Surfing & Windsurfing/Battens not staying put
I recently purchased a wave sail with 4 battens. It is used. I own several larger freeride sails that usually have more battens (some 7). On my other sails, when I rotate the battens to one side of the mast, the battens snap to the other side of the mast and the shape/curve of the sail stays fixed even if the sail is not powered up. On the new wave sail, when not powered, it flops back and forth when it is on one side but not the other. In other words, it needs the wind in the sail for it to keep the sail shape.
I played with downhaul and outhaul tension and batten tension. I set them to spec and then change each one way or the other. I can change the behavior, but not eliminate it.
Is this just something that happens with sails that have fewer battens or is there something wrong?
My wife, who is a beginner, is bothered by this. As soon as she loses the wind, the batten is popping back at her.
Wave sails are a bit different in how they react. They are designed to power on and off quickly as wave sailors use the wave power a lot and like to depower the sail when wave riding.
But, the sail should be staying fairly shaped and working similar to your freeride sails. From what your are explaining, I would recommend checking the sail specs for the type mast it is asking for. It sounds like your mast may be too stiff. Most wave sails like a 24-27 mcs stiffness mast. Most freeride sails use a 28-30 mcs. It also sounds like not enough downhaul. If the mast is too stiff and you are not downhauling enough, your situation will happen.
Another issue that could be a factor is the type of mast. Some wave sails, especially older ones, used 'flex-tip' masts vs. constant curve. Pretty much all sails now use constant curve but if by chance your wave sail is a flex-tip, then it won't work well on a constant curve mast. North sails made a lot of flex-tip sails but there were others too. Newer technology and sail shapes made flex-tip sails/masts obsolete.
Hope this helps.
Keep on sailing,