Biocide free antifouling

Fouling (marine growth on the bottom of boats and ships) is a big problem for shipping worldwide. Excessive growth of barnacles, algae etc. increases the friction between hull and water and therefore leading to high fuel consumption and unnecessary GHG emissions.

The conventional solution are toxic bottom paints which slowly leach microplastic and biocides into the water. This is a big problem for the marine environment taking into account the thousands of big and small ships out there.

The Dutch company Finsulate has invented a biocide free (non-toxic) antifouling solution. Manfred Bauer, the local distributor of our area has invited us to an application training.

Innovations like this have the potential to make a real impact. We will trial the Finsulate material and report regularly about the results in the future. In a first step three identical test bodies will be deployed at our mooring: One equipped with Finsulate Seagrade, one with conventional Ultra 600 bottom paint and the third one without any specific antifouling measure.

Check out and for further information!

2nd Birthday

On this day, two years ago, the first post was published on Thanks to all our supporters we’ve come a long way in these two years!

From the very first sketches and calculations over various model tests and real size mockups we’ve made it through endless hours of laminating fiberglass, gluing, sanding and painting. Now we have a beautiful sailing proa and can start to work on the real mission: climate action now!

First Sea-Trial

Last week we left Kiel for the first longer sail on Proasis. Our triangular test course brought us from Surendorf to Marstall (Denmark) to Schleimünde and back to Surendorf. The total distance of approx. 60nm took us two and a halve days due to very light winds (sometimes even no wind).

We spent the nights on anchor exploring places where almost no other vessel can go: Without leeboard and rudders Proasis has a draft of only 15 cm. This allows to anchor in knee-deep water.

On anchor in 30 cm deep water right next to a sand bank.

We are very happy with Proasis’s sailing characteristics. As soon as the wind is above 8 kn she’s easy cruising at 4-6 kn. Top speed at about 15 kn of wind was 8 kn. In lighter conditions she feels underpowered but thats not a surprise, the polytarp sail is only 13 sqm. We might get an assymetric spi in the future.

Wake at 7-8 kn.

The helm needs not much attention, the tiller is simply fixed in a certain position and the boat keeps on sailing on a steady course for hours.

The white line is our adjustable auto pilot.

Proasis sails upwind well at a tacking angle of 115° (could point higher but would loose speed). Thats not exactly where we want to be (100° would be nice) but a good starting point taking into account the cheap and wrinkly polytarp sail and the leeboard issues (see below).

Three upwind legs, the tacking angle can be estimated. Will be optimized in the future.

Shunting turned out to be a very simple and reliable maneuver (at least in winds up to 20 kn, havent tried in stronger winds yet). It never went wrong and can be done singlehanded without any issue. The Rudders are inverted almost automaticly by pulling one line for about 2 seconds.

Ready to shunt the sail. A video and detail explaination of the entire process will follow soon.

The most important downside of every shunting vessel is most likely jibing downwind. Instead of simply shifting the sail from one side to the other, a proa has to come upwind, perfom a shunt and bear away again. Compared to a simple jibe on a conventional yacht thats very slow but we take it as part of the game 🙂

Sailing intoo the Schlei mouth, thunderstorm ahead.

Living on proasis is quite comfortable for two. During the entire trial we never went ashore. Sailing, eating, sleeping and repeat.

Messy bunk, we need to optimize the interieur to keep things organized.

Despite our very pleasant sail, Proasis is not perfect yet. Following tasks are on our list for the next trial:

  • Leeboard: The foil shape is to thick causing lots of drag and poor performance. We have to make it thinner.
  • Mast: Needs some stiffening, we’ve observed to much flex.
  • Sail step: We have to reposition it sligthly further forward to improve the balance of the boat.
  • Interior design: We need more cupboards, hooks ect. to organize our stuff.
  • Electric installation: We have non yet. We plan to install a solar panel, battery, navigation light and charger for chart tablet.

Proasis Launched!

After 2 years of designing and building proasis, finally the day has come and she touched the water of the Baltic Sea for the very first time!

This was a very special moment for everyone involved. We would like to thank all the supporters who helped to assamble her and put her into the water and the sailing department of the STS Surendorf. The launche was a great community effort and a prime example what a group with a common interest can achive.

Rudder Mounts under Construction

As promised 2 weeks ago some more detailed shots of the rudder mounts:

The rudders hang on triangle mounts , one on each beam. The forward one will be rotated under the tramp when sailing. Hopefully this will keep the rudders away of waves and avoid the splash often seen on proas with rudders at the forward end of the leeward hull.
Rudder mount folded under the trampolin for a left tack. The mounts will be able to kick up to the other side as well to some extend in case of ground contact.
The rudder foils (old F18 daggerboards, made longer, see yellow part) go into cassets. The foils can be pulled up to adjust the wetted surface and the depth.
The cassetts are bolted to the triangle mounts. One of the very few times metal is used on proasis.
This is how everything will go on the beams. The cardboard is a model for the tiller mount (still under construction).

Windows glued in

Two of four windows are glued in. We’ve cut them with a jigsaw from polycarbonat (makrolon) and glued them in with a special glue for the wind shields of cars. Worked really well and no screws required.

The remaining two windows will go on as soon as the weather switches back to summer mode.

First to windows glued in. Hold in place by briks.
Preparation is everything!
Frames carefully sanded and taped.