I recently treated myself to a new S1 pro 4.8 and While I was suitably astounded at the light weight I was a little concerned at the lack of reinforcing in the clew and tack area. This got me thinking as to why sailmakers are not looking at battens for reducing weight. The obvious answer is because they'll break. In wavesailing conditions this is true and who wants to be replacing battens all the time and probably repairing expensive sails as well. Just make them bullet proof and forget about it.
The thing is, I mostly use my wave sails for bump and jump stuff on the lake and I maybe wavesail twice a year if I'm lucky, and that would be in small surf only. So I started thinking maybe I could get away with some lighter battens in my manics. The manics are a good sail and very well built but not the lightest sails around. I jumped onto carbon fibre Australia and checked out some carbon fibre tubes and the cost came in at about 70 bucks. For that price I was willing to give it a go.
The battens in my manic 5.7 are 8mm solid fibreglass and I wanted the carbon tubes to be as close as possible to the old ones in stiffness. So being wary of giving my manic the race sail treatment, I opted for 7mm carbon tubes in the back section and 5mm tubes in the front. I made the join slightly forward of where the taper began on the old battens. To reinforce the join, I bound the join with sailmakers whipping twine with epoxy glue over the top. I've had a lot of grief with tube battens breaking at the join in my race sails and I've found this technique to be easy and very effective. None of the battens I've given this treatment have broken as yet.
The results, a half kilo weight reduction. The old battens come in at about 700 grams, the carbon tubes came in at about 200 grams.
Sail performance, the differences were slight but noticeable. most importantly, it still feels like a wave sail. Nice and neutral when you let it off. That part was non negotiable and any loss of neutrality would have been failure. The other differences were the shape stability felt slightly better, so slight it's tough to call. The centre of effort felt slightly lower although I may be confusing this with the centre of gravity of the sail. Biggest and best difference, a noticeable reduction in yawing movement in the upper half of the sail. Basically the sail feels a bit smoother and wants to go forwards.
From a bump and jump perspective, I'm calling it a success as the sail definitely feels lighter and handles nicely. I would feel ok using these battens in the small surf I muck around in but in breaking conditions the old battens definitely go back in.