Selling Two-Step and buying another boat! | Sailing Blog - Technical Hints and Tips - Sailing Television

Selling Two-Step and buying another boat!

Oh boy this is getting to the tough part! For months I have been dreaming of the new boat - what will she look like, feel like etc. But now we are getting around to actually selling Two-Step and its proving tougher than I had thought. Well we did build her ourselves, and for all the years we have sailed her we have always been making improvements to her and looking after her as she has looked after us on numerous ocean miles. She has been a good boat for us and now I have been making up a website to sell her!?!?

Anyway, for anyone interested, I am putting together a page with shots and equipment lists etc. She is a very full featured boat - certainly ready to cross oceans. She may be right for you!

What to buy next?
So now I am zeroing in on the next Two-Step and I keep coming back to wanting a shallow draft cruiser to explore further...

Shallow draft and the Cruising Sailor
Why am I so keen to get a boat that draws less than 4 feet?
Anchorages, canals, rivers, Bahamas!! A big part of the reason we cruise is to explore the places we sail to. And there are many waterways and whole cruising grounds we are excluded from with our 6-foot draft. Although we are almost average compared to sailboats, we are quite deep compared to boats in general. All small craft and almost all power boats less than 70 feet long draw less than 5 feet. Many only draw 3 or 4. So there are many waterways designed for these boats. In more than one occasion we have sat aground in the middle of the US intracoastal waterway. Silting up from the planned 8 or 9 foot depths is only a problem when it affects enough boats I guess. Once we sat directly between the red and green markers of the channel so everyone could see we were squarely in the right place. The Florida Marine Police even came up and complained that we were sitting in the middle of a navigable waterway (not SO navigable I would say). But my point is that as we sat there a large number of craft right up to a 60 foot motor yacht sailed happily around us. We were the deepest boat for those 2 hours. Having a shoal draft would also have let us sail on down through the Florida Keys. The Bahamas is another whole cruising area. Anyone who has visited this cruising paradise will not only tell you how lovely it is but also how it would help to have a shallow draft to see more of it. There are whole island groups out of bounds to our 6 feet. Here 3-feet would be perfect!! Then there are the European canals – much easier to handle with shallow draft. So many places we could visit. Even the canal running up to our home base in Canada just north of Toronto requires less than 5-foot draft.

Isn't it less seaworthy to have shoal draft?
Certainly there have been very seaworthy boats that managed to have a shallow draft by putting the weight of the keel all along the bottom instead of concentrating it in a big bulb. Joshua Slocum's Spray only drew roughly 4 feet. But these boats tend to be slower than modern sailors are willing to accept. They were made within the limits of the materials. Wood just didn't allow the more interesting shapes of modern boats to be made strongly. So if you accept our modern quicker hulls with lower wetted surface area and beamy hulls for more accommodation, you are going to need to put some ballast fairly low to keep them safe. But remember that modern boats are also much lighter than previous craft of the same length. So it is possible to get a good stable boat by concentrating a lot of weight deep in the hull. Obviously you could get away with less weight if you could hang it lower but it can be done.

How do you measure whether the stability is sufficient?
A stability curve can be generated for a particular model of boat. The line basically shows if the boat wants to stay upright (and we all like boats that like to stay upright!!).
The simplest way to look at the stability curve of a sailboat is to see the how much of the curve is above the line and how much is below. The point where the curve crosses the line is also important and is known as the angle of vanishing stability. At risk of oversimplifying, the higher this number, the safer the boat.

What are the main factors affecting stability?
Basically the stability as measured by the curve is determined by the distribution of weight in the boat and the form of the hull and deckhouse. So a boat with a mediocre stability such as a canoe, could be improved by adding some weight in a keel hung 1 meter down, and by building a lightweight deck to stop water coming in when heeled past 30 degrees. Any boat will be improved for (stability purposes) by removing unnecessary weight above the centre of gravity. In fact this is a good reason not to take your collected 30 years of National Geographic Magazines and store them up on the bulkhead. Similarly jugs of water and fuel lashed on deck and the outboard motor up on a bracket, all add to the top heaviness and reduce the stability of a boat.

