More on Stability with Water Ballast

John Gilbert asked a question in response to my recent post, Stability with Water Ballast.

I do not get why the red and blue curves do not meet up at 180 degrees. Inverted the boat has no windward side as you point out, so you have water ballast on one side and none on the other side. As you have drawn the curves you have powerful stability in the  inverted position with the water on one side (red), but actually a righting moment if you have water on the other side(blue). What is the difference?

To help with understanding this I thought it better to write a new post that expands on the dynamics of stability than to try to answer it in the comments section after that post.

This will be more easily understood by seeing a diagram showing the stability graph expanded through a full 360 degrees rather than all conditions overlaid on top of each other in a 0-180 degree range. This is exactly the same stability info for the Didi 950 as shown in the graph of my earlier post but shown in a different manner.

Diagram of Stability through 360 Degrees

I will start with the green curve. This shows the stability without water ballast. The centre of gravity (CG) is on centreline. The stability curve intersects with the horizontal grid line at 0 degrees heel and increases identically both to left and right of the 0 degree line, so the boat will float without any heel to either side when right way up. The boat will stay that way in the absence of any wind, wave action or crew movement on the boat.

Follow the green curve until it comes down past 130 degrees to again intersect with the horizontal line at the Angle of Vanishing Stability (AVS). Then it enters a range of negative stability where it will proceed toward upside-down. At 170 degrees it crosses to above the horizontal line again. This indicates that the superstructure volume is trying to turn it back upright and doesnt want the boat to lie totally inverted. It will easily flop back and forth between the 170 and 190 degree points. The boat can return to upright along either green curve.

This all depends on a totally waterproof superstructure, of course. In practice water is likely to enter the boat at a rate that depends on what is open at the time, which will affect the inverted stability. 

Moving on to the stability with water ballast, in my earlier post I said that the boat will capsize along the red curve and recover along the blue curve. I explained the relationship between the two curves but that relationship is not easy to visualise if only seen across the 180 degree range.

In the diagram above you can see that the red and blue curves only meet in two places and both are on the horizontal line. These are the two points at which the boat will rest when there are no outside influences from wind, waves or crew movement.

The boat cannot rest totally upright nor totally upside-down because the weight of the water to one side is heeling it toward that side. It will rest at approximately -5 degrees heel instead of upright and at 200 degrees instead of upside-down when inverted.

Bearing in mind that the areas of the curves below the horizontal line indicate how much energy it needs for the boat to get past the AVS points so that it can right itself when in that 200 degree situation, it is now easy to see that it will take a large amount of wave energy to get past the AVS of the red curve but a very small amount of wave action to get past the AVS of the blue curve.

This graphic shows that if a water ballasted boat capsizes it will do so along the red curve but it is very unlikely to return along that same path, nor is it likely to stay capsized for long. Once past the AVS of the red curve the negative stability will push it to 20 degrees past upside-down. After that the blue curve will take over and almost guarantee that the boat returns to right-way-up pronto.

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Water Tanks

My current boat ( 28 Carver Mariner) has a whopping 25 gallon water tank and Im amazed at how long we can make that 25 gallons last. On the current boat we use water primarily for washing dishes and an occasional quick shower. The head on the Carver is raw water flushed so we dont tap into that precious 25 gallon supply.

The water tanks on the trawler ( I guess Im going to have to name her soon so I stop calling her the " trawler ") are constructed out of stainless steel. I went with stainless steel vs plastic for a few reasons. Stainless is considered top of the line in regard to potable water tanks. Due to where Im placing the tanks it made more sense for me to fabricate the tanks vs having them fabricated out of plastic. I used 14 gauge 316L for fabricating the tanks. All the associated fittings for the tanks are 3/4 NPT stainless ( fill, vent, supply) couplers welded in place. All the tanks have one center baffle running across the width of the tank. The tanks fit between the frames of the forward area so the tanks have to fit into a 30" wide space. Because of the 2" flange I welded on to the frames I had to make the tanks 27" in width to give me a little room for the install. I might be kicking myself in the ass years down the road, but I decided to not install inspection covers in the tanks. I have a total of 8 tanks giving me approximately 350 gallons of water.

The tanks are held in place with a flange welded on to the front and back of each tank. The forward mounting system consists of a bracket welded to the hull with 3/8 studs welded to that bracket. The forward tank flange fits over those 4 studs and is bolted down. The rear mounting system consists of a similar bracket only I welded nuts to that bracket and used four 3/8 bolts through the tank flange to mount the rear part of each tank. I used studs on the forward mounting system because the bracket is so deep it was easier to get a nut started vs getting a bolt started. It was also easier installing the tank by dropping the tank over the studs then having a little wiggle room to get the bolts started in rear of the tank. For 3/8 studs and bolts I drilled the corresponding mounting flange to 1/2 " and used thick washers for the mount. I made a gasket out of flexible PVC to help isolate the tank bottom from the mounting brackets ( no metal to metal contact other than the mounting hardware). I allowed myself 4" of clearance between the front of the tank and the center longitudinal frame ( center spine). 4" of clearance was barely enough room, as it is a tight fit to get my arm in there. All the tank mounting hardware is stainless steel

