Hi,

I have just posted a design in JRA members files/drawings/David Webbs boat designs/ Korora 1 and 2 a design that I have been working on for the last few months. It seems to meet many of Annie's requirements. The design is a work in progress at the moment but I will be without a drawing board for the next few months so I have posted the design for comment and feedback.

   The hull shape is pretty much finalized but the interior layout is still open to change as also is the rig. I have shown two options for power, inboard diesel or outboard in a well. The draft is two feet and the box keel will allow the boat to be beached and the bottom cleaned except for the base of the box keel. The center plate is a drop plate similar to those used on the New Zealand Scows and the small forward centerboard is for balance and to make the boat steadier at anchor. The small mizzen sail has a fixed boom on a rotating mast and can be used a balance for the mainsail, to help steady the boat at anchor and to power as self steering gear similar to that on Gypsy Moth 4.

    Any comments would be appreciated. Thanks, David.

Gary Pick wrote:

How about this one Annie?

Harry Sailing Scow

Arne Kverneland wrote:

I’ve been thinking along similar lines as David does above, and I find it very hard to design a boat that fits within Annie’s specs. Shallow draught and offshore weatherlyness is not that easy to combine.

One spec. that I have added myself is that the boat must be easy to build and to fit the interior into. I therefore focus on a single chine (plywood) boat with flat bottom.

Within the 24”/61cm draught limit, I think it is possible to fit a stub ballast keel, either one central one or twin stubs to stand upright on. It could be smarter to use one stub as this would give better access to one bottom side (at the time) for scrubbing.

One specification I would most certainly break is the 26’/8m LOA limit. I would rather focus on the displacement of 3000kg. With some overhangs the LOA would be better at 8.5  -  9m. Spreading the 3 tons over a bit longer waterline (around 7m) can be done with straighter and less complicated hull lines. A 9m boat at 3 tons will be faster than an 8m boat with the same sail area or engine power, and it will be easier to build.

Then there is the request for a quiet-at-anchor bow, quite important on a floating home. This could well be the showstopper for the sampan type I have in mind. Therefore, I’d better shut up. I should rather build a big (5.5  -  6m / 250  -  300kg) scow/sampan type daysailer for myself first, before suggesting the type to others.

Arne.

PS: Annie, just for the record, is the 3000kg displacement the dry or loaded weight?

Easy to build: I'm all for that.

David Tyler wrote:

While I would love to draw for Annie a sweet little flat-bottomed traditional Chinese junk, I feel that it would be very difficult to clean the bottom when on the beach. In that respect, I've got on well with Tystie's hull form - a sort of curved 'V' below the chines, with a strong central keel that takes the pounding as she settles down in less than ideal conditions, after which she gently and obligingly rolls onto one side or the other so that I can scrub. When I was in northern waters, I relied on the Copperbot, but found it to be inadequate for tropical waters. Of course, my pivoted bilgeboards won't act as legs, but the daggerboard-style bilgeboards fitted to Malliemac can do just that, and they take up less room in the accommodation. Unlike a centreboard, they don't clog with mud. 

Tystie has internal ballast, and a hull depth of about 2ft 9in, so a draught of 2ft should be achievable on a length of 26ft. However, I don't know whether sufficient stability can be obtained with internal ballast at this hull size, so it might be a good plan to incorporate some external ballast in the form of, say, a length of old railway track on the bottom of the keel, for its weight and strength.

I really like the idea of daggerboard-style bilgeboards.  Can they be made to be controlled from the cockpit, I wonder?

How about this one Annie?

Harry Sailing Scow