A gennaker is built from coloured nylon. Cloth weight determines where it will fly well; panel colour changes its appearance without adding a separate coating.
Cloth weight follows the role
Lighter nylon fills in less wind and has a lower working ceiling. Heavier nylon remains stable in more pressure but will not fly as readily in a lull.
The selected Cloth therefore has to agree with the A-role, sail area, target wind range and handling system. A top-down sail also needs low bulk so the completed roll remains even.
See Downwind Sailcloth for the nylon families and their trade-offs.
Colour is the cloth
Use Base Color and Panel Colors to arrange the available nylon across the sail. The production panel layout is determined by structure and shape first; the colour scheme is fitted to it.
Horizontal bands are easy to read at a distance. Radial and vertical schemes can follow the structural layout, but need to be checked against the final panel plan.
Design for a curved, backlit sail
A gennaker is normally seen against the sky with light passing through it. Light colours glow, dark colours become more opaque and two similar shades may merge. Clear contrast and a small number of colours usually produce the strongest result.
The sail is doubly curved, so straight divisions on a flat preview bend when it flies. The final scheme is checked in an artwork proof.
V Stripes
V Stripes are contrasting chevrons that make twist and rotation easier to read from the cockpit as well as giving the sail a strong graphic structure. Their colour is selected in the configurator; exact width and placement follow the finished sail.
Logos, sail numbers, custom graphics and multi-color panel nesting are detailed in the Sail Graphics, Logos & Markings Guide.