Guess that I am entering some of the most nebulous area of this build and so I will be asking some simplistic questions. I got some ripstop nylon at Joanne’s the other day; a lot, they had a five yard minimum:headache: . At least it was not costly. And I can make a lot of mistakes!
OK, using this material, how much should I allow for hems and should I put anything in them to stiffen them? Can I use the same material for corner reinforcements? Would it be best to double hem the foot and the leech? Should I glue or tape? And, last, battens?
Ah! bear with me guys
Bob
Hi Bob,
I haven’t used nylon, but here’s a couple of general ideas that might help:
First, you want your sails to be as light as possible. If the fabric you got is heavy, find another use for it. I’ve used the stuff that florists wrap flowers in, and drafting mylar is another good choice. Other good choices are available from model yachting suppliers like GBMY. I’m not saying nylon won’t work, but it’s gotta be thin and light.
Second, try cutting your nylon with a soldering iron that has a blade, or heat-sealing the edges in some other way. I would not recommend sewing any of the edges, especially the leech. Corners can be reinforced with a second layer and sewn. The idea is to not stiffen the sail at the leech or foot…so that it easily takes shape in the lightest wind.
Holes for mast loops and sheets can be made with a heated needle. The melting of the fabric should make a strong enough “eye.”
Battens probably won’t be needed unless your sail has an unusually large roach. If needed, try thin plastic from packaging. You don’t want anything too stiff or it will flatten your sail and hurt more than help.
Single panel sails work OK, so you don’t need to go to the trouble of multiple panels unless maybe you get into serious racing.
I suggest using Brett’s sail plan for Bobabout as a good starting point for your design. It’s tried and true.
Keep up the good work…and show us more pictures!!
Bill
Remember to rotate the sailcloth so that the strong thread (the warp… the long side of the cloth) are in line with the leach. Otherwise the leach which carries the highest load will stretch and ruin the sail.
Thanks Bill!
You took the intimidation right out of me. Right after I read your post, I pulled the tip out of my soldering iron and turned it around. Cut a slot in it and tapped for a screw. Made a blade out of 1/4 x .015 brass and it works like a champ!
Yes, I’m not smart enough to design my own sails and I am using Brett’s rig. I drew the sails up full size in my Cad program (DeltaCad) and printed them out. Each sail printed on two sheets and I put them together with tape on a light table. I, then, taped them to the nylon and cut the sails out with the tool. Worked GREAT!
BTW, I did pick the lightest material they had and it is very thin. Wasn’t my first choice in color, but was the lightest.
Bob
OK, bear with me, here comes some more simplistic questions. I am building Brette’s rig for my boat and between looking at pictures of what others have built and what he has drawn I have it pretty well figured out.
Here are today’s questions. I see the pin in the forespar that is used to locate to a hole in the deck, right? Keeps the whole turning? Now, the other pin (or is it string) that pivots the front of the jib attached to the forespar? I can’t seem to figure out how the jib sheet is run. Does just simply go to the servo horn? And do you just glue the knot where the vang and the main sheet are located on the main boom so that they don’t just slide?
Bob
A true novice!!!
Sounds like you’re doing fine, Bob…
As you thought, the locating pin is inserted into a hole or slot in the center of the deck to keep the rig from rotating.
The connection from the forespar to the jib boom should be a line or swivel. It needs to allow the jib to swing out easily in light air. Line seems to be fine on these little boats, but a small fishing-tackle swivel would probably work well, too. Just don’t use anything heavy.
The main and jib sheets can both be run directly to the winch arm. The winch arm will need to be longer than a standard servo horn to get enough sheet travel. If you want to be able to detach your rig easily for transport, run one sheet from the winch up through the aft corner of the deck and tie a loop in the on-deck end. Bring both main and jib sheets back and terninate them to a clip. Then you can clip the sheets to the loop for sailing, and easily unclip to remove the rig.
A touch of glue on the vang attachment would be OK, but you want to be able to move your sheet attachments on the booms, at least until you have everything where it works best. A few wraps around the boom and a tight knot should hold it pretty well.
Keep up the good work…Bill
Thanks for answering my questions, I sure do appreciate it. On another board, it was mentioned that he uses a double purchase system on the sheets. Can anybody explain this a little better? I am assuming that the line is not anchored to the sail arm in this instance? Here is a picture of my progress, I am having a lot fun! All the fittings are hand made and, do move very freely.
Bob
Here’s a basic drawing.
The end of the sheet inside the boat gets (1) anchored to something like a screw eye screwed into a small block (glued inside the hull). Then the sheet goes through a hole (2) in the end of the winch arm. You can use a pulley instead of a hole. Then it goes through the fairlead (3)in the deck and to the boom.
fwiw
After seeing a photo of a FOOTY with a LATEEN sail made by Rick on the FOOTY website the old brain started to work on a modern adeptation of this very ancient style of rig.(as ya do):mes:
I went scrounging to my good friend Brett Linton of Linton sails here in Wellington http://www.lintonsails.co.nz
who allowed me to snaffle some offcuts of the most colourful spinaker cloth you have ever seen.
A couple of days later I had the mark I version of a Lateen Swing Rig.:p:jap:
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There is still plenty to do in the way of development, so don`t hold your breath. I just thought I would post it here to whet your appetite and provoke some thought.:devil3:
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Heres what ive been working on for a while rig wise.
Ian,
What’s the purpose of those dual verticals?
Brett,
Wow, I really like that shape. It reminds me of what I was suggesting in the wingmast thread( http://www.rcsailing.net/forum1/showthread.php?t=1582&page=3 ), minus the shaping of the leading edge. I think I’ll try something like that with the hull I just bought from you. Do you mind?
Ian,
Great idea, let us know how it works. Old stern steering iceboats used to use an “A Frame” mast with lateen sails
Bill
ps to Tomo: The “dual verticals” are used to eliminate the “crease” in the lateen sail which occurs on one tack
No problem Bill,go for it!
I put the mast tube on these rigs about 4 inches back from the bow.
These rigs are really very nice,simple to build and perform well.
attached is a sketch,use the photo for reference as well.
Thanks to Brett agreeing to publish his design, I have used that as a base for my own version. (nice way of saying I copied it):mohawk:
All made from that new hi tech material called WOOD.
Easy to shape, can be glued, non toxic, flexiable, light, drillable, a very clever compound. Hats off to ever invented it.
Mast is tapered in the manner of the FINN masts of old.
Main boom Balsa core with ply sides, doubled at the forward end.
Crane laminated ply 3x1mm sheets,
Sail cut down from old EC12 experiment. Very lightweight.:diablo:
Next step is to do the pocket luff…hmmmmm?
Hey Ian,
I might just be speaking for myself, but your large pictures really tax my poor dialup connection!:weeping: Otherwise, that looks really super! How tall is your rig? Looks really simple to make.
Bob
Ian,
Absolutely beautiful!!! I think Brett is really onto something with this rig & I’m building one myself, but it’s not nearly as nice as yours. I liked the bend in yours. I’ll get a photo off when it’s looking better.
Bill
Yes, sorry Bob I had not thought about the size of my photos.
I have resized the most recent ones.
The mast is 450mm high as per Bretts drawing.:magnify:
It might look cool to have a curved luff but I may have shot myself in the foot as it is not an easy task to fit a pocket luff with such a curve.:ihat:
May try some heavier cloth also as I had a look at some windsurfer sails yesterday to get some ideas to help.:darth: Some clever people out there.
Getting closer to posting some timed runs as easter approaches.:crazy: