Yrvinds 2.7 meter or 9 feet long mast came out of the autoclave well cured and in a perfect shape. Thank you everyone at Marström forall the help. Here it is the mastshop, being tested for strength by our strong man Mario. If it can survive his 150 kilo ( 330 pounds ) of muscles I dont think I have to worry in the Southern Ocean. Presently Im working on the masts three goosenecks. Besides the usual one for the boom my rotating mast has two on the leading edge as well. One for the supporting spar and one for the whisker pole. The goosenecks also serves as mast steps. I have no halyards as its easy to reach the mast top.

Its lot of fun to at Marström and there is always exciting projects going on. Due to rapid expension and many new orders we need plenty of more engeniers at least two right now. If any of my readers are familiar with the computers and the program “solid works” please apply for a job. For more details visit our webb page MARSTROM.COM mention my webb page.


After nearly a week of putting the prepreg material in the mold; all the unidirectional, the 90 degrees and 45 degrees and the reinforcements is finally in place, as is the peelply and and vacumbag. Sam my master is checking for leeks.

Sam is satisfied. He assures me everything is going to be fine.

She is ready for the 35 meter long autoklav. With a 2.7 meter long mast I don’t feel I use its full potential.

Here we are getting up speed.

She is nearly in.

Thomas is closing the heavy lid.

and locking it.

Fredrik the Boss is chacking gouges and the tempratures of the inside surfaces of the mast the outside surface and the temperature of the compressed air inside the autoklav.

Finally I watch all the gauges while reading a yachting magazine. Everything worked perfectly, during the night she will cool under pressure in the autoklav and vacum in the bag and I will dream nice dreams. a big step forward has been taken.


The picture above shows a model of the rig. Its a kind of biped. Two legs is stronger than one, they have wing sections to reduce wind resistance and make the sails more efficient. In heavy weather the sails will flap about less.
Also as the forward spar, the one supporting the jib in contrast to a wire can take compression the shrouds as seen on the model can therefore be placed forward of the mast allowing me to let out the boom about 135 degrees instead of the normal about 80 when sailing downwind. This helps to prevent jibes. With the boom forward if the mast the boat will travel downwind steady even in bad weather.

Below is a picture of me and my Master Sam teaching me how to cut prepreg.

Here we are with the mast mold. It is five meters long, long enough for the 2.7 meter mast and the 2.2 meter long forespar. This is my usual luck. Should I by chance run out of luck my philosophy is: it is better to have bad luck than no luck. Finally for those wishing to hear me speak in my native Swedish there are now, on this website under the heading “various” an audio file in two parts. Enjoy.


The picture below shows a second mock up of the rudder head with the rudder blade.

Below is a close up of a new and better line arrangement. Yrvind has no tiller. It saves weight and gives me more space on deck.

On passage I let the boat self steer with the help of feed back from the sheets. The lines from the sheets run in my case directly to the rudder. It is a simpler arrangement. An other advantage is that close to the coast it is handy not to be tied down to the tiller. With the steering lines I can walk around on the boats deck using them as remote controls. Whith the help of the steering lines I can in good weather stand on the fore deck looking at the bottom when navigating in shallow water. If I like to do that.

In the meantime the real rudder blade and the centerboard are being faired in Marströms mast shop. In the background two centerboard for the Volvo Ocean Race boats can be seen.


More good news, Göran and Per has given go ahead with building my spars. Here Göran and I are with an experimental mast for my boat. It is a 2.7 meter long piece of an Ice boat mast. They are usually made of glass fiber. I consider doing the same. The disadvantage is that it is about two to three times as heavy. The good thing with glass fiber is that the mast will be extremely flexible, like a fishing rod, which is good considering capsizes and pitch poles. Also it will allow me to place an VHF antenna inside the for the AIS sponsored by TRUE HEADING. Inside the mast the antenna is protected from weather and it gives no wind resistance. I consider it to be essential to reduce all kinds of resistance as much as possible. On a small boat powered only by wind and muscles you have very limeted resorces and have to be as efficient as possible.

Next week 4 to 8 November I be in Stockholm giving a talk together with Thomas at ABF ( see under lectures ) Also I will be at the Stockholm boat show looking for sponsors. Therefore during that time no work will be done on the boat.


Jakob Alander has kindly helped me to plot the stability numbers below making it much more understandable. As can be seen there is no need to have a deep keel to get positive stability through 360 degres. Matt Laydens Paradox and other small boats with similar height to beam ratio and a low enough center of gravity confirm this.


Here are some stability calculations and other numbers who Guy Lilljegren kindly has provided me with. There are three sets for center of gravity for 5, 10 and 15 centimeters above the waterline. Hopefully the center of gravity will come out at 10 centimeters above the waterline, but only the Gods know for shore. The numbers are really too small to reed but if you click on the pictures, first one time, them again, they get bigger and bigger.


I have been very fortunate in that Quantum Sails Loft in Kungälv have undertaken to sponsor me with sails. From previous experience I know that the do an excellent job. Below is Patric sewing on a sail to Yrvindaren. (see photos)

Here Henrik is showing all 0.5 sq meter of it.

Quantum sails will sponsor an illustrated lecture in Göteborg on next Wednesday the 29 October 6 30 pm. If you are interested in hearing me talk about my voyages take contact with quantum sails phone 0303 10818 The talk will be in Swedish.


The last work on the interior is now done, it was getting some NM-epoxy on the underside of the shelves. To make the epoxy flow in the right direction I turned the boat upside down and on its sides.

I also weighed her. She was at 250 kilos or 550 pounds found lean and strong.

After that I started on the lower aft deck. Here I am fitting the frames to the deck curvature which is 85 millimeter high on 1320 mm beam.

Here looking aft, having removed the pattern.

The frames are ready to take the Divinycell which for the deck and deck house I use a thickness of 30 mm and a density of 80 kilo per cubic meter.

After laminating the inside with one layer of 600 gram quadruple glass in NM-epoxy I bend with the help of lead weights the panel over the frames.

To be continued…


Kåre Ljung an areodynamiker one of Ridders disciples, now working at Marströms, has helped me to modify a NACA-profile to suit my demands.

Here Gösta Larsson who kindly has offered to help me mill the rudder and CB Divinycell-core is programming his NC-machine to do the job.

Here Gösta is adjusting the machine.

Here he is advising me how to watch the machine mill the divinycell to size. The tolerance of the machine is better than a hundred of a millimeter. Fare more precise than what I need.

Here Im watching the machine doing the precision work. Thank you Gösta and your company Larsons mekaniska i Hjorted.

In the meantime Börje from BT-Hantverk has done the rudderfitting. Shown below.

Here I am doing a bit of mockup with the stearing lines I use instead of a tiller, saving a bit of place on my small aft deck. Tacking care that I get a god angle of the lines also when the boat is going backwords and there is a reverse pressure on the rudder.

Sad comment. Even in our little quite town of Västervik there is vandals, bored people. Here someone has destroyed our nice little clock in the park outside by throwing a stone at it.
One of the good things with siglehanded ocean sailing is that you are fare away from the vandals. Life on the ocean wave is freindly.