What about a very deep keel?
The easiest way to improve a sailboats stability and also its sailing characteristics is to concentrate more of the boat's weight lower in the keel. The racing community have embraced this concept! Todays racers have bulbs suspended on a winglike blade and may draw 3 or 4 meters. The newest use hydraulics to swing the keel from side to side to improve the righting moment even more dramatically. For the rest of us cruising in the real world where there are shoals, lobster pots and slips with limited depth these keels are impractical but they are certainly a trend in the racing world and show some interesting potential for cruising boats if the ideas weren't quite so radical.

How about a keel that swings down for offshore work and lifts up for shallow draft?
This isn't a new idea but there have been difficulties in the past. A boat made of wood needs a large area to provide the strength to attach a keel and distribute the tremendous loads of a heavy keel where it would slide or swing into the hull. Similarly fiberglass would need great reinforcement but would be easier to accomplish. And steel or aluminum have easily got the strength to support a well designed movable keel. Now modern racing boats are making canting keels by taking advantage of modern hi strength materials. So although most cruisers will shake their heads at the radical canting bulb keels that swing many tons out to the side of the new crop of maxi-yachts, there is no denying that racers are paving the way for cruisers to follow by showing that keels don't just have to be fixed to the bottom of a sailboat.

What is out there for cruisers?
There are a few cruising boats right now that have shallow draft and have solved the keel problem in interesting ways.

Traditional boat with a centreboard – Classic yachts like the Bermuda 40 have reduced the keel depth somewhat, and added a centreboard to reduce leeway when beating. Simplest to build and proven over years they do reduce the draft but not by much. And since the centreboard usually doesn't contribute much to the ballast, these designs do not offer an increase in stability.

Centreboard in a modern hull shape. French builders Garcia and Alubat (builders of the Ovni series – which incidentally means U.F.O. in french since they do look a bit wild!) have built a number of models in aluminum that have a modern beam and waterline but no built in keel at all. The ballast is concentrated in the bottom of the hull itself, and the centreboard keel that swings down is almost neutral – designed to reduce leeway and allow the boats to go to windward but not add to the righting moment. These boats tend to be heavier than conventional designs since more ballast is required to make up for none of it being lower than their typically 1 meter draft. But these boats are popular with sailors interested in shallow water, and have also done many offshore passages. Jimmy Cornell sailed an Ovni 43 for years and now has another aluminum shallow draft sailboat custom made by Garcia.

Lifting keel daggerboard in a modern hull – European design firm Van De Stadt have done a number of models that have a bulb on a daggerboard where a substantial amount of ballast is hung down to a depth that makes their modern hull shape virtually equivalent to a modern deep keel boat. At sea the boat would perform like a modern racer/cruiser, but by hydraulically raising the keel the draft is reduced by up to 1 meter as you sail into your marina! Disadvantages include the possibility of jamming the daggerboard if you run aground when it is down, and the fact that stability is very affected by the keel. So if you have the keel up you would be careful not to overpower the boat with full sails. In practice you could just remember to reduce sail before raising the keel.

Modern hull with ballast in a centreboard – British-built Southerlies have an interesting system where a deep centreboard comprises 35 percent of the ballast package, and the remaining is in a large plate in the deepest part of the hull. The boats are fibreglass but instead of worrying about how to attach the centreboard securely to the glass hull, Southerlies use the massive ballast plate to fashion a sturdy attachment point in cast iron. That way the loads of the ballast attachment to the glass hull are distributed over the size of the ballast plate. With a heritage of the south of England, the design is meant to be able to dry out by resting on the ballast plate, and she can also deal with running aground since the centreboard is designed to kick up without causing harm. Since the heavy centreboard affects the stability quite a bit, the boat actually has two stability curves. Stability is good even with the board up, but there is greater righting moment with the board down, and of course she will make much less leeway. Southerly seems to me to have the most promising mix of shallow draft, seaworthiness and not too much technology to get in the way. But how do they deal with the rudder when they go aground and how do they lift that heavy centreboard. I am going to investigate further!


- Southerly have sadly gone out of business producing new sailboats. Luckily they built over 800 boats in all the decades they were in business so you can find one on Yachtworld :-)

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