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December 27, 2015

THE MECHANISM OF EX LEX LEEBOARD/HIKINGBOARD METAMORPHOSES

As a leeboard the board can swing aft and forward on a traverse axis a M16 bolt. Converting the board to a hiking board I swing it as far forward as possible out of the water. Now I can reach the tip from the fore deckhouse.

I fasten three control lines to the tip. Their function will be to slide out three lead weights of 6 kilos each.

After that I swing the board down to its deepest position. In that position I connect a hinge with a rolling longitudinal axis. The hinge is a figure 8-rope hinge. Rope hinges are very strong, resilient and flexible and there is no pin or axis that you have to fit, just get the rope around and haul in, a good thing on a boat moving in waves.

That done I can remove the bolt.

Now the board is free to swing outward, but not forward and aft.

A downhaul fixes its position.

With the help of a halyard connected to mast standing off center I raise so that it becomes horizontal like an airplane wing (The angel of attack can be made so that the wind creates a downward force. The board is like an airplanes wing, asymmetrical.)

That done I can now with the help of the control lines slide out the weights. How many and how far out will depend on the strength of the wind and how hard I like to drive Ex Lex.

This is nothing for a skerry cruising boat, they change tack all the time. On my planned trip, the time scale will be very different. For example at latitude of the Cape Verde island I will have the trade wind in on my port side about five degrees north of the equator I will meat the south east trade wind head on the boat will be hard on the wind trying to clear the north east corner of Brazil. At the latitude of Bahia my sheets will be eased the wind still on the port side. Hopefully I do not have to change tack before the latitude of Rio, a distance run of maybe 40 degrees of latitude and thousands of miles probably nearly two moths of time. Weeds will be growing on the starboard freeboard if not scraped away.

Below is a nice weather link illustrating the globes weather pattern.

https://www.windyty.com/?8.494,-11.250,3

Getting the board back to prevent leeway I reverse the operation. Surrounding the nut that holds the bolt that functions as the traverse axis is a short length of pipe that slides into the boards bearing, fixing its radial position. The pipe is shorter than the board is thick. Into it you can also if there is a need insert a bar and use it as lever to aligne the hole in the board to the pipe.

Once there it should be easy to insert the M16 Bumax stainless bolt that fixes the boards axial position, thus it becomes a two step operation. Thanks to this arrangement I do only have to keep one thing in place at the time. I do not have to line up nut, bolt and leeboard simultainiusly.

To be continued…

Regards Yrvind.




December 15, 2015

MASTS & HIKING BOARD

Today I have collected three experimental masts from Marström Composite.

Below is a picture of them in the company car.

On Ex Lex

and front vieuw

Two of them have a total length of 2.5 meter. The weight of each is 3 kilos. They stand 2.05 meter above the deck and are selfsupporting. Its Europe dinghy carbon fibre masts ballasted with glassfibre.

Their maximun diameter is 64 millimeter. I hav cut them down to size and grinded away the track. A lug sail do not need a track.

The long, light wind mast, is 3 meter and weighs 3.5 kilos.

More excact weights are below.

There are three masts and four standing mast position and places for them on deck in stronger winds. That gives many combinations. I am sure that Ex Lex will tell me how she likes to be rigged in different weather conditions.

Even an old man should have no trubbel to handel a 3 kilo, 2.5 meter long spar.

Hiking boards are an old idea. I used one succesfully on Anna 1967 and 1968 when I sailed her from Sweden to England.

There is also an video on you-tube showing me hiking on Anna. (yrvind+anna)

https://www.youtube.com/watch?v=swMiLvZ1r10

Abowe a screenshot.

Some parts of the voyage was quite ruff. Often I was sitting out on the hiking board seeing Anna disapear below the waves only to come up, a little later, with a smile on her face.

Michalak and other small boat designers bolt the leeboard to the side so that it only can swing back and forth. The Dutch leeboard swings also outwards, “the broken wing” on the windward side. Benno from Germany sugested that with the Dutch type of leeboard the windward one could be used as a hiking board.

Obviusly there is a lot of problems involved if they are going to be used ballasted, offshore, in strong winds. That is when more stability is mostly needed. There is the ever present risk of capsizing. The hiking/leeboard has to be fixed as good as an keel.

I belive that I have solved most of the problems involved and I have begunn to schetch a bit on my model to develop the idea into a usefull and functional device.

The model with hiking/leeboard

From the front

To be continued…

Regards Yrvind.




December 12, 2015

THE AFT DECKHOUSE

Here are some pictures of the aft deckhouse during construction.

A waterproof bulkhead is put in place.

I am not made of suger, but I like to keep the water on the outside. The below pictures show the part of the ventilation system separating water and air, the boat on even keel.

The draining holes. I use two water traps. Should the first one not suffice there is a secound.

This is how I did it on YRVIND.COM the yellow boat 2010.

A U-tube lets out water but not air. Below the box and U-tube painted.

Below a schetch of the principle.

On Ex Lex 2015 the building is simplified somewhat. I use triangular channels. Its simpler to make and no sharp edges, it also is stronger structurally even though I do not think the deckhouse can be damaged without that triangulation.

The “U” in place.

Looking from below the drain hole can be seen.

The channels sides in place, seen from above.

From below.

A shaky schetch of the idea. Hope it helps.

One more picture, the deck is coming on.

To be continued…

Regards Yrvind.




December 3, 2015

MY POSITION

Hi Manie and other small boat sailors.

I reside in VĂ€stervik a small town by the sea, a three houer drive south of Stockholm.

My phone number is +46 70 620 05 50. 20:00 to 22:00 is a good time to phone as I then usually stopt working with the wonderfull epoxy.

Regards Yrvind




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