Desperate to sail 2015

Okay, Skyak, I tried modeling the lateen sail. Remember that I'm making it out of old gaff, so I'm very limited in what size and shape can be done.



I tried many different arrangements, and if I cut the mast in half, I can only make mast and boom, but not the yard. Yard would have to be about 400cm in length. So if I go with this, I have to find another very long tree to cut down (my conscience still hurts for the last one I had to fall).
This sail has about 5.1m^2 area, with CE about 2m above waterline.

I have absolutely no experience with lateens, so please tell me if such design makes sense - and if it's better than my proposed lug:



It has area of 4.55m^2, with CE about 175cm above waterline. With this design, I could use the top of the mast as the yard - then I only have to find something for a boom - about 230cm in length. Hard to find, but easier than 400cm.

What do you think, Skyak?

 

Well the lanteen sail is what I would want for extremely variable winds but the sail area is limited. You will want to keep the triangle pretty close to equilateral and not overhang the hull much. The most common lanteen rig is on the sunfish.

http://en.wikipedia.org/wiki/Sunfish_(sailboat)

As you can see it's a lot of area on a little surfboard of a hull -made manageable by low drag.

If you cut 3m off the top of your mast and used it for the yard and found a 3m branch to use as the boom (doesn't need to be straight) I think that makes about a 4m^2 triangle...which sounds small. So you would need to find sticks for the mast ~2M straight and the boom -4M to make a 7M^2. I think 5 to 7M^2 lanteen would be great.

Like Petro said you could go with a junk, similar to a lug but with full battens -but then you need many battens.

Or you could do your lug and swim occasionally.

I went looking for the sail cut guidelines for a lanteen sail and google's top image was a post of mine -see #37

http://www.boatdesign.net/forums/sailboats/rig-19-sailing-canoe-49626-3.html

 

Have you red my previous post with screenshots, Skyak? Just checking before I reply.

P.S. What about reefing with lateen? That would be very handy.

 

Maybe a sprit sail will work.

 

I'm in agreement with Sam-Sam. For simplicity, a peak sprit is hard to beat. It has the advantage of low CE and simple spars, short mast, only one adjustment (the snotter) and it can be reefed if a boom is used.

There are two kinds of sprit rigs. The peak sprit as shown in Sams' sketch, and the boom sprit which is not a boom at all. It needs no boom, it is adjusted with the snotter, it needs no outhaul, or boom vang. Not as easy to reef though it is possible. It can be scandalized in seconds however.

I sail my small flattie with some Sunfish guys. I have a Sunfish rig (lateen) about 80 square feet. I also have a sprit boom rig of 60 square feet. The rigs are interchangeable easily so I often alternate them. With the lateen I can stay with the Sunfish or just slightly ahead, maybe 10 boat lengths in a mile to windward. With the smaller sprit I can usually gain 30 boat lengths per mile.

 

Guys, you're not making this easy for me... My initial thought was dipping lug. Petros said dipping is not good, go with standing. I then asked if balanced wouldn't be better. While I was deep into research on the matter, Skyak said that I should go with lateen instead. I remodeled everything to check if that's possible. And then SamSam and with messabout say - you need sprit

All the other work has been done, at least to a point where I can't do anything else until I go on water and see what's lacking. Tomorrow (that is in about 10 hours in my timezone), I have to start working on the sail or the spars (cutting mast if needed, finding timber for yards, boom or whatever).

I need to decide, now. Sprit sail is good, I trust, but it needs lashing to the mast. I had horrible experience last year of not being able to lower the sail due to it getting stuck. That kind of scares me... It would need longer spar than lug, also...

I thank you for your advice, SamSam and messabout, but at the moment, it all adds to a lot of confusion. It seems to me that either standing (or balanced) lug or lateen is what I should do. I'll try sprit next time...

 

I had not seen your reply when I posted.

