November 28, 2016


The main deckhouse and ventilation is done.

Below an illustration by Pierre Herve.

In bad weather a mixture of air and water enters the ventilation cowl, like in a Dorade box the water is separated. In Exlex there is a water seal, like in the drain pipe under a sink. Thus all the air is ducted to the inside of the boat.  The Dorade box has a large volyme compared to the diameter of the cowl – if one can compare a surface to a volyme – should plenty of water come. As a back up there is a secound large volyme box.

The clean air now descends through a channel to the bottom of the boat, then crosses to the opposite side.

When the boat capsizes there is always some part of the ventilation system above the sea surface and as water cannot rise above its surface no water will enter the boat -same principle as in a centerboard case.

Some water that has entered the ventilation system may drain in the navigation cabin/ lunch room where it is harmless and will be taken care of by kajak pump.

There is a mirror image of the system on the other side. One side for incoming air the other for used outgoing. due to space restrictions I do like to have the crossings in the same plane therefore one system is crossing at the deck level the other at the bottom level. Therefore the two vertical channels are on the port side.

Below are some pictures.

One channel under construction

Vieuw from hatch. The two inlets one on each side.

Viuw from aft window looking into sleeping room through waterproof hatch.

The main deck house. The solar panels are temporarily there.

To be continued…

Regards Yrvind

November 5, 2016


Here are the latest pictures.

Below is the lunchbox or foodbox with food for about a week. The picture shows the six one-liter bottles. Seven would have been better, but such was unfortunatly not the geometry. Later musli and sardines will be added.

Close upp of the bottles that got there own compartment as not to rattle around. Its a good fit. The peelply has now been peeled and the stick that holds the wall in place taken away.

In the front of the boat the small deckhouse is now laminated into place and a towing bollard and four strong points are installed.

Close up.

The strongpoints are boulted by 4 M6 boults good enough to lift the weight of several Ex Lex boats.

Inside are 3X4 cm backing washers.

The towing bollard is fastened by 5 M6 boults and 4 4.8 mm seelf tapping screws

There are also several extra laminations inside and outside to reinforce.

To be continued…

Regards Yrvind.

October 25, 2016


The windows in the forward deckshous are now in place thanks to Petter and G A Lindberg ChemTech AB.

I chose silicon becouse it is resistent to UV-light and weather. Butul and other componds may be stronger, but silicon holds 20 kilo in tension at each square centimeter giving a total strenght per window of about 4 tons wich is ample for a boat of about one ton. Also unless I go crazy the the force is unlikely to come from inside the boat.

Below are some pictures click once or twice to enlarge.

Rubber distances are placed to get the silicon acces to everywhere. This is important so that no hard spots get in contact with the tempered glass.

And last picture. Petter can relax after my harsch supervision.

To be continued…

Regards Yrvind

September 18, 2016


In contrast to a centerboard can a leeboard be angled to give an optimum perfomance.

Consulting Matt Layden who knew a bit about the subject I have chosen 1 degree toe in and 12 degrees outward.

Tjat the board may rest agains a flat surface I have used sandpaper on a big particle board. Heavy work, but good results. Foto below.

This is how the angels came out after lamination with 8 layers 450 gram stiched glasfibre.

Leeboard up. The clamp will be replaced by a M 20 bolt and diameter 100 mm, 6 mm thick washer.

Leeboard down. This is the starboard side. Port side to be done.

To be continued…

Regards Yrvind

September 8, 2016


There has been some progress. Things are finding there places.

Below the forward mastholders.

and aft mastholder. It was meant thet there should be one on each side also aft but unfortunatly it interfered with the two stearing lines, so one it is. It should have been at center but that interfered with the locker for the 15 kilo SPADE anchor so it is a bit offset to port.

There will be solar panels aft the main deck house. I do not like to walk on them so a rubrail on each side is added to take me back to the cockpit with its sculling oar and swim ladders.

The hardware to hold the rudders and yuloh is now fabricated.

The picture below show the mock up for the control lines.

My intention is to use the twin rudders in lieu of a drouge by angling them out. I must thus be able to control them individually. The idea of a connecting bar did not work to my satisfaction.

