Plan B sails are painstakingly crafted using precisely engineered templates to shape the luff curve allowances and calibrated blocks for the camber allowances of the conventional seams, that are glued with adhesive tape.
The sail forms have been developed from theory, trial and observation while sailing, using a masthead video camera.
I use translucent DuPont Mylar film in both 50 and 75 micron thicknesses. The B mainsails, C jibs and C mainsails are made from the heavier film.
The available alternative, smooth finish, transparent 50 micron DuPont Mylar film is preferred by some sailors, particularly for jibs, because tell-tales are readily visible from both sides of the sail. This untreated film may be more durable.
Jibs have pocket tape reinforced luffs with a wire forestay inserted.
Mainsails have pocket tape reinforced luffs with a wire jackstay inserted and are pierced for this wire to be attached to the mast with five loose ties, tied with a small ( 2-2.5 mm diameter ) spacer. Sail camber can be trimmed by adjusting the backstay to bend the masthead aft. The mainsail luff allowance is cut to suit a straight mast and will accept only little aft mast bend to flatten the head of the sail.
All reinforcing patches are white for a clean appearance, but for identification you can choose from a selection of coloured luff pocket tapes for both mainsail and jib.
A, B and C rigs.
The black IOM insignia is applied as standard and you can choose, at extra charge, to have registration numbers and country designation letters clearly and neatly applied using one-time stencils and black permanent ink.
The sails are supplied with luff wires inserted and rolled smoothly between brown paper within 90 mm diameter cardboard shipping tubes.