Looking at the sunfish the mast attaches to the top yard 1/3 from the top. Your design looks like it's below the half which would tend to twist off I think. If you make an equilateral triangle you get more area/spar length.

There are lots of videos on youtube showing sunfish setup.

https://www.youtube.com/watch?v=2AwrTrg-kN8

You can reef a lanteen -the yard tilts down. But the good thing about the lanteen is you don't need to reef because it can just point into strong wind with very little force. For the occasional gust it's much better.

I don't know much about gunter rig. I saw a guy sailing one that seemed happy and I read an article in wooden boat magazine where the guy spent a whole page saying how they are awful and one nearly killed him while trying to reef in a sudden storm.

Your lug looks like it fits the wood you have. Are you a strong swimmer?

here is an example of a well designed lug sail.

http://www.andrewlinn.com/plans/120301_michalaklug/index.htm

 

I thought it might twist. But that's the only setup I can do with the wood and sail that I have. I'd really like to make it equilateral, but then cutting off the mast top won't give me spar long enough, and the sail from which I would make lateen would only allow around 4.5m^2 sail.

So I guess I'll have to stick with lugger... I will try to replicate scaled down sail from the one in your link. There's a lot of useful information. Thanks!

I'd really like to make lateen like you suggested, but it seems impossible with what I have, or I need to make really small sail, and get another very long spar... Tomorrow I will take a look around to see if there is anything that long. If yes, then I'm doing lateen. If not - then lug.

In case I'll go with lug, I have to decide between standing and balancing. Skyak, could you advise on this? Which would suit my wind conditions here better?

 

I scaled down that sail, Skyak, but left the dimensions exactly the same. It seems that the largest sail I can do of this shape is around 4.2m^2, CE is 175cm above waterline, and mast divides into mast and yard with some to spare.

Here's how it looks:

http://www.boatdesign.net/forums/attachment.php?attachmentid=93358&stc=1&d=1407113337

Is it better than my previous lug proposal (it had slightly more area, same height above waterline)?

 

That design is for a balanced lug and appears to be well sorted. The boat page is here.

http://www.duckworksbbs.com/plans/jim/laguna/index.htm

I don't have a preference other than it be a tried and tested design made from flat cut material like you will be using. The balanced lug takes less sheet force -you haven't mentioned having any pulleys.

Good luck with the stick search.

 

Okay, I'll go with balanced. I believe my lug design has higher aspect ratio as well as sail area. However, this design you provided requires lower mast, and you say it's proven.
I made a mistake earlier. With the design you provided, maximum I can make is 3.9m^2, and with my lug design it's 4.5m^2. Significant difference...

Here are specs again:

My lug design:
Sail area 4.55m^2
Mast height 285cm
Yard length 195cm
Boom length 225cm

Screenshot:



Laguna lug design (the one you provided):
Sail area 3.97m^2
Mast height 192cm
Yard length 288cm
Boom length 245cm

Screenshot:



Both designs will require me to find something for the boom, but that's all. CE distance above waterline is pretty much the same - 175cm.

I need to decide, and with my lack of experience, I find that difficult...

Skyak - or someone else - can you help me choose between these two?

 

Hi Laukejas.

When I designed the rack, I thought you had plenty of lumber. Now that it

is clear that you don’t, it is also clear that the few planks you have
left should be turned into either a rudder or a ‘Board.

What I presently have in mind is a single, side mounted dagger board.

Making two Lee Boards is just a waste of material, as that which is above the waterline contributes nothing to lateral resistance. This is fine, if there is plenty of wood. If there is not, a more efficient use of what is available is called for.

Sailing in variable winds, which is the lot of small lake sailors, does
not work well with Lee Boards, which can float up, the first moment the
boat is becalmed. It can drive you mad. I know this from experience, as my first boat had them. I ended up making a rack on each side of this

boat to keep both of them down at the same time, before I got the boat to successfully sail.

So I designed a crude Dagger Board case for you (see attachment).