To supply water to the pump I welded a 3/4 stainless coupler in the the bottom of each tank. Having given this a little more thought I now wish I had used a pick up tube entering the top of the tank and going to the bottom. Too late for the pick up tube method now, but again I wish I had gone that route. So each tank has a coupler welded in for supply, followed by a gate valve for each tank,followed by a "T" for each tank, all of this terminates into a common supply line leading to the pump. I went with this set up so I could isolate each tank vs all eight tanks having a shared liquid level. If I ever have a catastrophic failure of a tank, I can take that tank off line and not loose all my water. I also have the choice of just filling a couple of tanks if I want. Since I am able to isolate the supply side of the tanks, I also have to be able to isolate the vent side of the tanks. All the vents will terminate at a manifold that can be valved before venting at the wheel house deck above the fill point. The tanks will fill from two points on the wheel house deck via port or starboard fill pipes. Because of the large cabin and wheel house roof areas Im making provisions to be able catch water off the roof to fill the tanks.

I air tested each tank to 6 psi as this will be more than the static head the tanks will see once the vent tube fills to the deck level. After I fabricated the tanks I installed them to check fit and make sure all my brackets would work so I could start the interior painting. If I had been a little more careful with my measuring and fabricating I could have squeezed another 50 gallons of storage in my system, but all in all Im happy with 350 gallons.

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No water for a bit

When the tide goes out from under your boat you want a nice soft spot for your boat to sit on for the next 10 hours or so. Sand is great, mud is nice but muddy. Round rocks ok , but move the conchs out of the way if you can. Not for the boat but for them as 16 tons is a lot to bear for the duration of the tide.

This is our latest project boat. Its an Irwin 31 built in1968 of solid fiberglass. Nice lines , shallow draft, good sails, 800 hrs on the engine, and bought for less than the price of a used 6 hp outboard. Here she is saving us $ 400.00 on a one day haul out to put in a new stuffing box. Sheer legs made from beach wood and line straps to aft chain plate. She draws 36" . As she sits she is solid as a rock.

This boat will be our Bahamas boat to keep at our place so we will always have a boat to use when here even if we are off somewhere on Hogfish M.

A day at the beach in Abaco at Bill and Leslies on Manjack Cay.

In shallow water so we dont have to use the dinghy. This is Saddle Back Cay in the Exumas. We were caretakers there for 3 years 20 years ago. Have gone up and down on this spot twice a day ....a lot .

Kinda shallow

 

Looks like a big Heron from this angle sitting on brown sand.

Sitting on the beach in cold water to scrub the prop and bottom. 

Nothing like a nice sand beach to let the boat have a rest on. Kinda like looking at a big ole square Elephant Seal here resting from all that time at sea.

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Fresh water system

The fresh water system is complete and ready to use. Once I finish the shower tile and connect the drains to the two sinks I have installed, I think Ill add a few gallons of water to tank #1 and test the system.

I have eight stainless water tanks under the forward sole of the boat. The tanks primarily reside in the master cabin and kids dressing room between station #9 and #5. Total capacity of the tanks are about 370 gallons. There are no tanks under the bathroom or kids cabin.

My plan for having 8 water tanks was for obvious reasons to fit them under the sole between frames and get as much fresh water on board as I could. To prevent one tank failure from taking the water system off line, I provided a shut off valve for each tank. The tanks are connected in series, so this required a valve at the tank along with "T" connections. Because I wanted to have the ability to take any one tank off line, I manifolded the vent lines and fill lines together on both the port and starboard side. I have a one fill and vent manifold on both the port and starboard side of the boat. I can close any one vent or fill line via a valve at the respective manifold to totally isolate any one tank. The vent lines are 3/4" from the tank and connect together via a 1" manifold that leads above deck. The fill lines are 1 1/2" that lead to an 1 1/2" manifold that reduce down to 1 1/4" leading towards each tank. I used flexible sch. 40 PVC for the most of the fill lines and 3/4" rubber push lock hose for the vents. All the manifolds and fittings are rigid, sch. 40 PVC with pressure fittings. The picture showing the fill manifold also shows my engine room bilge pump and forward cabin bilge pump discharge lines. The bilge pump are 1 1/2" discharge. The overboard discharge for galley sink is just forward of the bilge pump discharges. In this picture, the galley sink discharge is not connected yet, but you can see the fitting, painted white, welded in to the hull. This is a busy area of the boat with a lot of piping between station #9 @ # 8.

The series connections for the tanks happen in the bilge area at the center longitudinal frame of the boat. The common line manifolds together forward of station #9, which is the water tight bulkhead separating the engine room from the master cabin. The now manifolded lines pass through the water tight bulkhead via a water tight seal and the now one line enters the engine room where the pressure pump resides. In order to keep an eye on the water level in the tanks, I made a simple sight gauge out of clear SCH. 40 PVC. By closing the valve leading to the pump and opening the valve leading to the sight gauge, I can see the liquid level in the tanks. I have a threaded cap on top of the site gauge Ill have to loosen to let air out of the gauge to get an accurate reading. The gauge is easily accessible by removing a sole panel. The gauge is threaded into a "ELL" fitting and is easily removed for cleaning or replacing.

