Hi Tim,
I've done nothing with your old hulls except put them in the back yard while I try and sort out the techniques for making the beams and rudders and possibly hatches.
When you get round to the rudder shafts, give me a call as I should have the technique sorted.
Are you still going with the same design?. If so,make sure the bottom is connected to the sides before bending. The builder tried to join after bending and stuffed up the join, leaving a significant chine and fairing problem. The technique of half glassing polycore and pressing grooves to control the bend should work with that design. I feel that with your background, you should have better quality control.
I am not sure that there is that much more complexity for a rotating mast. The main difference is the cost of the bearings.
The hinged junk rig set up that Mike has pointed to comes pretty close to what you are after but doesn't have the extra bolt rope set up for adding sections. I don't really think that it is worth the extra hassle as the connectors are a possible source of failure. Stitching can always be undone and new sections sewn in. There is the difficulty of how to make sure the sections don't buckle under the compression with the lines to the ww hull. I think this needs very robust hinges or extra strings to the centre of the hinges
--- In harryproa@yahoogroups.com.au, "kimberlydreaming" <clairebarker5@...> wrote:
>
> Hi all , we are having another go at building a livaboard Harry ,most wont know that we were getting one professionally built last year only to have the builder string us along and then fold up taking a lot of our and others money with him. Anyway weve tried to kick the idea but it just wont go away so we are planning a fulltime build ourselves around june july next year.
>
> Anyway i would really like a wing sail so heres the deal, if the group can come up with something that fits my parameters i will put it on my boat. What i dont want however is long and convoluted discussions on foil shapes types center of effort etc. This is purely about "the system" the actual means by which we shape the soft wing sail ,the mechanical bit.
> A few considerations 1 it must be simple
> 2 cheap to build
> 3 easily hoisted and lowered
> 4 single skin(can have doubled leading edge
> 5 able to reliably form and hold the desired shape
> 6 as easy or easier than a conventional rig for a cruising couple to use.
>
> What id also like to lose is the complexity /expense of a rotating mast/masts
>
> As a starting point at the moment my ideas are, multiple hinged battens attached to hoops(think tennis racquet or snow shoe) shaped like an aerodynamic leading edge which wraps around the mast . The battens and hoop would have bolt rope tracks incorporated into the top and bottom surfaces which would allow flat rectangular sailcloth panels with bolt ropes sew into the edges to be threaded/hanked on. This would allow spare panels to be kept and replaced when needed. The hoops would rotate around the mast and would be formed so that they projected some way in front of the mast to add a little more balance (think of the pivot point as at the throat of the tennis racquet) The hoops would either flex around the mast and be tied bolted ie the hoop is under tension or they have a small removable section to allow removal of the assembly from the mast.The battens could be nylon webbing(as for ratchet straps) with matching spacer blocks either side bolted through, the shape and gap of these blocks sets the precise camber of the batten.The spacer blocks would have a groove so that when bolted together they either clamp the bolt roped edge of the sail panel or form a track that the bolt rope edge can thread through. Sheetlets in dyneema would run froneither side of the trailing edge of the battens back to small pulleys mounted on either side of the mast hoop and down to the mast base. Pull one set the sail forms one way pull the other set it forms the other way. Havent put so much thought into the top and bottom most battens but they would be heavier and probably solidly hinged so as not to detr act fron sail shape. topmost batten hoop would have a simple bearing to allow rotation supported by two halyards to keep the bearing flat.If required hoopes coul be also connected by ropes front and back inside the leading edge to remove some stress from the panels maybe reduce twist and as a fail safe to stop the lot coming down if a panel rips.
>
> Thoughts suggestions
>
> Cheers Tim
>