Slocum`s Spray

Discussion in 'Sailboats' started by Elmo, Dec 19, 2009.

  1. Landlubber
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    Landlubber Senior Member

    An old saying, yet still very true, a good cruising boat is in the water, a good racing boat is on the water....everything else is a compromise.
     
  2. sharpii2
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    sharpii2 Senior Member

    Wow. That mainsail is huge. I can see why you went to a Chinese Lug. I like the fact that the biggest sail is where it is easily accessible.

    I've been trying to figure out what the original SPRAY'S displacement was. Some accounts say it was 36000 lbs, some say only 24000.

    From drawings, I have been able to guestimate the sail area of the original rig. The main sail was originally 750 sf, or there abouts. He probably had 400 to 450 sf total in the jib and staysail. This would give the original rig 1150 to 1200 sf.

    The cut down main was about 450 sf, the single jib was about 300, and the standing lug was 155. This gives the new sail area 905 sf, approximately. Does this sound right to you?

    This gives the old SPRAY an S/D of 13.1, if she was 36000 lbs, or an S/D of 17.2, if she was 24000 lbs, with the cut down rig. The lower number would certainly be considered under rigged. The higher one would be considered quite adequate by modern standards. Having a blunt bow and long, long quarter buttocks, I can see how this hull form would reward a huge rig more than a more modern form would. It seems that the newer 'open 60's' have a similar plan view. pdracer scows carry huge rigs with hardly any complaint. some have S/D s north of 25. Maybe it pays in the long run to have a blunter hull and a bigger rig. My own personal design ( see attachment) goes the opposite direction. It has a narrow hull, sharp ends, and a small rig. But it was not designed to win any races, but just to get me across an ocean with some degree of comfort.

    It seems that a lot of the rig cutting happened when he decided to round Cape Horn from east to west. Considering that the mast got the worst cutting, 7 ft and the already shortened boom was shortened further just to make room for the mizzen, it seems that Joshua was worried about windage and top hamper. You can reef the mainsail, but you can't reef the main mast. Perhaps he was readying his small ship to face fierce headwinds. Joshua was not that old when he set out. He was 51.

    Is BERTIE a scaled up version of SPRAY?
     

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  3. BATAAN
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    BATAAN Senior Member

    Bertie

    BERTIE is the basic lines of SPRAY, using the given outside of plank lines as the frame line, so she's 1 3/4 inches bigger all around, my plank thickness, therefore more displacement to compensate for a heavier hull construction (I don't like bent frames very much having to repair them so many times in my shipwright career). The transom is more upright and I went with an outboard rudder, very much like a Danish "Marstal" stern as used on Baltic traders. This gives a longer waterline and more displacement aft allowing me to flatten the buttocks an inch or so to compensate and improve the run even more. The travel lift operator looked at his strain gauges and told me "46,000 pounds" (with fuel and water and tools, inside ballast and etc) but I used the tugboat construction I was trained in with its sawn frames and very beefy scantlings so she's heavier than the original, but empty she rides quite high so the hull weight is not excessive. Andrade gives displacement of original as 562.80 cu ft., 36,072 pounds or 16.10 tons. Original sail areas are (the cut down rig): jib 246 sq ft, main 604 sq ft and mizzen 151 sq ft flying jib 160 sq ft.I have never calculated any of the design, just used rule of thumb and common sense from my practical experience, as I am not a trained designer. She even works and tacks in an anchorage under the main alone like a big cat boat, so I guess it all worked out. People look at the round bow (kind of like the end of a refrigerator) and wonder how it can sail at all, but the bow is quite shallow and fair and the water goes under, not around. Up to 6 knots she leaves virtually no wake, so seems very efficient. Pete Culler called wake making vessels "Mrs. Bruisewater", and when I see an over-driven modern boat leaving a huge wake I wonder how much progress we've made. Your simple dory-like design (is it flat, v-bottom or molded?) looks very practical and usable. My first design was a Saint Pierre dory designed as sailing cruiser. Never built it but I was working at Mystic Seaport at the time (1972) and John Gardner looked the design over and approved. Best of luck and keep us posted how it goes. I hope to get out of Port Townsend this summer and head up North but I have a gig working on Pirates 4 in July so that keeps me from a trip to the Queen Charlottes this year. I think Slocum was mostly reducing mainsail size when he cut the mast down, though of course the weight and windage were a factor, as I've been shipmates many times with large gaff sails..... that's precisely why I went with traditional Chinese.
     