Becouse the rudders are at the side the tiller have to be angled at 20 degrees or so invards to give the lines scope to pull.

The control lines run the lenght of the boat making it possible to adjust them even from bed.

Below is a picture of my system for microadjusting them using a rigging screw. That system is sliding so that when courser adjustments are desired the thing can be mowed back or forth on a track. To get the lines from outside to inside seals are used running in pipes more about that later.

The rudderheads are now made and installed. They are about 5 cm thick. I could not use my drill press.  To be able to drill stright I looked at the mirror image of the drill in the fitting, when it was lined up with the the drill I was at right angle. Picture below.

Below is a picture of the rudders folded up.

The picture below show the rudder in the down position. The nut on the 20 mm bolt is welded to a wheel thuse making it easy to loch the rudders in the desired up or down position. The wheel is secured with a piece of string. Click on the picture once or twice to enlarge.

The rudders are rather large to get a lot of surface when using them as a drouge. Its nice to have control when running before a gale.

Here is a picture of the yuloh

Bengt Linden a supporter from Stockholm have also been visiting me.

Below next to the yellow boat that I sailed to Martinique with 2011.

Below inside the boat.

Bengt is bigger than me.

To be continued…

Regards Yrvind

August 26, 2016


To invent a small cheap functional sextant capable of measuring any angel up to 90 degrees and accurate and rugged enough for life raft use my thinking went like this. I imaged a fixed angled Bris sextant, then one more to the left having a slightly smaller angle a third one to the left of that with an even smaller angle and so on down to zero. To the right I imaged a series of Bris sextant their fixed values kept increasing up to 90 degrees. After that I imagined the steps between them becoming smaller and smaller. After that still in my mind I glued them all together. Now I had a thought model of the finished product, one long sextant with twisted mirrors.

I made the first test by taking two strips of tinted semi reflecting acrylic glass and putting them together, one on top of the other. I joined them in one end, and then I twisted them at the other end to the desired angle and fastened them so together. I added a scale and a cursor to make reading easier because the human eye cannot focus so close. I have the option of adding shades to the cursor.

When taking a sight I hold the instrument close to my eye in a horizontal position, looking through it at the horizon. To move the image of the sun up and down I move my instrument sideways. When the sun is touching the horizon I note its sidewise position in relation to the scale and time it.

The next step is with the help of my position and the time to calculate the suns altitude. That way I find the corresponding altitude of my instrument at that point on the scale. I repeat the procedure for a few different angels.

As there are an infinite number of different angels there is no way I can calibrate them all, but that’s not necessary. It is enough to calibrate a few well spread out spots and make a table of them. To find any other angel I extrapolate or interpolate.

There is two ways to achieve the desired accuracy without a long and cumbersome instrument. One is to make a set of shorter ones, for example a set of three 30 cm long instruments with angels 0 – 30, 30 – 60 and 60 – 90, corresponds to a 90 cm long scale giving 1 centimeter for each latitude.

Eighteen instruments each 30 cm long will give a total length of scale of 5.4 meter long. Still the will require less space than a conventional sextant.

The other way is to make one instrument, like the Bris sextant with several mirrors that crate several images of the sun, spaced to the desired angels. It’s a neater solution but iterations or calculations will be needed to achieve the desired results.

The Bris Sextant and Yrvinds Survival Sextant are both interesting products and they complement each other. The Bris Sextant is extremely small and exact, but like a set of sockets has only fixed values. Yrvinds Survival Sextant is not so exact but can measure all altitudes a bit like an adjustable spanner.

Me, I have leave these experiments for time being to focus on my boat Ex Lex. Boatbuilding is also a lot of fun as is sailing the finished product.

ABOUVE. Long version of Yrvinds survival sextant. To take a reading, slide the sextant sidevays, that will move the sun upp and or down. When the sun touches the horizon time it and note how far  sidevise the sun is on the scale. No moving parts.

To be continued…

Regards Yrvind.

August 16, 2016


Same years ago I invented the Bris Sextant as a backup. It’s a small cheap functional instrument. Its extremely accurate, much more so than the ordinary sextant because it uses a number of fixed angels instead of a continues scale, but like the ordinary sextant it needs accurate time to give you a fix.

