Sloop to Cutter Conversion

Discussion in 'Boat Design' started by CheoyLee67, Jul 23, 2013.

  1. CheoyLee67
    Joined: Jul 2013
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    Location: Eastern CT

    CheoyLee67 New Member


    This is my first post in this forum so excuse me if this topic has been covered before. I have a 1967 Cheoy Lee Offshore 36 designed by Maurice DeClercq that I'm restoring. The full keel hull and deck have been surveyed and are in good dry condition. It needs new spars which I will build in wood and the interior needs rebuilding so it is a blank slate to build into a offshore yacht. I hope to do a trans-atlantic trip. Inspired by the Lin & Larry Pardey and Lyle Hess, I'd like to convert this boat to a cutter rig with a similar sail plan as used on the Pardey's Taleisin. Taleisin has a 105% jib, staysail and battenless mainsail as standard sails. Larry Pardey recommends 80-90 square feet of sail per ton for good light air performance. I would like to have a bowsprit/anchor platform and running backstays would be OK. Chainplates would attach to the hull. By the way this boat does not have engine. This link has info on the Cheoy Lee:

    I'd like to hear from other owners who have done this and from designers as to what is involved and how many hours it would take to do the job. I have extensive woodworking experience, a well equipped shop and some rigging experience so I plan to do most of the work myself. Thanks!
  2. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    The easiest ways to make a cutter, is to either have the halyard at the spreaders for the jib, or both halyards close to the head of the mast. Both setups avoid running back stays.
  3. alan white
    Joined: Mar 2007
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    Location: maine

    alan white Senior Member

    I've converted a boat from sloop to cutter. What matters most is balance of course. My boat was 23 ft and about 3800 lbs displ.
    I didn't do it for reasons such as yours. I did it because of a wicked weather helm. I added 28" of bowsprit. The staysail attached to the mast at about 7/8 height.
    I mostly ran a 130% jib with a wire luff which furled but did not reef. The wire stay with the jib wound around it stored nicely along the deck when furled. The staysail (on hanks) was on a wishbone rig so it self-tended. About 140 sq ft..
    Here's your potential problem: While you most likely have a better balanced hull than I did, and while my own boat ended up with a very managable lee helm in very light conditions (going to moderate weather helm when it piped up), it's easy to play such game (I didn't hire a designer), a much larger boat (8 tons?) should be redesigned by a real expert $$$ because so many factors come into play---- especially balance, which in your case would cause the boat to fall off in a gust rather than round up.
    In other words, if you balance well now you might consider keeping the sails all inboard, omitting a sprit, which will guarantee your helm will remain similar.
    Of course there are all kinds of tricks to overcome a lee helm should it be a problem (A one foot sprit wouldn't have as much impact as a six foot one). The problem is cost. It might be suggested that you add some forward underbody area, or lengthen the
    boom and the mainsail. All expensive and/or labor intensive.
    I guess what I'm getting at is cutters are perfect for some people but when you convert from a sloop to a cutter, it's definitely a lot simpler to keep the sails inboard, meaning a means of attaching the inner jib a ways back somewhere where a rod might divide the accomodations below such as piercing the vee-berth with a stainless rod. either that or build a lateral brace or bulkhead depending on design.
    If you presently believe you have a heavy weather helm, a bowsprit will cure it. If you balance well now, forget the sprit. Classic bow-spritted cutters that are born cutters have underbodies that are balanced to a rig with a sprit.
  4. michael pierzga
    Joined: Dec 2008
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    Location: spain

    michael pierzga Senior Member

    Your boat has a fractional rig. This makes it perfect for using modern CODE type headsails. Id skip the cutter rig and fit a mini bow sprit to accommodate the tack of the new sail.

    These Code Sails are a major advance. They are powerful , versatile because they handle a wide range of wind angles while being easy to handle.

    Double Check that your rig and rigging are up to the task
  5. bpw
    Joined: May 2012
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    Location: Cruising

    bpw Senior Member

    The Pardeys are great sailors, but there books are 30-40 years old now.

    Lots has happened in the meantime, so do some other research before making your choices. The Dashews have some very interesting ideas, polar opposite of the Pardeys, but well thought out.

    I sail a heavy, 28 foot, full keel, engine-less boat and would never give up my full batten main. Chafe issues with the full batten are a non issue, especially with synthetic rigging. And the sail is far more powerful, especially in light air since the battens maintain shape instead of the sail hanging limp. General consensus among sailmakers these days is that full battens retain shape the longest.

    My boat is an extreme fractional rig with masthead asymetrical spinnaker. Jib is only 80 square feet, main is 300. Works pretty well in a cruising context. Main gives lots of drive off the wind, no big headsails to deal with. but hard to power-up in light airs up wind. I plan to buy a light masthead jib for beating in 8-10 knots and under.

    Starting fresh you have all kinds of options for swept spreaders, fractional with masthead spinnakers, free flying storm sails on dyneema luffs, lightweight un-stayed bowsprits for reaching sails etc...

    But in reality you will have no idea what you want until you sail a few thousand miles, so by the cheapest used rig you can find that will work for the boat and go sailing.

    Or maybe by a different boat that is already complete. A new rig and sails will likely cost more than a complete cheoy lee 36.

    Also, your Choey Lee with that big overhang on the bow will hate the weight of a bowsprit.

  6. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    The Pardeys also have very peculiar ways of looking at things. Generally they are in favor of most old, well founded stuff, but dislike or distrust anything conceived in the last half of the 20th century. Maybe this is the path you want to go down, but the majority of sailors are perfectly comfortable with the advancements made. Comments like using hollow leach battenless mains and his general disdain for anything he can't understand, makes you take what his books suggest with a grain of salt, possibly the whole salt shaker.

    The only real way to know how to setup your boat is to use it. As you get experience, you'll make adjustments, which will evolve in time as your experience develops favoritism.

    A cutter requires the mast move aft, usually a good bit. Do you really want to do this? A cutter rigged fore triangle is a different beast and probably what you have in mind. This keeps the mast in the sloop location, but divides up the head sail area into a couple of smaller sails. This is done to keep sail sizes manageable, but with modern roller setups, less desirable then you'd think. A double headsail rig, isn't as efficient as a single jib. It adds complexity and weight to the rig too. Often the "baby" stay is "hooked" so it can be moved inboard, against the mast usually and in light air, you can hoist a big genoa. As the need for this sail becomes less desirable, you can roll it up, rehook the baby stay and hoist a better combination. This is a much more logical route then moving the mast, maybe putting sprit on and redesigning the whole rig. You'll still need to arrange some support for the baby stay, but this is a lot easier to go the double headstay route.

    I've had a couple of Choy Lee offshore 35's, one factory yawl rigged the other upgraded to yawl. One had a double headsail rig, the other just a jib. The jib boat was closer winded and faster. The double headsail boat had some additional heavy air options, but generally the baby stay wasn't necessary in this size boat, with modern furling gear. These old school CCA style of yachts sail well and comfortably, but anything you can do to improve efficiency will reward you.

    What I'm saying is be careful what you wish for. The double headsail rig can be handy at times, but most of the time it's just extra wight, extra windage and additional contrivance to contend with. If you insist on a true cutter rig, you'll need a professional work out the details, which are numerous. Chain plate relocations, baby stay location deck reinforcements, a whole new spreader and lowers configuration (at least), new back stay arrangements, new mast step hull reinforcement, new partners and their reinforcement, plus other localized hull and deck reinforcements - the list can get extensive. Yeah, you want a double headstay rig, not a cutter.
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