Tandem Windsurfing Strand Horst 15/11/15

Another session, 15/11/15, on the Custom Bic Bamba Heineken Tandem (380x65cm, 240liter, 18kg)
We are still in the test-phase, with lots of improvents to be done.
This session with 25kn of wind, gusting up to 35kn the 5.0 and 4.7 wave sails were far from ideal.
Because of serious shallow water restrictions on the spot we had to be careful not to hit the bottom in the vicinity of the shore.
We actually require some small and midsize slalom sails to get the full potential out of the board. SPONSORS ANYONE???
Nevertheless we managed to squeeze out a Vmax of 47.16km/u (25.46kn).
The race for 55km/u (30kn) is on. And we are pretty certain that this is possible with the right adjustments like sails, fins and footstrap-positions.
After this it's time to look for a smaller, narrower, lighter and faster rocket....

[gregkelson]

Hi Guys, it is great to see another home made tandem.I started adapting boards in the 1980's and eventually took a K-Bay Tandem to the Weymouth speed trials - 3.7m long and 28cm wide, very hard to get going but superb on the plane.I now have 3 tandems, a Fanatic Mega Cat,  Tiga Race and a production F2 tandem all from the 90's.  In my experience the decision of where to put the masts is dependent on how comfortable you want to be.  Generally I have left the rear mast in its pre-conversion closest to the tail position.  The front mast then goes as far forward as you dare, obviously the greatest length between masts will make sailing safer and gybes more likely.You can buy lovely, well cared for race boards for 99p on ebay, my favourite brands are Fanatic and Mistral - big chunky boards with hard rails.My Mega Cat had virtually no structural integrity in front of the mast track so anchoring the new track was challenging.  It is fun to sail in most conditions because of its relatively high volume at 250 ltr.The Tiga Race is the fastest  peaking at 27 knots August 2016 in Christchurch harbour UK.  On this board I did a full conversion scrapping the existing mast track and moving the rear mast as close to the tail as I dared.The F2 at 360ltr has not really had a good test yet - I am still trying out fins, 36cm is the longest length I have ever used but with lots of sail area you need a lot of fin area.II don't know why there are so few around - they are great in all winds, my kids all started off on the front of a tandem.  Having said that there are many people who say they would love a go but never quite take the plunge....too much thinking about what could happen if something went wrong I guess....

[sorywal]

Hi Guys,
Nice Sessio. I also like tandemsurfing. I modernised an old one (470cm/ 30kg) together witch a profession boat builder. He gave me some "tuning"- tips. Here are some from the "pro" to support your project:
- For more Speed: make the Board LONGER! not shorter! Perfect size is around 450cm. Keep in mind that the ratio between length and wide of the board must be min. 1:8 to make the board plane.
- Enforce the center with 2 x-ply Stringers (6mm/ 300cm)= more Stiffness means better Performance
-Reshape the bottom: Build a small "Kiel" about 1-2 cm with epoxy putty under the Board where the Frontman stands= V- Shape means more Grip and less drifting
- Shape the Bottom of the board flat at the position of the Frontman.
- Build in a Tuttle Box: Min Fin size Weed 40 cm! offers Stability and Performance
- Use a Layer of Carbon to enforce the bottom: the effect is great!
- Enforce the sidewalls with 2-3 layers of UD glasstape ( 200gr/m2); You will seal the ASA Sidewall against water and you get a stable Frame around the board which offers great stiffness!
- Try to surf with bigger Sails (7 m2 rear, 6m2 front) in lower windconditions= The larger the sails the larger the "doubledecker" effect between the Sails; better performance in gusts

Trust me: your board will get heavier (7-8kg) but regarding the sailrange on the top of the Board its just peanuts! After reshaping my board we got 5-7 knts faster!

Hang loose!