BYYB Forums

It's time to replace Ginny Rae's sails again. I bought a large genoa on Ebay, and plan to cut a mail sail and jib from it soon. I ordered the dacron tape, and thread from Sailrite. Hopefully I can start measuring twice or three times and start cutting them by months end.

Greg

What weight fabric is the genoa Greg?

Greg, my only advice is put a thimble on all the fingers of your receiving hand not just the index one.  I am currently finishing sewing on a poly tarp sail.  I used the wifes machine for the long runs but the small support areas are being sewed by hand.  When I make a new one in a few years, (hopfully I'll get a few years from the poly?), I thought I would be brave and try a different material.  A lady at a fabric place here suggested I use flag satin.  It is the material that is used in making flags.  It's stronger and a little stiffer then ripstock and more UV resistent.  I think most of use have seen a flag in our time so what think ye all about that type of material?  There is always the stuff from Sailrite or Duckworks but thought I'd ask.

Paul I believe the weight is 5 oz, it's certainly heavier material than my white tarp sail. Terry I have a sewing palm that has served me well for many years, the thimbles on all fingers is good idea too. I've always thought than flag material seemed kind of light for sailmaking, just my opinion.

Greg

The material they make cheap flags out of is nylon, which is fine for light air down wind sails, such as a spinnaker, blooper or staysail. This material is very stretchy so it usually has to be sewn into fairly narrow panels with seams oriented along stress lines.

Rip stop nylon is slightly better then regular nylon, but again it requires careful construction to keep it's shape.

Slightly better flags are made from flag satin, which is a polyester (100%) not satin, though often called satin polyester. In a fabric store it would be something like "Contessa satin" or "costume satin". It is slightly stronger then nylon, but still very stretchy and likely not available in weights useful for sail making. The real big problem with these types of fabrics is the weave used, which is what we call a warp dominate weave. It makes the material very weak in one direction (usually weft) and unsuitable.

Really good flags are made from cotton.

Tyvek is another material that has been used. Most use the stuff they can get at the big box store, which has a Tyvek logo ever few feet (comes off with solvent), but more importantly it's got holes in it. Yep, little tiny holes, designed to let moisture out of the wooden structure it's wrapped around (it's called House Wrap). There are three types of Tyvek (last time I checked) and the other two are not perforated. This material is less stretchy then nylon. It makes a horrible racket when used as a sail. The noise is enough to make you not want to use it.

Poly tarp is currently about the best of the cheap materials, but there's good and bad poly trap. Cheap poly tarp will have a low thread count (weave) and low denier (fabric density). A common tarp will have 10x10 weave and a 800 to 1,000 denier. A good tarp will have a 12x12 weave and a 1,200 denier. The stuff I've been getting is a 14x14 weave and 1,600 denier, which is a little heavy for light air use, but is less likely to blow out in the winds I usually go out in (I can be a bit crazy a times).

Greg, be careful how you cut up that stay sail. The camber, twist and washout will be different then your needs for a mainsail. When you get a scrape piece, cut it into a 36" square, fold it neatly and weigh it on a postal (or crackhead) scale.

Well Saturday is the day that I have the time, and nerve to tackle the sail project. The lawn is clean and dry enough to spread the sail out today. It appears there'll be plenty of cloth to make a main, and jib. I've been looking at sailmaking videos on
youtube. I'll try to shape the sails as best I can. I'm doing the work in an indoor shop. I'll try to keep a photo journal of  the event.

Paul the sail's panel seams will run parallel to the gaff from the luff of the main sail, just wondering your thought on that? The angle between luff and foot is 75 degrees, close enough to the plans 78.

Greg

There are several potential problems cutting down a bigger, professionally made sail into a smaller one. The biggest is where do you place the draft of the sail and working around areas where there is "washout" or "tuck" in the old sail.

The old sail likely has a little washout at the top of the sail, particularly towards the end of the gaff, where twist will be worst. This will dramatically alter the draft of the sail if you butt your new sail outline against the gaff.