  4. gggGuest
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    gggGuest ...

    Here in Britain you just have to look around the historical records and maybe walk around a few coastal churchyards and reflect that every storm came with its harvest of broken bodies washed up on the shore and husbands and fathers who didn't come back again.
     
  5. BATAAN
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    BATAAN Senior Member

    Absolutely. Most fishing boats were under 25', open, ballasted with stone, launched off the beach and fished in often marginal weather. In 1850 there were 500 shipwrecks on the coasts of the UK, not including hundreds of small craft. In November 1709 a two week gale wrecked 90 ships on the Goodwin sands alone. One morning the Deal Boatmen saw 200 men running around on the sands at low tide. A few hours later they were all dead as the tide came in and crashing surf prevented their rescue. Seafaring has always been dangerous and always will be. My experience tells me the SPRAY model, tightly decked and with small hatches down the center-line is safer than many craft. Like aircraft, most disasters are the result of crew error, not the vessel itself. In the days of sail, one was forced by economic necessity to make marginal seafaring decisions that all too often resulted in disaster. Again, observation from experience. Today, yachtsmen have the luxury of weather reports, GPS, good charts etc and in the US even food stamps so they don't have to worry about starving like so many UK poor fisher-folk and commercial sailors did.
    A UK fisherman was asked once about 1880 that since his father died at sea and grandfather, and great-grandfather, was he afraid to go to sea? He replied with the question where did your father die, "In Bed", and your grandfather? "In bed". So he replied, "then aren't you afraid to go to bed?"
     
  6. sharpii2
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    sharpii2 Senior Member

    It is really a 'V' bottom sharpie. or at least that's how it started out. The deadrise is substantial to make it easier to drive through the water. Another goal was to make her as easy to build as possible out of crappy second growth wood. She is to be built of plywood. In earlier times, she would have had a cross planked bottom to avoid splinter like plank ends. I often wonder if the old timer's would trade their straight grained, first growth timber for our epoxy. I wouldn't bet on it.

    Here, she is drawn with bilge keels which I think go well with her 'V' bottom. The objective was to limit draft and be able to stand when the tide goes out. I have since drawn a version with a long fin keel, but wonder if the lesser ballast needed justifies the deeper draft.
     

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  7. BATAAN
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    BATAAN Senior Member

    V-bottom sharpie

    Wow, looks good but might require considerable ballast, just from eyeballing the lines. Stone on brushwood (see Homer) works.
    Semi-Truck inner tubes, cut into thirds and ends of resultant curved "sausages" sewn shut with s/s wire, filled with gravel make wonderful ballast bags that; don't rot,
    don't slide around even at extreme heel and can be emptied or even thrown overboard in emergency at low cost.
    Remember that more deadrise=more tippy=more ballast always located as low as practical for the cost and also of course less weight anywhere above the waterline or the ends, especially in something you expect to rise to a breaking sea. This means keep anchors etc heavy things low and center and you're good to go. Bristol Channel cutter Pilots in the days of sail were reputed to prohibit the stowing of so much as an oilskin in the foc'sle. Seems extreme to me but I get the idea and when I moved BERTIE's anchors and chain aft and down the light air performance was markedly improved.
     

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  8. sharpii2
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    sharpii2 Senior Member


    It will have it.

