sailcloth for mainsail

Would just like to comment a bit about the Laser 28 mainsail discussion. If the sail's main purpose is to be racing, or if that is important to you, I would steer anyone away from just choosing a great cloth and a name sailmaker for the job. Been there and done that myself. Mistake.

There were not many Laser 28's make. The mast on these boats is very unique and that seriously affects the entire rig. The mast is extremely light and flexible. This has the effect that one must rely on tension in the upper shrouds to achieve good headstay tension. The backstay will not do much for this as the rig just bends more in the upper third. By the time you get sufficient tension in the uppers to stiffen the headstay, the rig looks like a banana with a huge amount of pre-bend. Sure one can tighten the lowers to keep it a little straighter, but the reality is that the rig sets into a significant amount of re-bend. Most sailmakers will to make allowances for this, mostly because they don't know of it. They assume most masts are relatively straight and fix their luff curve to suit. That allows the owner to make minor adjustments to his mast to make the sail slightly fuller or flatter using the backstay, etc. This will not do it with the Laser. The luff curve in the main must be nearly double what it would be on most masts. If this is not done, when you set the main to the mast, the pre-bend will pull all the draft out of the main leaving one with a very flat sail.

I wish to make my point strongly in regards to the Laser 28 mainsail. On this boat, the main sail is the "main" sail. If it is not right, the boat has no chance of achieving near its potential. I have no favourites among sailmakers. Voila has all sorts of stuff on her, but they have been cut and re-cut to make them work. I sail on two other Lasers who have Evolution mains designed by Bill Layten, and they are shaped and tuned perfectly for the boat. He has been working on that design for 30+ years on the same boat. You can send him your loose gauge and he can calibrate the exact tensions you require on your shrouds to make the mainsail set right and perform straight out of the blocks. You will likely go through half the life of another sail before you get it tuned right, if you are good at tuning, which likely you are not.

For a spinnaker (free flying sail) it does not matter. They have nothing to do with the rig. I have my own ideas regarding the genoa and its use, so I will not be getting a class sail for that purpose. However for the mainsail, and the lapper, both principal sails for this boat, I strongly recommend someone with extensive experience in making those sails for this particular boat.

I'm curious about the best mainsail cloth for the money and performance. I'll hopefully be replacing mine within the next year. I plan to use the blown out Dacron for cruising so I'm looking to get a racing main. 

The class rules specify a sail cloth weight. I went with a lighter dacron, because I did not get a dacron crosscut sail. I chose the dacron used in radial cut sails. The strength of the cloth is in the fill, not the warp, so the cloth does not stretch nearly as much. I love the sail! It is noticeably lighter than a crosscut sail, low stretch, great shape, and VERY inexpensive.

Hi Jez,

thank you for your answer. You are right, there is no need for dacron class sail in Germany. So for racing I use a set UK tape drive sails. Now I bought a new a new dacron main for touring. It comes from Quantum. When I studied the sailcloth specifications (Challenge Sailcloth 5.93 High Modulus) I found the information that 5.93 is for use in mainsails on boats up to 25 feet. For this reason I asked the sailmaker if the sailcloth is really strong enough for a 28 feet boat. He answered that the sailcloth for sure is strong enough because the boat is not that heavy and the the sail will be very well manufactured.
For me that answer was not a 100% satisfying. So I tried to find out what kind of sailcloth is typically used for class sails.

Best regards
Klaus


By the way: Beginning of April I will spent a couple of days very close to Lymington. As far as I remember Weymouth is almost around the corner. Will I already have a chance to see “Farr Out” on the water?

Hi!

Does anybody know which sailcloth quality (weight etc.) is 'normally' used for mainsails?

Klaus, Kiel, Germany