Vic, you already know that sails are not sewn in the manner which Sergal has shown in the instructions. If I were you, I would take the time to check the sizes of the sails, and trim them to size if they are too large. If they are too small, you need make a new sail. Let's say that you find the size of the sails to be satisfactory, and that the clews are not wider than the lengths of the yards. Now is where you take crappy kit sails and make them better. You have two choices. You can cut off the edges, replace them with your own bolt ropes made from line, or live with the edges as they are, and take the loose ends at the corners, and use a needle to weave the end back into the corner or edge of the sail to form a loop. Cringles will have to be added at the sides of the sail by hand. The edges make for ugly simulations of bolt rope, but at viewing distance of 5', they work. Use PVA glue to secure the ends of the loops and cringles, and you will find this to be strong enough.
Personally, I bought a set of premade sails for
La Couronne, and they had the same zig-zag stitch on the edges that yours have. I still have the sail set if anyone wants then, but they were not good enough in my opinion. There are no kit sails that are even close to realistic, which was disappointing, but it forced me to make my own sails, and I was very pleased with the results. If you look at my build log, you will see that for my small scale model, sewing the bolt ropes would have been too large, so actually PVA gluing the bolt ropes to the cloth edges was the technique that was chosen. You have to apply a tiny line of glue with a toothpick, but it holds. I saw that technique in a YouTube video from Russia somewhere. Those Russians always seem to have incredibly high talent for scratch build ship modelling!
Whatever you change will be an improvement. Sail making takes lots of patience, but remember that crappy sails destroy the appearance of a model more readily than a crappy hull.
Model with crappy kit sails.
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Scratch made sail with sewn, and CA glue hardened edges, before bolt rope is attached.
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Kit sail versus scratch made sail with glued on bolt rope.
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