The living room is too narrow to accommodate the tarp fully unfolded. Luckily that part gets trimmed off and used for reinforcements and binding.
I have cut off the original edges with the factory grommets and binding. They are simply not strong enough. The edges of the tarp will be taped to the floor so there are no folds so I can mark accurately. The cats move everything around quite a lot and taping saves aggravation---mostly.
To locate the corners of the sail I trim one side cleanly and place a mark on one end to be my first good side and corner then measure exactly the right distance and place another mark for my second corner. Then I use a tape measure and draw large arcs from the reference corners. Where the 2 arcs intersect I mark with my dry erasable marker.
I have calculated the length of all the sides and the diagonals so all I have to do is transfer these measurements to the tarp. If there is enough material I make a wider seam so I can just fold it over a couple of times, otherwise I cut a binding strip from the extra material. I cut the strip on the same angle as the sail so it will stretch the same way.
Once all the marks were made I added the extra bulge at the foot and top of the sail to add some shape. I had to be really careful when I removed the tape. It stuck to the orange covering and tended to take it off. This tarp is supposed to have extra ultra-violet protection. I don't think it is very thick. Once I have a good idea of the kind of sail I want I will make it or have it made out of good stuff.
The polytarp gets cut carefully, following the lines I made. I would have been nice to just be able to roll the edge a couple of times and sew it down but the tarp was not large enough. At this point I cut out the corner reinforcements. They get cut with the fabric lined up in the same grain as the sail. I made at least 4 patches for each corner each slightly smaller. I stuck patches together with double edge tape I got from the dollar store. Saves some trouble and keeps things in place until I sew them.
I try to use tape where I am not going to sew because the tape gums up the sewing needle. I attach the patches on one corner then go sew them. I then proceed to the next corner.
Corner patches ready to be sewed down.
I turn down the edges and crease it with my fingernail. Then I sew each patch on the sail. I use a zig zag stich that consists of 3 straight stitches per zig. I also sewed reinforcements where my sail gets tied for reducing the area. Corners were rounded and over-stiched.
All the patches have been sewn securely on. The edges have either been turned under and sewn or else bound with a strip of polytarp. I have added little patches where the grommets are planned. The tarp by itself is a too thin for the grommets to bite in and hold. The extra thickness of the little patches works really well.
I used a soldering iron to melt holes for the grommets. It has the advantage or melting the edges together and there is no unravelling. It is also very fast.
These patches and band reinforce the area where I can reduce the sail if there is too much wind. As soon as the hole is melted I insert the grommet and the tarp material hardens and shrinks around the grommet. I did each side of the sail then went to the front steps and inserted the back washer and bashed the grommet in. The front steps are concrete and work very well.
At this point the sail is complete. I checked it for any obvious mistakes and cut any loose threads. I had forgotten to put a back washer on one of the grommets so I had to cut it out, repair the hole and regrommet it.
Tired after a long days work! My assistants take a well deserved nap
After tying a piece of wood to the boom to make it long enough I attached the new polysail and went out. The sail edge luffs slightly in gusts and I will need to either stretch this better with the snotter, or maybe modify the shape or rope the edge. To be determined...
Sail sets not too badly in low wind. It is also quite nice to handle and doesn't twist as much as the white sail. I'm not experienced enough to understand why. If you know send me an email.
Here is the sail after some fiddling in the riggings. You can see the piece of wood I added to the boom to make it longer. I also added a small block to tighten the snotter more easily, not so much friction when I pull on the line. This sail points higher and has a wider foot, but the mast side is not as long as the original one. This is all in aid of trying to balance the sail. I think this is a great success and the sail works quite well.
Year 1: This sail has now been out about 20 times. So far it is the most successful sail I have tried.
It doesn't points as well as I had hoped although it is better than either of the 2 other sails. It started out pointing better but luffing on the edge. I hollowed out the edge but lost some pointing ability.
I made a new boom that fitted the sail and took off the little extra piece of wood I had added to the old boom. This helped me lace the sail better and get it looking nice and tidy before going out. I simplified the lacing and tidied up the snotter attachment where I added a little block to make it easier to adjust. I'm hoping to send the snotter to the back where I can tighten or loosen it from where I sit behind the middle seat.
The new sail is much better than the previous ones in low wind. It is about 6-7 feet larger than the nylon sail and this means that it moves better in very low wind conditions. In fact my little Skerry was smoking the big boats in low wind!! Go Cricket!
As the wind increased my little boat behaved very well and moved well. The new sail was better on every points of sail. In gusts it lifts and depowers safely. It has much less twist than the other 2 sails.
As the wind increases the outer 6 inches were luffing quite a lot, so I took the sail off, cut a hollow in the outside edge of about 3 inches at the most, and sewed in a rope inside the seam. These 2 things fixed the luffing and improved the performance except the pointing, this was reduced. This sail has some shaping. There is a slight bulge top and bottom and a hollow on the outside edge. I can see that the sail takes on an airfoil shape much better than the other 2. My little boat now moves well and compares very well to bigger boats on some points particularly with the wind behind me. I'm faster than many longer hulls with much more sail.
I'm finding that it is making the mast/sprit/boom bend more than the other 2 sails and I don't think that I can increase the size of the sail anymore without stronger spars and mast.
I tried to take it out in high wind and it was simply too unmanageable for me. I de-masted and rowed!
When there is a lot of wind this boat has some trouble tacking because it is so light. The wind is more powerful than the speed/inertia. I have to gybe. With 2 people it is better.
This orange sail is the best one so far. It is a good size, points much better, is comfortable and safe. It brings the boat to hull speed and is easy to control. At this point I will experiment with bringing controls to the back where I sit.
I wonder how a Chinese junk rig would work? ...
I made a new sail based on the orange polytarp sail and it is very nice. I cut down and modified a kit I had bought from Sailrite for a balanced lug. In the end I did not like the lug. I also added a jib and this improves it even more.
Links to the [hull part 1] [hull part 2] [birdsmouth mast] [rudder and centreboard] [sails] [oars] [cleats] [daggerboard well and mast step] [it floats!] [I'm sailing now!]
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