The mainsail on the Tiki Wingsail is very full at the bottom and front of the sail which is great for light air but not good when the wind gets up. In a strong breeze the full shape provides too much power. Here I have rigged a simple 3:1 cunningham/downhaul to flatten the front/lower sail. It only really works on the Tiki when sailing in winds over 15 knots or so, or when you have way more wind than you need. It is useful either to depower the sail by making it flat, or to increase the "slot" between main and jib when close on the wind. I had hoped that it might work as a substitute for tension on the peak halyard (pulling the sail tight from the top/gaff), but a flat sail needs a lot of tension both on the peak and the cunningham.
In this picture you can also see my custom soft pad eye anchoring the bottom of the 3:1, and also the three "head banger" blocks with cleats for the mast halyards (jib halyard, throat halyard and peak halyard, left to right). These are the Ronstan blocks which are rated at 330lbs (150kg) working load - these work very well for the small sails on the Tiki 21, but I wouldn't use them on a bigger boat.
Hey Roger,
ReplyDeleteAre your beams and mast bare (naturally anodized) aluminum? I want to keep my mast bare, but I read somewhere that the natural oxidation is kind of chalky and rubs off on sails, fingers, etc.
Thanks,
Brad
Hi Brad,
ReplyDeleteYes, they are bare alu and they oxidize. The oxidation does mark - but it is minimal. On the other hand the alu mast and beams are zero maintenance, and you can see from the various owner's posts at WB&Fs that beam rot in particular is a major headache. Check out Thomas's Tiki 26 posts.
BTW is the windvane you are working on the Wharram design?
Cool. I will keep it bare then, as planned. I know Kim waxes his mast. Maybe that will help with the marking as well. Do you know, roughly, how much the builder paid for your beams?
ReplyDeleteThe vane is a Belcher MKII like Rory used on Cookie. The book with the plans in it is out of print, and costs about $75 as a result, but that's cheaper than the Wharram plans. If you're interested in a vane, I could take pics of the plans and email them to you. The plans are only three pages out of the whole book! It's easy to build and doesn't use trim tabs like the Wharram vane.
Brad
That is good to know - I thought it looked like Rory's. I am not building one at the moment but will be very interested to hear how your one goes.
ReplyDeleteRoger