Celebrating Belle Starr On the Water

At the end of a very productive week, we find the sloop-rigged cutter Belle Starr in the water for the first time in many years.

Belle Starr, as you know, is a Stone Horse, built in wood, as originally designed by Sam Crocker. This classic was designed in 1931. Less than forty were built before production was interrupted by WWII. Some of the original wood models are still sailing.
An additional 150 fiberglass Stone Horse models were built by Edey and Duff between 1969 and the early 1990s.

The defining feature of the Stone Horse 23 is her raised, flush foredeck and integral coamings. Twenty three feet on deck, the overall length of the Stone Horse is 28’-3” with a bowsprit and boomkin. The hull has a full keel with hard-chined sections and a transom-hung rudder.

After a year and a half in the shop, Belle Starr touched water this week at family-owned Zittles Marina, outside Olympia, Washington. The launch was flawless, stepping the mast went smoothly and the boat sat pretty on her lines. Its fair to say, this deserves a celebration.

With an enormous amount of help from friends and the professionals at Zittles, this project has reached a milestone. My very good friends, Doug Follet of Olympia, his brother Steve, from Vermont, and Dougs son, Ian, of Seattle, all chipped in to make two days of rigging and outfitting go smoothly. My heart-felt thanks to these generous men!



Launch Day for Belle Starr from doryman on Vimeo.

The four of us took the cutter out for a trial sail and wouldnt you know, a calm day of 3-4 knot breezes suddenly built to 15 knots. We turned around and headed back but there was enough time to see what could be done to finish the rigging.




test sail from doryman on Vimeo.

Belle Starr behaved like a thoroughbred. Look for updates, right here, in the days and weeks to come. She is bound for adventure...

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Stability with Water Ballast

A potential builder of the Didi 950 asked me a question about stability with water ballast. He could not find an explanation on the Internet describing the effects of water ballast on a boat when capsized, so here it is.

After looking at the stability curve, he was concerned that the stability curve with water ballast to windward, the normal position for sailing in strong winds, has a very large area of negative stability. He wanted to know how that affects the time that the boat will take to right itself if capsized. This is a natural question following the amount of discussion that has been happening after our recent capsize in the Didi 38 "Black Cat" and the very rapid manner in which she returned to upright.

Shown below is the stability graph of the Didi 950 in fully loaded condition; click on the diagram to enlarge it. This is the condition of lowest stability due to the inclusion of crew, stores, liquids and many other weights that are above the centre of gravity (CG) of the boat. There are three curves shown. When looking at the graph, consider that the area enclosed by each curve above the horizontal 0 line is a measure of the energy that is required to take the boat from upright to the point of vanishing stability (AVS) where the curve crosses the 0 line. Until the AVS is reached, the boat will return to upright if no additional heeling force is applied to it.  Beyond the AVS the boat will continue to full capsize unless there is another force being applied that will return it to the positive side of the AVS.

The green curve is with ballast tanks empty, so akin to sailing a boat that has no water ballast. This curve is very similar in form to that of "Black Cat", with the area enclosed by the curve above the 0 line many times greater than the area enclosed by the curve below the 0 line. She would right herself very quickly with no water ballast. The red curve is with the windward ballast tanks filled, good for powering to windward or power-reaching in strong conditions. The blue curve is with the leeward ballast tanks filled. One would not sail her like this but it is a situation that could result from an accidental gybe in strong winds.

Didi 950 Stability Graph. Click to enlarge.

With no wind or waves and the ballast tanks on one side filled, the boat will not rest upright. It will heel over until it stabilises at a heel angle that places the CG vertically in line with the centre of buoyancy (CB). That will be the nearest crossing of the curve with the 0 line, which is at 5 degrees in this case, seen on the blue curve. Add some wind to bring the boat to 0 degrees heel and the righting moment that is working is the point where the red curve hits the left edge of the graph. Without water ballast the boat must heel to 6 degrees to reach the same righting moment. That is where the power benefit is coming from with water ballast, the boat will sail more upright than with empty tanks, in the same wind strength.

