Thinking about a motorsailor

Discussion in 'Motorsailers' started by 8ball, May 17, 2015.

  1. RHP
    Joined: Nov 2005
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    Location: Singapore

    RHP Senior Member

    I love Tad's work but I'd keep it simple per the Nonsuch 30.

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  2. philSweet
    Joined: May 2008
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    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member

    Two different ideas being discussed. A stabilizing sail is great if you need one, but I'm not sure how relevant one is for a great loop boat. Setting a sail up for stabilizing duty in open water is very different than setting up a sail for confined waterways. A large, high twist genoa would seem just the thing for a heavy bug boat coming home. But not what I would want on the Mississippi.

    For the great loop, you would want to put emphasis on striking sail and mast completely. You want very good visibility under sail, and you need to be able to trim the sails frequently with little power. All things a genny is not.

    I'd use a cat ketch or cat schooner rig with as much distance as possible between the masts, and masts that are only about 20' tall in a simple deck mount. I'm thinking something that looks like a couple Hobie Wave rigs would do. Roller furling booms and the booms slide in the sail track so you can roll and reef the boom up the mast leaving the sail topped out. Now you can see under it.

    What engine do you have?
  3. phillysailor
    Joined: Nov 2012
    Posts: 21
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    Location: Media, PA

    phillysailor Junior Member

    I’ve been experimenting with a twin keel balanced rig design. The goal is a KISS shallow water capable coastal cruiser for a couple doing the Great Loop.

    Master stateroom with queen berth forward and closets P&S. A pilot berth/office/laundry room to port with hanging wet locker under the companionway. Lavatory to starboard and a shower with walk through to an engine room with 5’ ceiling. Work bench & spares to starboard, seating on the small genset cover.

    Steps to the port of midline up to a narrow cockpit with generous coamings P&S, and a threshold at the top of fore & aft sets of stairs. Two captains chairs to starboard and a forward facing bench to port. Steering near midline and a single winch outboard handling the powerful vang and the mainsheet: the only sail controls necessary for this type of rig. A windscreen and a hardtop dodger protect the crew who travel with exceptional visibility and in the center of the boat. Solar panels would be placed atop the hardtop, and to starboard above the master stateroom coachroof.

    Aft from the center cockpit, through another companionway (hatchboard disappears downward, like the Halberg Rasseys) is the dining area, with diner booth seating to port (converts to a berth) and a generous galley to starboard. Under the sole are batteries, tanks and stores. Continue aft through a door to an immense back patio with cooking station and an open stern facilitating immediate and easy launching of up to a 10’6” dinghy. Storage under the cockpit sole and underneath the coamings which continue forward P&S allowing quick movement around the whole boat.

    Up in the bows is a split level anchoring and sail handling workstation: it’s higher to stbd where an off-center vertical windlass allows it to handle the anchor on the starboard bow, raise the mast, as well as haul the halyard for the largish sail. (Are these additional uses for the windlass ok? Trying to reduce costs.) Having the windlass raised permits the anchor to sit higher in the bow and allows the chain to fall to a self draining locker. Crew can stand in greater protection behind the bulwarks on the lower deck to port when anchoring & reefing.

    The tabernacle allows the mast to fold atop the hardtop and supports the oversized Vang (and possibly the gooseneck.) Single line reefing lines to two reef points and outhauls for the main and the first reef complete the simple rig.

    Engine approx 75hp with Variable pitch prop in clear flow (no obstructing keel), protected by a small skeg. A skeg hung rudder facilitates drying out on a beach with the twin keels.

  4. phillysailor
    Joined: Nov 2012
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    Location: Media, PA

    phillysailor Junior Member

    for those interested in little details...

    Up top is a quite possibly difficult to understand sketch of a gooseneck made of nylon webbing around the boom capturing a ballistic nylon sleeve which can slide fore and aft via a 4:1 or a 3:1 two line control system labeled "Boom Aft" and "Boom Fwd". Next to the mast, this sleeve has two dyneema soft shackles. One of the shackles loops from _forward_ of the mast to curl around the back of the mast mast to meet the ends of the _aft_ shackle. Each end locks into the contrasting ends of the other: diamond knot aft shackle goes into constrictor of forward shackle, and vice versa. These shackles pass through blocks used in the purchase system for the fore and aft boom control lines.

    This inexpensive system allows the boom to be slid fore and aft against the mast, necessary for adjusting the center of effort of the balanced lug sail while sailing. For instance, when running before the wind, pulling the boom forwards balances forces against the mast, rather than pulling the boat's balance over towards the boom. Tightening the fore & aft boom control lines also pulls the boom against the mast, using the two shackles as a constrictor. The ballistic nylon would serve to protect the dyneema shackles which, with the nylon webbing, carry the sailing loads. The nylon sleeve would route the dyneema to avoiding it bring crushed between mast and boom, and the nylon would (not shown) somehow be secured into a HDPE bearing surface. (Not quite sure on that specific but yet)

    Secured to the front of this nylon sleeve, running around the boom and down the front of the mast with a 4:1 purchase is a "Goose Vang," which sets the height of the gooseneck. The angle of the boom would be maintained by a rigid vang, which would also help support the boom when the mast was down, resting atop the cockpit hardtop.

    Other running rigging lines include reefing control lines, which I envision coming down from cringles fore and aft and then meeting while running forward. By joining in a "Y" the two lines can be pulled down together the same distance. The full sail and the first reef would also have outhauls attached: the clew would have a strap around the boom, and the block for the first reef would be on a similar strap free to be pulled aft when "Out 2" was tensioned. The second reef would be permanently mounted for a tight foot. Reefing would be done at the mast, where the halyard resides. Fine sail controls (and the mainsheet) run to the cockpit.

    The forward portion of the boom, and the bottom portion of the mast would be made of aluminum, with an internal sleeve stiffening the area where the gooseneck would reside. The aluminum would better withstand the resulting abrasion and considerable side forces better than carbon fiber, which would be better suited to the longer aft and top sections.

    Because of the open aft deck, provision could be made for a cassette-type rudder to drop over a 1" pin into a purpose-made socket. The tiller for this emergency rudder could be bent to lift it off the deck, possibly using a tiller extension to improve visibility. The blade would be removable to facilitate storage. A detachable outboard motor mount could allow the dinghy motor to provide emergency power.

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