The pressurized supply line travels under the engine room sole where it passes through another water tight bulkhead via another water tight seal and ends up in the lazarette where the water is distributed to the rest of the boat via a PEX distribution manifold.

I used a home style water heater that hangs from a bracket on the wall. The water heater uses a 1500 watt element, so it will pull 12.5 amps @ 120 volt. Im going to leave this device off of the inverter circuit, and commit to using the generator when I need to make hot water. The tank is 8 gallons, so we will be able to store enough hot water for hand washing and dish washing. When we want hot showers, well have to fire up the generator. I do not trust the wall hanging bracket to hold the water heater fast in many boating situations, so Im going to strap it to the wall with some sort of straps.

I located the pressure pump in the engine room under the work bench and below the steering hydraulic reservoir. This location is still easy to get to regarding maintenance, but it was not my first choice. I can easily sit on the engine room floor and do any service work or repair to the pump without having to get in any contorted position. All through the build, Ive been trying to build with maintenance and repair in mind, and I dont want to design or build any system that requires a contortionist to work on things. I decided to use a moderate priced pump system that was sold as a unit. The unit is four GPM with the cut off switch set for 45 psi and the cut in set at 30 psi. There is an inline strainer before the pump and a small accumulator tank after the pump. I would have liked to have a little larger accumulator tank, but well just have to see how this unit performs. The accumulator tank is a tank with a bladder in it that stores water pressure so the pump does not have to run every time the cold water is turned on.

I used 3/4" potable water grade suction hose with stainless wire in it for the suction side of the pump, and 1/2" PEX for all the pressure side. The suction hose is fitted with barb fittings and hose clamps. Id prefer to have compression fittings, but hose clamps seem to work better in the bilge space and they are less expensive. Because of the mounting issue of the hot water heater, I added bronze unions to make the water heater removal a quick and easy job. I also added quick release fittings at the pressure pump to make pump removal easy.

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Water tight doors

While waiting for parts for the steering system I decided to install the water tight doors in the engine room. As my son would say, " everything tight doors" is really a better description.

The doors have been laying around the shop ever since I bought them at the start of the build. I welded the frames in to the bulkheads, then forgot about the doors. The door leading into the engine room from our cabin is a six dog quick acting door with a port light. Since I dont need the aluminum dead light that came with the door, I took it off. The port light glass in this door is 1/2" thick tempered, and the door itself is 1/4" thick. This door is what I would call severe duty, and is both water tight and fire tight. When this door shuts, things are pretty much final, and no air or water is getting past it.

The door leading from the engine room to the lazarette is a four dog door that is not quick acting. It too, has a port light and is also 1/4" thick. Since this door has no adjustments, the new gasket and dogs are still tight, and I have to use a rubber dead blow mallet to close the dogs. I dont have to hit the dogs to hard, but the mallet works better than my hand. Ill end up buying a dedicated mallet, and hang it on a hook next to the door.

Both doors have a bronze port light in them, and we decide to polish the port light. I had some stainless steel pickling paste in the shop, and brushing some of that on the bronze took the tarnish right off. It was almost too easy and looked like one of those Billy Mays commercials except for the fact that pickling paste is nasty stuff and will give one a good burning if youre not careful. After the acid treatment, I gave them a good scrubbing in cold water, the put a paste wax finish on them to try to keep the tarnish at bay. Well see how this works out.

Both the AC and DC light switch for the engine room is in our cabin so I can see in to the engine room through the port light without opening the door. I felt like this was important in case something was going on in that room I wanted to see and still maintain the integrity of water and fire tight. It also makes it easy to do a quick check without letting the noise and heat in to the cabin. The light switch for the lazarette is outside the lazarette, in the engine room, for the same purpose of being able to look in without opening the door.

I think Im going to fit some mineral wool insulation in the quick acting door from our cabin. The engine room is heavily insulated, and the door is really the weak link in the insulating chain. Id guess an inch of insulation will knock the noise that will be hitting the door down by 80%.

An update on the fuel system is also needed. I had to re think the priming pump as the chevy pump I had on my shelf was not up to the lift out of the day tank. I found a new Walbro pump on Ebay for not much money, and got it installed. Walbro is a top of the line pump and with just three moving parts, this pump should last the life of the boat. Ill only use this pump to prime either the generator or main engine after I service the filters or for an emergency such as an engine loosing prime, or one of the engines loosing its factory mounted lift pump. This pump is rated at continuous duty, so if one of the factory mounted lift pumps fail, I can always rely upon he Walbro as a good back up. Once I got the pump installed and fired up, it quickly picked up the fuel and filled my filter. I opened the valve leading to the generator, and got fuel flowing to the fuel pump. Just for kicks, I cracked one of the injectors, and had fuel spitting out of the injector. That engine is primed and ready to fire. I might use some street 90s for connecting the pump to the valves, and do away with the loops you see and make things more streamlined.

Im still putting pieces together for the steering system, and should be working on that within a week or so.

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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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