Note that all three curves are closely bunched when the boat is heeled 90 degrees. This is a knock-down situation, probably from losing control when driving hard downwind under spinnaker. The mast is horizontal but not in the water. This bunching of the curves at 90 degrees is because of the position of the ballast tanks in this design, low in the boat fairly close to the vertical CG. There would be a bigger spread if the tanks were located high up under the deck.

The red curve shows the benefit of increased righting moment when the windward tank is filled. There is considerably greater gain in stability shown by the red curve than lost stability, shown by the blue curve, when ballast is on the wrong side.

All three curves show that the wind alone cant capsize the boat. When the mast hits the water there is still considerable righting moment available for all three situations. If the boat is in large waves and hit by a big one while knocked flat, the added energy from the wave can capsize the boat in all three situations. 

It seems counter-intuitive but the condition most likely to invert the boat under wave action after a knock-down is with the water ballast to windward (red), i.e. the condition in which the boat will be sailed in strong winds. This is because after the water ballast passes beyond the point where it is vertically above the overall CG of the boat that extra weight is on the wrong side of the CG and is helping to capsize the boat rather than to bring it back to upright. It pulls the red curve below the green curve and reduces the AVS from 133 degrees to 122 degrees. 

Overall it takes more energy to capsize the boat from upright with water ballast than without, evaluated by comparing the area enclosed by the red curve with the area enclosed by the green curve. When the area enclosed by the blue curve is compared with the green curve, there is very little difference. It will take a similar amount of energy to capsize the boat without water ballast and with water ballast on the wrong side, when going from upright. Ironically, the wrong side has the greatest amount of reserve stability after a knock-down and has the greatest angle of AVS, so it is the condition least likely to capsize after a knock-down.

Back to our capsizing boat. Once past 122 degrees it is into a big range of negative stability that shows as the area enclosed by the red curve below the 0 line, taking it all the way to 180 degrees, i.e. totally upside-down. But see that the curve does not return to 0 at 180 degrees, which means that it is unstable at that angle. Same as happens when the boat is upright, the water ballast off to one side prevents the boat from resting at the 180 degree position. It has to rotate to where the CG is vertically aligned with the inverted CB. That is at the point where the curve crosses the 0 line. If the red curve is extended to the zero line it will be to the same angle that the blue curve crosses,  i.e. 160 degrees.
 

There is no windward or leeward when the boat is upside-down, the sails are under water. The boat is stable in the 160 degree position, so leaning 20 degrees to one side of upside-down. It needs to get past the nearest zero crossing to come back to upright. The boat doesnt care which way it goes. It needs a lot of energy to go back the way that it came along the red curve but very little energy to get to the 140 degree AVS crossing of the blue curve. With the motion from just a small wave it will continue past that 140 degree point. Once that point is passed, the righting moment of the blue curve takes control and will return her to upright. If the rig is still standing then the sails will fill and she will be back into the stability situation shown by the red curve. She has capsized along the red curve and righted herself along the blue curve.

In essence, it will take a lot less energy for the boat to right itself with water ballast than without, so she should right herself more quickly with the water ballast. The difference is that without water ballast she can go either way from inverted to upright but with water ballast she has to go full circle.

To visit our website, go to http://dixdesign.com/

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Shallow water skiff shapes ideas

Here are some of my old musings of developing skiff shapes to bring to reality. As I described earlier in my blog of how I like to make a half hull of my vision - idea . I do this after I have done all my weight calculations in advance. Shown are a few past ideas in their growth stages. Sorry but I would love to be able to do this all properly but all I have is the iPad that I got for Christmas this year from my daughters. With out this contraption I probably would not take the time to do all this. Right now it is flat calm with lots of light rain about so Im inside with a fan on doing something. The iPad is great as I can do this stuff with a simple inverter on our sailboat as we move about and post it later. No TV time in my life so have extra time to fiddle here.

So look at the wood half hull against the mirror. The sections are glued to a 1/4" piece of wood,without this it would sit flush against the mirror with the thickness of the mirror being the center line. This is how it was done before 3 D programs . It does make you feel like a peeping Tom though as you stretch around trying to see the whole thing. Each section is drawn out from the center line to scale. Here you can calculate how many cubic inches are in each section. I do not have the side views showing which would tell and show you the distance between each section. It would not show up here very well.

