlier threads on double enders that you can raise by search perhaps.

There are about as many theories about sterns as there are about bows and a lot of total nonsense.

Atkins and some of his followers go for great symetry in the lines - Atkinized to eliminate any raking waterline and so on. But in general you'll notice that most designers of displacement sailing boats now give at least some hollow to the bow waterlines and some convex curve aft. A boat too skinney at her rear will, like a sailing whitehaul, squat way too early in her own bow-stern wave trough.

Most boats with transoms, and certainly almost all of LFH's, could be drawn out to a pointy stern. But not all pointy sterns have anything to do with being a double ended. Study Bob Perry's canoe stern lines a bit. Contrast with Creelock. These are sterns that do interesting things and which definatly could not be cut off at all.

Sometimes a bit of transom is far better than drawing the lines up and back to a natural pointy end well above the water. Depending on the hull shape and wave formation, the hull may drag more water and slow more than could be gained by the increased waterline. In cases like that, the angle between hull and transom gives the water a nice seperation point.

A good and paradoxical example would be the classic Cape Cod Cat Boat with it's barn door transom. Attempts to round those hindquarters out result in a truely unmanagable tub under sail, though not a bad motor hull for tow and launch work. Throws a huge wake no matter what.

There are those who've waxed poetic about the ability of a pointy stern to part the overtaking sea. I've been on boats of all types that would broach if you just thought about it. Been on slab sterned schooners that could run the face of a big wave every bit was well as the superp Marco Polo type such as my own Granuaile.

I applaud your idea for a pointy stern boat and agree that in that sort, whether clear of the water or long lined plumb stemed for length, it must be kept light, free of accomodation or even storage access. But the real heart of your success or failure will be on the shifting waterlines as the boat heals.

G'luck

[hotsuncoolwind]

Thanks for your valuable comments. I will post the lines for your appreciation. I really like this boat, kind of like Madrigal but without the reverse transom.

Paul