What is considered to be the best way to remove the curl in straight from the roll sail material ?
In my limited experience I have only used .0015 inch florists wrapping foil and lately some .002 inch drafting film but they both exhibit curl.
I have tried using battens but I suspect they are really to give shape to the trailing edge ( oops, I must remember to use the correct terms - Leech ) although I suppose they are both concerned with stiffness in one form or another.
Cheers,
firstfooty