What I will do this summer is draw up 3-4 new skiff shapes from past knowledge with all dimensions easy to draw up to full size hull sections. These you will be able to cut out and install on a simple building jig and from there you will be able to plank up in light cedar strips, Baltec balsa core strips or Core Cell brand planking strips. From this you fair and then glass the outside. When fair, flip over,

remove the forms and glass the insides. Then you finish the inside. To build a deck I will explain all the ways it can be done simply later. I will put this here for free. In the mean time anyone planning on building a skiff needs to read up a bit on strip plank boat building. This is the same as building a canoe; just a little more odd shape and it has a transom. I will get a list of books or pamphlets to look up.

In looking at these shapes it is easy to start to see how many ways and directions you could now reshape and go. Ha, it can be daunting if you do not have a weight list and a clue as to what the finished hull will weigh. Here I come back to having the vision, idea, whatever. Details. 

Of course if you are going to start a new company and you want to follow in the foot steps of something that is already well proven and established then all you really have to do is make a facsimile of it as all the thinking has already been done for you. If you do make it better, and at a better price good for you. 

Now with all the shapes here you still have to decide on which side of the half section line you will put your hull thickness. Makes a difference . Take your numbers from the center line out wards and up to the LWL. This is the quickest way. This method shown here has been used for centuries with the creations of some of the most beautiful boats in the world. Go to see the Herreshoff museum in New port RI. He did all his boats this way. There is not a Yankee boat builder up north that does not know this system nor a Carolina one either. The computer today is the way to go though if you have one.

  Another idea; this shows how you can take an existing boat today and measure or take its lines sections. Without knowing its length between perpendiculars you could stretch this boat out to ......

In this shape here I wanted a good sea boat at rest that would not be as they say here too "cranky" .

It has good freeboard and was a good all round skiff. I lowered the spray rail on this a bit in the bow area when built. Today I would change the stern section aft so this is obsolete in my mind.

 You can see the half sections above and the half hull below. 

Cheap 3 - D rendering 

You can see here how Im drawing in a bit of crown. I like crown a lot. It adds tremendous strength over a flat surface. Also you can gain some Disp. But then you have to be careful where its going to direct the water flow. I do not want crown in my skiff decks as it is a pain in the butt to fit the hatches so the will not squeak and lay flush. 

On this sheet you can see the displacement calculation that I wrote down from a simple lines program that I found on the Internet at the time. I put in all my half section numbers and in a second it spit out all these numbers. I had already done it my old way and every thing was pretty close. In the upper left corner you can see the displacement numbers for three different water lines. This you have to think about a lot as the guys, people that will be in the boat, are most likely going to weigh over 200 lbs.

The rest of the numbers there are just adding up Disp. If I posted all my calculation sheets it would be so boring. But I keep em for reference. This is a heavy skiff at close to 2,000 lbs with all the sports in it.

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Todays motor home on the water

I like to sail on boats that I can see and feel the wind. By seeing the wind I can see the ripples on the water, by feeling the winds I can tell when running down wind at night how far the wind has veered by the feel of it against my ears and neck. I also sail to see and enjoy the pure energy of how a vessel moves along by the force of the wind. When entering a Harbour under sail all my senses are on alert to avoid shoals ,other boats and to see a possible wind shift.

So my sailboats are very clean of gear on deck and around the cockpit. At sea I can rig in a second a nice sun awning from the boom gallows to the aft railing supports that were made for this. When its blowing hard I take this awning down and now have a clear view. When going to weather in rough going the wind vane steers the boat and I can just sit in the doghouse and watch the world go by. 

Coming into port in nasty weather I done foul weather gear and just deal with it. At anchor we have a very nice awning setup.

Todays group of sailors think in a different way. These people were raised on tv , computers , video games and commuting by car long distances while talking on the phone and listening to talk show hosts that are bitching about something. These people are used to being in enclosed areas on the way to work, at work and when they get back home. One day they decide to become a sailor - cruiser and start on the computer looking up what they need to live on a boat that will make them feel at home.