Photo above Bris Sextant in my right hand the ordinary in the left.

Time can be lost due to lightning, if there is a fire onboard and you most abandon ship, and for many more reasons such as the unlikely event of our civilization braking down and the time signals stops.

Fortunately latitude can be found without time by observing the suns altitude at noon.

The chronometer was invented only after most of the world had been explored so most discoveries were done without synchronized time. Therefore the explorers could not find their longitude. The going was though. They overestimated how far they had gone. Their latitude they could check, but not their longitude, hence maps from that time show the world much fatter. See illustration below.

To find ones destination without synchronized, one has to sail north or south to the latitude of the desired destination, then sailing east or west, constantly sounding and with a sharp lockout until one arrived at the desired destination.

Of course I could get an ordinary sextant but they are complicated and prone to errors, so I thought if I could invent a small cheap functional sextant with a continues scale, but without moving parts it would be a good thing.

An other picture

Photo above the survival sextant with its continues scale and its cursor.

Me with the first experimental model. I used it to testi if the new principel worked. It did and does but its accuracy is good enough for survival use.

I will soon publish an explanation of its principle and how to you use her.

To be continued …

Regards Yrvind.

July 29, 2016


Here is a mock up of the idea of the rudder control.

Ex Lex has twin rudders. The reason is mainly for ease of making the boat stear itself downwind but also for using as a drouge when having them in V-position each one angled 20 degrees out.

I hope to be able to stear from any position. a stearing line will run the inside perimeter of the boat. In addition there will be control lines fron the two hatches to V-position the rudders for breaking (car owners think Ackerman).

To achive this the tillers have connecting bar, but are not directly conneected to the bar but to trawellers sitting on the bar.

Normal stearing is done with the trawellers in zero angle position. When I like to brake the trawellers are adjusted towards the center and thuse the rudders are angled out. The lines controlling the trawellers are run to the rudder accis that they may not be affected by stearing.

This is a first try so I can only hope that it will work.

Some hardware is on its way.

Above: The tillers parrallell for normal stearing.

Above: The tillers in breaking V-position.

Above: The mock up tiller head on the mock up traweller.

Abowe: The mock up stering lines moving the connecting bar.

Of course for those with a well lined wallet it can all be done more complicated using electronically controlled electricity.

To be continued…

Regards Yrvind

July 16, 2016


Lenghtening the boat has giving me more storage space. The new hatches can only be reached from the outside. I will only transfere goods in fine weather but it is important that they are waterproof.

The picture below shows how they are tested upside down before being installed. Ping pong balls are floating in the water.

Click once or twice to enlarge

Also I have now shaped the 4 fins, 2 rudders and 2 leeboards. They are the same shape and size as to replace each other in the unlikely case of breaking. The tipp part is laminated of five 10 mm plywood laysers.

To be continued…

Regards Yrvind

July 14, 2016


I have two visitors. Falcon a yachtsman. He spent his first week in a hospital. Then he spent a week in a flat, then one month old he crossed his first ocean. He continued to live 18 years in the boat sailing the eternal endless sea. Now he is here to give me a hand.
Miki is also here. He is from Austria. He helping to modelling my boat in Rhino, like he did with Yrvind Ten.
I took the opportunity to ask my visitors to give me a hand in weighing Ex Lex.
We put everything ready into her, masts, spars, leboards, rudders, hatches ecetera. It came out to 415 kilo. Everything is strongly made and it has been a while scince I weighted her, so it was a releif.
Miki did a calculation in Rhino of the displacement and found that she will float nicely at 32 cm draft loaded to 1100 kilos.
That will take care of the weight problem I think.
Below some pictures, Falcon in the photo

To weigh the boat I hang here in two ropes and add the forces. The picture below show the wheight of the back rope.

This little calculation shows the wheight estimate.

Boat at present 415 kilo

Betteries 75 kilos

150 more kilos to finsh boat

Food 250 kilo

Water 100 kilo

Miscellaneous 100 kilo

Total 1100 kilo

I reserve the right to make miscalculations.

To be continued…

Regards Yrvind

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