It is not made out of your precious remaining lumber. It is made of what I call “harvested wood”. This wood can be gotten from fallen branches which you can probably find in the woods. The thickness I call for are what I think is minimum. You can go thicker.

The idea is to square off the ends of each piece, so the joining piece
can lay flat against it, kind of like with a log cabin.

This structure can be attached to the hull with two lines.

One (4) goes over the gunwale and can attach to the inside side of the
side deck with a hook.

The other (5.) goes under the hull and up the other side. It can also
attach to the inside side of the other side deck with another hook. Or
it can be brought over the other side to join the top line, as in my
illustration.

This will allow the Dagger board to retractable, yet keep it more or less
in place when down.

I agree that a Lateen sail might be better than a Balanced lug, for the sailing conditions you are expecting. However the Tyvek you have available may not allow you to build a big enough sail.

For this reason, I recommend you go with with the balanced lug. The first one yo drew will probably work the best, despite its long, unsupported luff.

I would cut the sail absolutely flat, with straight lines along the edges.

The reason for this is that the Tyvek stretches. When the sail is set for maximum drive, the material will stretch to make a passable airfoil. When its feathered into the wind, it will flatten some and perhaps flog a little less.

A spritsail with the same profile shape might be even better, because all the sail is behind the mast, and the diagonal sprit is less likely to spoil performance on the bad tack as the sail in front of the mast.

 

Yeah, Sharpii2, I thought I had more lumber. But when I completed the mast step, I realized there isn't that much left fore some odd reason. Maybe I miscalculated...

But if I'm NOT making another daggerboard, then I have 3 additional 9.5x1.8x100cm planks, which I can combine together for thickness, and so on.

I like your box idea, thank you for taking time to sketch it. But if you remember, this boat has extended rail surfaces (visible in photos I posted earlier). So the structure you described should go under the rails, yes? Rails are about 4-5cm wide. If I took lumber large enough for horizontal beams, daggerboard box slot should still be protruding.

Since my daggerboard is 1.8cm thick, it would make sense to make the slot around 2cm, right?

IF I made spritsail, I'd need to make some kind of sliding throat for gaff yard, yes?

P.S. I modeled the same sail, just as a spritsail:



I'm not sure if yard throat should be lower, but then it requires longer spar, and the mast from which I'll cut it limits it...

P.S. Or I could make sail not so tall, losing some area, but then I could do better sprit angle. Not sure if that's important.

 

Okay, so after scouring the forest for about an hour, I found the perfect tree: clearly fallen in a week's time, a 330cm (usable length) straight pine with 6cm diameter at bottom and 3cm on top. So my options have vastly increased, and now I such spritsail:

Mast height 263cm
Yard length 300cm
Boom length 217cm

Sail area 4.5m^2

Screenshot:




I'll try to see if I can make it larger. How does this look?

 

Hey just noticed this thread, I love this kind of stuff! I made a makeshift sprit rig for my little square boat appie, using a 4 by 6 tarp. There's a little video here: https://www.youtube.com/watch?v=KLkqoM7jvE0

The mast partner later broke and I added some stays to keep the mast upright. I've also used the same tarp as a dipping lug. Sprit was simpler to manage and sailed better. Keep it boomless and have a brailing line in case needed.

I think in your case I would have gone with a wooden brace from inside the bow to the bottom of the hull in front of the seat, with a hole or something as mast step. Some stays to bow and oarlock things. Hang the leeboard off the oarlock socket as well. Just a simple piece of string. Move it across on every tack.

Don't overthink the rig just make something and go sailing. Changing between the different lugs is a matter of a few minutes retying. Sprit just as simple, just need a longer skinny stick. The sprit can be surprisingly light stuff.

Here's another video where we botched a 10sq m sail to my outrigger canoe. Very entertaining and a bit cold and wet. https://www.youtube.com/watch?v=kj3vP_kM5tU