Wow – this boat is something special

22:nd of april is Yrvinds birthday. That fact gave me a reason to visit him in Västervik and to see how his project advanced. This winter I have talked to him a lot on Skype and he had given me vivid reports about the project. So, I thought I was prepared of what was waiting. But in place in his workshop I became surprised. What I saw gave me a Wow feeling – this yellow creation is something special. I had plenty of time to study the boat since the workshop would be the place where I should sleep over the night. In my bed on the floor I was studying hers shapes and many thoughts passes through my head. That she i extremely strong is for sure, no doubt about it. But how would she perform under sails. The boat weight fully loaded, is about 1.2 ton and she is only 4. 8 meters long and 1,3 meters wide. She have no keel, just chinerunners attached alongside the hull. Will this concept work on a small boat with a heavy displacement and relatively small sails? Will his ideas about self steering be functional on a boat with this kind of “tiller” construction? Anyway, it will be very exiting to follow Yrvind when he launch the boat and start testing her. Hopefully this will happen very soon.

Many pics below

Webmaster – Beppe Backlund


To protect the boats bottom when taking the ground as the tide goes out and when dragging her up on a beach I have fitted a bronze shoe.

Bronze was chosen because it is easy cast, has good marine corrosion resistance is antifouling as it contains 90% cupper and is quite heavy thus also acts as good ballast.


Fastening it to the boat presented a challenge. Many boat builders use NM flexible epoxy 705 when attaching ballast keels to sail boat hulls as it is a high quality thixotropic flexible epoxy. What is not often recognised is that to press down the thixotropic requires quite a force if the surface is large. That’s no problem when you have plenty of strong keel bolts to tighten and a small surface. On mine boat it is the opposite a large area and only three 3/8 bronze bolts to the lightning conductor.

Each square centimetre required three kilos of pressure. With an area of almost one square meter or 100 by 100 centimetres I realised that I would need about 30 tons to squeeze out the epoxy, obviously not a practical proposition. After consulting the NM epoxy chemist it was decided that I should dilute the flexible epoxy with laminating epoxy to the desired degree. That would change the rheology to make the mixture more fluid but still flexible enough.

To find out the right mixture I built a crude apparatus and made some tests.

A piston with a certain area and weight was used attached to a rod which could slide up and down constrained by simple wooden bearings. After some testing I found a mixture of 55% flexible and 45% laminating epoxy was just about right.

First I was mixing the flexible resin and its hardener, and then mixing the laminating resin and its hardener, thirdly mixing the two mixtures together.

The job had to be done quickly because once the mixing was started there was pausing. I found six volunteers and ten a clock a Saturday morning we started.

Steel rods were in place to guide the bronze into the right position.

The mixture was spread out. The boat was lifted with chain hoists to take the weight of the bronze.

About 200 kilo of lead and cast iron weight was added to the 126 kilos of the bronze. The three bolts to the lightning conductor were tightened. The epoxy mixture flowed out nicely. The heat in the room was turned up to the maximum. The operation was successful. I thanked my volunteers they had done a good job, they were all needed. I slept well.

Yrvind at Hamel Sails

A boat designed by Yrvind is extreme in all ways. First it´s very small and it should handle extremely rough conditions. It should be safe and provide protection for its crew. It should carry heavy load and should be able to sail in any weather conditions.
On top of that it should survive a rollover. A challenge for Yrvind was to find a sailmaker who understood his requirements and that is also a good interlocutor.

In this film Yrvind meets the guys at Hamel Sails. The film also shows how a sail is made. If you have a fast internet connection, you can view the movie in full screen HD, 720p.