This trend has brought us the Island Packet crowd, the huge Room-Ma-Ran catamaran crowd and all the other group of sailors that want to stay under cover till the last instant when one of them has to go forward and lower the anchor. Otherwise they want to stay in what is the equivalent of a sailing motor home. In the typical cockpit of one of these vessels you will have a steering wheel that is over shadowed by a huge GPS system flanked by the VHF and loud hailer . To see around this getup one must stand up on tip toes to see over. Now the compass is in there somewhere but this crowd has the GPS full map system so who needs to look at that , all i need is my waypoint book .

Sailing under a fully enclosed Florida Room like you see on the intra costal where they enclose half the property and pool area under a huge screen cage . Side flaps down , the little window to maybe look up at the set of the mainsail but who does that and the sun might find me so its closed.

What the whole sailing experience comes down to is seeing the goose neck of the main boon and maybe the genoa tack at the bow.

Sensory deprivation at its best. But hey the sun cant find you under  all this crap.

At night with the GPS TV show going on all night vision is gone . But the good this is theyre in the safety compound of the FLORIDA ROOM.

Id rather experience the sea that I sail on. 

Todays floating CARAVAN-MOTORHOME at rest . They have missed the channel completely . The wind is in the east coming from their stern . They have set the anchor to leeward in the channel they should have been in. Three more of their tribe are consoling and trying to figure out what to do. 

In passing by in our dinghy going home I suggested to put a kedge out to windward and put a strain on it so when the tide floats them they will be heading into the wind and not drifting into the channel and onto the leeward rocks. They got off fine.

But iam sure they missed the channel because they were not looking at it but at their GPS TV show

Enclosed in the saftey of the FLORIDA  ROOM.

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Water tanks installation

I have eight water tanks for my potable water supply located under the forward sole of my boat. The first tank I built I measured for cubic footage, then filled it with water, and by using a shut off valve and a five gallon bucket I was able to measure the amount of water in the tank. My method of measuring cubic footage and measuring with the five gallon bucket gave me about the same volume of water within two gallons, so Ill stick with measuring for cubic footage vs filling each tank to get volume. I have 325 + gallons worth of water tanks.

After the boat is insulated and Im assembling components of supply, vent, and filling of the tanks, Ill post more regarding the system as a whole.

Im mounting the water tanks using a flange welded to the tank ends and a corresponding bracket welded to the hull of the boat. Where the bracket is deeper in the hull ( by the center line of the boat), I used studs welded to the hull bracket that the tank flange will drop over. On the less deep end of the tank ( outboard ends), I used nuts welded to the hull brackets that the tank flange will bolt to. I used 30 mill pvc pond liner I had laying around the shop to act as a gasket to go between each tank flange and hull bracket.

I had installed the tanks prior to final painting to make sure all the brackets would work and also that the tanks would finish out below the sole framing. I also needed to verify that the valves I was using on the supply end of the tanks would clear all the steel framing. I ended up having to adjust the access holes in the frames for the tank fill lines ( I guess I screwed up on the cut twice measure once thing). 4 3/8" clearance between the front of the tank and the center longitudinal frame of the boat is barely enough ( it fit) room to get a close nipple, valve, close nipple then a "T" for the tank supply. I dont think the Governator would be able to get his arm down in that space to operate this gate valve, but Im able to so Im happy with the final fit. Because I had installed the tanks prior to painting the tank install went fairly smooth. My 13 year old son helped me as the tanks are to large for one person to handle. The only real issue we had was that the amount of paint on the hull brackets caused me to use a tap or a die to clean up the threads on the respective hull bracket. The tanks are a tight fit between the frames so we used as much care as possible lowering each tank into its "bay" so we would not damage the paint. It would take a hard hit to get through all the coats of paint in the bilge area, but I still was very carefull.

I held off installing the tanks as long as possible to try to keep the trash generated from bolting the firing lumber to the frames from getting under the tanks.

Conall

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