Originally Posted by chucklesR
It needs to be dacron, and the battens typically fiberglass. Sailrite.com | Home
is a good supplier of both, or Discount Marine and Boat Supplies - Inflatable Sales - Defender
. You can also probably buy what you need right here at sailnet.
That's the fact part, now the opinion. If your sail is that badly beaten putting in new batten pockets won't help because you really need to get it right- battens come in all shapes, strengths etc - and just guess won't get it right. You'll wind up with a baggy sail and poor shape. Battens have a lot of force on them, the idea of one shooting out the sail when you tack should be on your mind.
You are better off cleaning up the torn parts and going batten free. Or buying a new or newer sail in better condition (try searching for used sails online - several places sell them, for example Bacon Sails & Marine Supplies - Discount Sailing & Boating Supplies
Chuck gave good factual advice. You almost have to look at the batten pocket as an attachment, make it and then sew the pocket onto the sail. You will need to make allowances for the area when it reaches the mast. Best thing is to get a sail slide with a pocket the batten fits into. Sailrite has sopme excellent advice and will be able to give you the ideas to fabricate this yourself.
In terms of the sail you are doing, I agree with his advice also. If its a tired main, the battens will not help it. If it only used half its life though it may be worthwhile. I went from a partial batten main to four full battens with the new one I bought from Quantum 3 years ago. The sail shape difference is dramatic. Battens will increase the life of your sails and help older sails maintain the same sail shape as when the sail was newer. For the average sailor cruiser I would suggest at least a sail with 2 full and 2 partial battens or at least a number of partial battens.
As Chuck pointed out there are large loads on the ends of the battens so they need to be addressed when you construct the ends. The the batten at at the main we just talked about. Any well designed batten pocket will have a material cover over the end of it which will prevent the batten from ever shooting out. I have never had this problem with the battens we have because of this.
In terms of material, fiberglass is usually used with encaps to prevent sharp edges on them from ripping the sail material. You will need a leather palm protector when you sew, special needles, sp92 thread ( protects agains UV degradation.