What is the standard rig and sail inventory for a Hallberg-Rassy Monsun 31?
I am looking at buying a 1977 Hallberg-Rassy Monsun 31, but the current owner has replaced and removed a few things over the years. What did these boats come with originally from the factory in terms of the mast, rigging, and sails? I want to know if the current setup is standard or modified.
Answer
The Hallberg-Rassy Monsun 31 was built as a masthead sloop featuring a deck-stepped Seldén aluminium mast with single in-line spreaders. The factory standard sail inventory included a 21 square metre mainsail and a 30 square metre No. 1 genoa.
Standard Seldén Spars
The Monsun 31 was fitted exclusively with Seldén spars between 1974 and 1982. The mast is a thick-walled aluminium extrusion stepped on deck. Beneath the deck, the compression load transfers to the keel via a solid mahogany support post. The rig uses single in-line spreaders. Because these are not swept aft, the boom can be let out fully when running downwind without chafing the mainsail. The standard boom came equipped with simple slab reefing, and the spinnaker pole was usually stowed vertically on the leading edge of the mast on a sliding track.
Standing Rigging Specifications
The classic masthead design requires heavy support. The factory standing rigging layout consists of a forestay, a single backstay, twin cap shrouds, twin forward lower shrouds, and twin aft lower shrouds.
The original wire was 6mm 1x19 stainless steel across the board. This terminated in swaged eyes secured with Hasselfors bronze rigging screws. The backstay is a single wire down to a bridle or a mechanical backstay adjuster just above the transom. When inspecting a new purchase, always check the mahogany mast support post below decks for signs of compression rot before tensioning the rigging. Many owners upgrading for offshore passages upsize the forestay and cap shrouds to 7mm wire. The standard 6mm remains perfectly adequate for coastal cruising.
Original Sail Inventory
Olle Enderlein designed the Monsun 31 to be a stiff boat. The sail plan reflects this with a modest total upwind sail area of around 41 square metres. If you ordered a fully kitted boat from the yard in the late 1970s, the sail bags contained:
- Mainsail: 21 square metres, originally cross-cut Dacron with short battens and two deep reefing points.
- No. 1 Genoa: 30 square metres, designed to overlap the mast significantly. Originally a hank-on sail.
- Working Jib: 18 square metres, cut high on the foot for visibility and heavy weather beating.
- Storm Jib: 7 square metres, heavily reinforced.
- Spinnaker: 65 square metres, symmetrical, flown with a conventional Seldén pole.