Welcome to the forum Jay
To answer your question a land yacht sail is tensioned differently to a windsurfer
so to adapt one for landyachting some of the curve needs to be taken out of the luff
In the construction section of the forum there is an article on altering windsurf sails this way The third article from the top I think
That was the starting point for me when I did my sail and it turned out fine
Welcome again and good sailing!

Welcome Jay. I'll leave your question to the many experts we have on here, but just wanted to say welcome and post some pics of your work in progress. You'll be doing the first kite buggy - landyacht conversion that I've heard of.

Gidday Jay.......welcome to you and your family , happy sailing...walkaboutjoe

j murray said...

Gidday Jay.......welcome to you and your family , happy sailing...walkaboutjoe

Thanks walkaboutjoe,
I'm looking forward to starting to land sail. kite buggying is starting to get hard work. I love using a kite, and it adds an added part to the experience in controlling the kite and altering its power effect while on the move, but from what I have seen sailing is a whole new ball game.
regards
Jay

Jay, i will try and explain the interaction between the mast and sail on a landyacht.
A landyacht possibly is the only thing that uses a sail from light winds to VERY strong apparent winds in a very short time.
Basicly a sail is a "wing" on edge and the yacht is actually sucked along with the lower pressure from the "back" of the sail. The deeper the draft or depth of sail curve the more pulling power the sail will have BUT less speed, where as a flater sail will have more speed but less pulling power.
Just think the difference between a tractor and a F1 race car.
With a combination of sail / mast working correctly when the mast is straight the sail with a curved front (luff) will induce a lot of draft in the sail, and when sheeted on the mast will bend and reduce the draft and then finally fully sheeted in will give you a flat sail, a bit like an automatic transmission in a car.
Using a sailboard boom sort of locks the sail shape to a fixed draft and limits the overall speed, just like a car stuck in 2nd gear.
I hope this explains it.....

If its any help Jay I modified my Windsurf sail using a domestic Janome sewing machine [or at least my wife did she wont let me near her machine]
All the sewing needed is done on the edges of the sail so the small throat of the domestic machine can cope with that part
double sided tape holds everything quite well while the sewing is done
The heavier corners were a bit of a challenge but it can be done with perserverance or as a last resort a canvas company could do that small part
[I hand sewed a tiny bit where it was really tough]

HI,
Well here
is a shot of progress so far, but I fear the sail is the wrong shape for what I need. Still it will do for now to get going
regards
Jay

Hiko said...

Think you may be right about the sail the centre of effort looks quite far back
[looking from this side of the globe !]
You have a good start point though Give it a shot!
Will be interesting to see how it goes Good stuff let us know the results
We can all learn something from each other

Yes, from my very limited knowledge I recon the mast needs to move forwards 50-60cm minimum. I have worked out a way to cut and re weld without any difficulty at the front. Not having any length on the buggy makes setting up difficult at the moment The sail is big but it also has a low aspect ratio, so the boom is very long. My Father-in-law has had this sail ages, it must be 20 years old. As it is my only sail at the moment, and I did recut the luff it will have to do! one thing for sure is it will move OK just not to fast. I will be making a land yacht from scratch, so all I learn off this one will pay me back I hope.
One question I have is having the C/E so far back will do what to it? I'm guessing it will break away a lot on sand?
Thanks
Jay

cisco said...

responderman said...
One question I have is having the C/E so far back will do what to it? I'm guessing it will break away a lot on sand?
Thanks
Jay

It might make it a really good stunt yacht for doing 360s.

LOL, didn't know such a thing existed, sounds like kite buggies again.

Thanks landyacht, I just followed the instructions on the construction page, and the rest was down to luck.
I think I am using the wrong part now to talk about construction. So I will stop using this Hello post and start another one in construction page when needed.
Thank you all for your help
Jay