I've actually done this on a few occasions and the very first thing you need to do is mark the sail. Attach a come-along to the tack, now tie the head of the sail to a tree and attach the come-along to another tree and tension it until the luff is fairly straight. Being horizontal, it'll never be really straight, but the tension should give you an idea. Now, grab the clew and walk it out until the sail is hanging naturally and the belly is clearly viable. Use a post or stake to hold the clew in this location. This is exactly how a sail loft checks it's work BTW. If it's a gaff arrange a broom stick or other fairly light but stiff hunk of wood to hold the gaff out, but position it off the head so it'll pivot. Make the gaff end the same height off the ground as the clew.

The first thing you'll notice is some odd wrinkles. This is the washout and adjusting the gaff and clew will erase them. Now, looking at the sail from the foot, with your head close to the edge of the sail picture your new sail sitting inside this big old sail so the respective bellies are about the same. If the old sail has an attached foot, stay away from this area, unless your foot will be attached. Also avoid the washout area near the outboard end of the gaff and upper portions of the sail. The panels are cut flatter in this area, which will screw with your efforts. In general you want your new sail to kind of float in the middle of the old sail, probably more towards the luff more then the leach to keep the relative bellies in similar locations.

If you make your cuts this way, you'll have the panel seams, perpendicular to the leach and too much belly in the gaff and no tuck in the foot. You may wish to slide the sail a little into the washout area near the gaff, but don't get greedy, you can install a dart or a pinched seam later if there's too much belly for the sail to set right. Using the old luff, foot, head or leach will insure the draft of the sail is wrong and the sail will set poorly. It will save some hand work, but the results will be disappointing.

A few degrees will not matter in gaff or foot angle, though the lower foot on your boom may be inclined to bang heads more often. If you cut the sail the way I've described, you can have the exact angle you want.

Placing your new sail on the belly of the old as I describe above will cause you to to make a new luff, foot, gaff and leach seam. This is ideal as you can incorporate the round you need and avoid all the built in stuff on the old sail. Naturally you should also remove the old reef points, etc. as they are no longer valid. You'll have lots of patches and little stains from the previous stuff, but the new sail will fit and set, which is the bottom line.

Well the first cut jitters are a memory now. The wife's sewing machine is cooling down from it's first workout.

Saturday afternoon Denis and I tackled the dacron sail project, we used a large floor area at Denis' workplace. Our first step was to spread out the sail and take some measurements.



This was a very large sail, There was enough fabric to yield a main & jib sail, plus a possible second jib, and plenty of extra for corner reinforcing. I double side taped the cut ends, and used 2 inch folded dacron to trim the ends.



My less that perfect sewing skills got a good test, so far. The next step will be to reinforce the throat area of the main sail, and the clew area of the jib. I hope to complete the tasks some time this week, and test fit the sails next week. Watch for further updates.

Greg

Well I have a fine looking set of sails now. The Kenmore sewing machine survived the ordeal, and no broken needles. I reinforced the throat with 6 layers of sail cloth.


I calculated two sets of reef points, the first set at about 3.5 ft from the foot, should reduce the area by 42 SF. The second at about 5 ft, and additional 22SF. That amount of reef will suit me better with our lake that can get nasty at times. I plan to have Ryerson help me install a quick reef system on the first reef position.



I moved on to the jib, made the reinforcement of 6 in wide dacron tape. The seamstick tape works great for holding patches and trim for sewing.


My helper stayed on his task of holding the jib just fine.



Here is the finished clew prior to installing grommets.



Here is the finished sail set, hope to put them on the boat by this weekend.



I plan to initially set up the rig with a loose footed main, I'll do some water trials, and if I'm not happy I'll trim the sail, and set the grommets for using the traditional rig.  The water is soft, and my new sails are done, Yea!

Greg

Nice neat job Greg.  Happy to help with a jiffy reefing system, just say when.