Hello,
Long time cat sailor and windsurfer, I'm in the process to by a Mini land yacht (www.plumekart.com). It comes with a good 4.7 sail, but at 63 kg, I will need a smaller one: 2.5 to 3m2 one. As the sailing club has a good professional sewing machine, and as those sails are quite small, I would be happy to make my own sails... if I could find some templates not to start from scratch.
Would such templates be available in the land yacht community for small land yacht sails?
I saw that recutting windsurf sails is a option, But I don't have around small enough sails to reach 3m2 once recut... I also saw that going to a professional sailmaker, I have to expect something in the 400 to 700? for a 3m2 sail. Glups.
Best regards,
JMF
OK, seems that such template is not available...
Browsing in old stuff pile at the sailing club, I found a very old 3.2m2 windsurfsail. Good candidate for recut. But I do not see anymore the "earlier" threads explaining how to do it (was in 2018 I believe). I just see my thread and nothing below.
Is there a Seabreeze option to see older threads ?
JMF
try this....
www.seabreeze.com.au/forums/Land-Yacht-Sailing/Sail-making?page=2
FYI I was looking for old construction pages and was advised to search for 'page 2' to find old threads....it seems this trick also works for the sail making threads! This is great because I'm about to start my first yacht build and will probably need these older sail threads too.
This following link will take you to the construction plans foer the mini and has details on how to cut sails.
I'm going to try uncut windsurfer sails first with a 90 degree mast tube and if that fails I'll be looking changing the mast tube angle and cutting sails.
www.seabreeze.com.au/forums/Land-Yacht-Sailing/Construction/Lake-Lefroy-Mini-Plans--?page=1
Hope this helps!
Thanks for the tip for page 2 => hopefully works fine.
I have found a source for a 3m2 sail. I have also found an old 3.2 windsurfing sail that I will try to recut as an experiment.
I still believe that having similar patterns/ luff curves to the ones provided in the LLM thread for smaller sizes would help the DIY guys for those. If I find some time to have a look with sailcut open source application to design something, I will share it.
www.sailcut.com/handbook/en/#idm46129177594992
This tool needs the definition of the sails dimensions: this I can do from pictures here and there. Then the sail "mould" has to be defined and I don't have the orders of magnitude there for land yacht small sails (max depth in %, location of max, sail twist):
The depth and the shape of the sail can be entered at three levels located at the bottom (foot) the middle (sail's maximum depth height can be adjusted) and at the top of the sail.
The position of the point of maximum depth of a profile is shown under the depth value. This position which depend of the luff and leech shape factors is expressed in relation to the cord of the profile. For exemple: 0.34 means that the point of maximum depth is at 34% of the local cord counting from the luff end of the profile.
The luff shape and the leech shape can be adjusted for the Top profile and Middle profile only. The foot profile is always an arc of circle.
Under the luff shape factor, the corresponding value of the angle of entry of the profile is provided in degree. The angle under the leech shape factor is the exit angle of the profile. These angles are refered to the local cord and if you want to know for exemple the real entry angle of a profile with respect to the axis of the boat you have to add to the entry angle the twist at the level of the profile plus the sheeting angle.
The vertical position of the sail's maximum depth profile is controled by the vertical slide bar to the right of the left vertical frame.
In order to avoid that the leech makes a hook in the upper part of the sail when the wind increases, it is recommended that the Top profile luff shape value be higher than that of the middle profile and that the leech shape value at the top be lower than the middle value.
