Sunday II is in the water and now she is waiting for her rigging. The Hunter sailboats have long been known for their unique sail layout. It is know as a B&R rig. Here are the highlights.
“Designed by the late Lars Bergstrom and Sven Ridder, the B&R rig eliminates the need for a backstay to allow for a more efficient mainsail shape. Fixed backstays are often omitted from the designs of today’s performance-oriented boats to allow the mainsail to incorporate a full roach design — a more aerodynamic shape both for racing and cruising performance.
The B&R rig has 30-degree swept spreaders, creating 120 degrees between each rigging point. The result is a tripod arrangement, used for years to support huge radio towers, that has excellent strength for sailboat rigs.
While conventional rigs often lead their shrouds inboard to allow for the large genoa overlap, Hunter takes them far outboard to the hull. This wide chain plate base significantly reduces the compression loads to the deck and hull, while allowing for tighter sheeting angles. The smaller headsail sheets are inside the spreader base.
The latest advancement to the B&R rig is the addition of mast struts. These struts stabilize the lower section of the mast, allowing compression loads to be spread and reducing the point loading at the mast base. They create a strong point for the boom and spinnaker pole loadings. The struts also allow us to use a smaller mast section reducing weight aloft to decrease the heeling and pitching moments, making for a more comfortable ride. Additionally, they provide a secure handhold when going forward.
The B&R rig is also supported with the addition of reverse diagonal rigging. For example, the diagonals beginning at the top of the mast strut and ending at the tip of the spreader support and stabilize the lower section of the mast by creating a triangle with the upper shroud. This allows us to induce the mast’s pre-bend prior to stepping the mast. Similar to a sailboard, the pre-bend is loaded within and does not deliver pre-bend compression loading to the hull and deck.
The B&R rig is designed to be pre-bent to further add rigidity to the mast section and eliminate the need for adjustable rigging (like backstay adjusters, babystays and runners). This design should prove more reliable than a rig with adjustable backstays or runners, as there is less chance for error.
The large main, small jib sailplan on these Hunters also eliminates the need for large overlapping head sails, since the driving power comes from the much improved shape and size of the mainsail. This allows for an easier tacking small jib, creating good performance and more comfortable sailing — and less work for the crew. It is far more aerodynamically efficient to reef the main than furl the head-sail. Plus it provides better balance from the rig and more control for the rudder.
With the large main creating additional main-sheet and leech loading, Hunter has placed the main-sheet atop a cockpit arch on many models. The main-sheet loads are placed at the same location as the leech loading to reduce the bending loads on the boom. The main-sheet loading is also reduced, allowing for easier control of the mainsail. The arch also serves as a handhold while in the cockpit as well as an attachment point for a Bimini top. “