    The keels are steel reenforsed concrete at 320 lbs appiece. The chain locker is in the deadrise aft the foreward bulkhead as are all the water tanks. Food will be stowed there as well, if possible. Aft the stern bulkhead will be where the outboard engine and fuel will be stored on a sole that slopes aft above the max waterline. There there will be a small hole for the gasolene fumes to drain out. The engine will be quite small, no more than 4 hp.

    Thanks for your comments.
     
  9. BATAAN
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    BATAAN Senior Member

    Small boat

    It sounds like your design is well thought out and simple, therefore easy (as a ratio of crew/ton) to build, maintain, repair and sail. Bon voyage and fair winds sailor.
    Note: the opposite of the above, the sailor's curse is- "big ropes and small blocks to ye, a rolling sea and rain..." use only when absolutely necessary.
    BATAAN
     
  10. sharpii2
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    sharpii2 Senior Member

    Small boat

    Thanks for your kind words, Bataan.

    My 'V' bottom 'sharpie' design (it's really too heavy to be a true sharpie) is really my first attempt at cylindric developement, where the planking matterial has only bend but no twist.

    A famous design using this method is the SF Pelican.

    At the time I started thios design, I did not know how two curved plates, canted at an angle would join together with no twist. I have since figured that out, so am now free to design boats with flaired sides.

    This project has taught me an awful lot about whysailboats look the way they do.
     
  11. BATAAN
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    BATAAN Senior Member

    boats

    It's such fun to use 1/8" plywood or stiff paperboard and build a half model on a backboard of any proposed sheet material design, shows what works and what doesn't as far as planking. Also full-on design models too. Dynamite Payson and Weston Farmer both have great books on boat design using paperboard models, like paraffin weighs the same as fuel so fill a model tank with it and the trim is right in scale etc. In my other life I was once a Special Effects Modelmaker at Industrial Light and Magic and besides the great fun of making a 20 foot wooden accurate scale brig for Pirates of the Caribbean 1, I got to build 1/4 scale dinghies out of lapstrake 1/8" ply and 5 minute epoxy. One's sitting on a bookshelf in my house still. Sheet goods, both ply and steel, can be distorted to give a slight 3d shape and avoid the flat sections. Again see Weston Farmer.
    Allen Farrell, the British Columbia boatbuilding guru and all around genius, developed his cruising boats with large sailing models, 3 or 4 feet long, to tune them for balance and trim before building the real thing. His boats like CHINA CLOUD are stunningly beautiful. I recommend this to any designer of small boats. You can see ugliness or beauty in a model, and change accordingly if needed.
     
  12. SAE140
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    SAE140 Junior Member

    A friend of mine builds steel Robert's Sprays in the range 36-42 feet, and I tend to get roped-in to help deliver 'em - so I can only comment on these versions.

    These particular boats don't so much sail, as wallow along - so as a tied-up liveaboard craft they are fine, as long as you stay on the Trades or are prepared to burn a lot of diesel when moving them around. As a sailing craft, they leave so much to be desired, it's difficult to know where to start. So I won't.

    I don't really know on what feature the attraction of these boats is based - although an association with a master mariner's epic voyage together with some astute marketing is undoubtedly responsible, at least in part.
     
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  13. rwatson
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    rwatson Senior Member

    Are they particularly easy to build or something ? Maybe being hard chined and boxy shaped they are easy to cut out and weld.

    What does your mate think of the building side of things ?
     
  14. dskira

    dskira Previous Member

    So true. Very well said.
    Daniel
     

  15. SAE140
    Joined: Apr 2010
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    SAE140 Junior Member

    He builds 'em because they're easy to sell - in fact each hull is usually sold before completion.

    They're not particularly easy or difficult to build - just laborious. Framing, jigging (for ease of turning), then miles and miles of welding.
    If you want an easy-to-build hull, with a good sailing reputation, have a chat with Brent Swain.

    I've attached a couple of graphics of a 38 (stretched 36) in the process of being turned over - so that anyone contemplating building a Spray can get a feel for the size of the project.
     

    Attached Files:

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