JoeBoat Alana

Discussion in 'Sailboats' started by sharpii2, Nov 1, 2020.

  1. sharpii2
    Joined: May 2004
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    Location: Michigan, USA

    sharpii2 Senior Member

    After many years of playing with boat design, I have decided to finally take the plunge into the designer/builder realm.

    I have decided to build a boat of my own design.

    If this boat proves itself, I'm seriously considering creating a class based on its design.

    The design is what I call a "JoeBoat" (named after my long deceased brother). It is a concept I have long ago wanted to try. It is a straight-sided scow with a 3.0 ft Beam and a deep-rocker bottom.

    I have drawn four versions of this concept, complete with full parts drawings.

    It started out as a 2.5 ft x 10 ft boat, then morphed to two 3.0 ft x 12 ft versions, then finally became a 3.0 ft x 10 ft boat, the one I decided to build.

    Not content to build just a hull and put a conventional rig on it, I decided to also try a sail concept I have been kicking around for many years, too.

    I have been wanting to try a split-lug for as long as I can remember.

    A split-lug is a lug sail that is split into two smaller sails which share a boom and a yard. The aft portion is laced to the mast. The forward portion is free standing in that it only attaches to the boom and the yard.

    There are two supposed advantages to this arrangement:

    1.) there is no chafing against the mast on the "bad tack", as there is far less of one. The boom and the yard are still on one side of the mast, so there is a difference in tacks, but the sail cloth does not have to bend around the mast.

    2.) A larger portion of the sail area can be in front of the mast. This will be useful for better down wind manners and less violent jibes. It also will allow the mast to be stepped further aft, which will be quite useful on a tiny boat.

    A big disadvantage, however, is reefing.

    If the sail is to operate properly, the luff of the forward part must align properly with the leech. And the leech must align properly with the luff of the aft portion. Once a reef is tied in, this alignment can go to Hell.

    As a solution to this problem, I added a second boom to define the upper portion of the reef slab.

    This effectively creates another pair of sails, a lower forward portion and a lower aft one. By lowering the top boom onto the lower one, the sail is quickly reefed--providing lazy jacks are used.

    It will share this characteristic with a Chinese lug .

    As for the hull.

    The idea is to have a shorter WL when the boat is dead upright and a longer one when it is heeled.
    Also, the boat can heel quite a bit before the bow transom corner digs in.

    A further advantage is that it can be ran up to a bank and be more easily be pulled up it.

    For deck layout, I decided to board over the bow, so the side-decks run straight up to the bow transom, and there is no fore-deck. This way, I don't have to climb over the rudder, or unship it, every time I board.

    The mast is stepped through the starboard side deck, so it becomes a handy hand grab instead of an obstacle.

    So far, I have built the rig (which I hope to show below), and I have fully lofted the hull.

    This will be the first boat I have built in over 40 years.


    FinishedRig.jpg Alanna3.png Alanna2.png
     
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  2. bajansailor
    Joined: Oct 2007
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    Location: Barbados

    bajansailor Marine Surveyor

    Some thoughts :
    Your beam is only 3' - methinks she might be a tad tippy?
    Your rig looks rather complicated - you effectively have to make 4 sails (although the two forward ones are just glorified pocket handkerchiefs).
    With the mast stepped through the starboard side deck, this would work very well for sailing on port tack - but you won't be able to 'sheet in' very much on starboard tack without the boom bashing you.

    Re creating a class, I admire your optimism - but I think I would prefer something like a Minifish any day - this is essentially a smaller version of the Sunfish.
    https://sailboatdata.com/sailboat/minifish
    11'9" long, and 3'10" wide - that extra 10" will have a huge effect on the stability, never mind that she has a pointy bow.
    Oh, and they apparently built 14,000......

    In the 70's we had a popular home grown class called a Kingfish here in Barbados - it was very similar to the Sunfish (it used the same rig), but built of wood with a bluff square bow, and with no cockpit at all - you sat on it, rather than with your feet in a well. And it was a very popular and competitive class here, but I cannot find any mention of it online.
     
    Last edited: Nov 1, 2020
  3. messabout
    Joined: Jan 2006
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    Location: Lakeland Fl USA

    messabout Senior Member

    Looks like a PDR that has gone to school. A Narrower, longer, more symmetrical rocker. The sail................? a PITA on first impression. Until you persuade me, I am wondering why I need to mess with additional control lines for so tiny a boat. At 36 inch beam it will be nervously tender unless the sail is kept too small for meaningful drive. . Increase the beam to 40 inches and gain a lot of stability both initial and heeled. This kind of boat will have some exaggerated section centroid alignment problems when heeled at moderate degrees.. 5 8, 10 degrees.

    Aside from all that criticism, I like the boat but not the sail. The sail is inventive so I defer to your judgement. Carry on, this is interesting.
     
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  4. sharpii2
    Joined: May 2004
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    Location: Michigan, USA

    sharpii2 Senior Member

    Thank you bajansailor for commenting on my design.

    The narrow beam is somewhat deceptive. This is because stability comes from average beam, not maximum beam.

    Stability also comes from Vertical Center of Gravity (VCG) placement. The seat in this boat is just 6.0 inches above the bilge. If it were higher, the boat would indeed be tiddly.

    The sail plan is also modest, even considering the narrow beam.

    The sail, indeed, is a concoction. It is based in principle on a sail I made over forty years ago. It was to power a four-man raft I had turned into a sailboat.

    The sail proved to be surprisingly effective, especially to windward. It was made of plastic and duck tape, but out sailed a grp dinghy, of similar size and weight, to windward.

    I was quite surprised. The race was suppose to be a a joke. This other boat had a dacron sail and a proper dagger board.

    Mine had home made sails and twin boards whose blades were longer than they were deep.

    The theory is that the "handkerchiefs", in front of the mast, will direct air flow around it, so there is less turbulent flow.

    I do have an exit strategy should this not work out.

    I have already designed a more conventional balanced lug, which will have similar area, and use three of the four spars.

    I do remember a plywood board-boat which used the sunfish(r) rig. And it didn't have a foot-well, and it had a square bow.

    Sunfish(r) were a bit pricey back then, and I suppose this plywood boat was a build-it-yourself alternative. I remember seeing a lot of them around.
     
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  5. sharpii2
    Joined: May 2004
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    sharpii2 Senior Member

    Thanks, messabout. I do remember the PDR days. I used to hang out there a lot. I even designed two PDRs myself.

    Only 4.0 additional inches of beam will improve the stability more than one would think.

    But if the boat already has sufficient stability, why add more?

    Granted, the sail drawn has relatively modest area for a dinghy, and greater beam and a greater sail area would certainly improve the performance over a greater range of conditions.

    But I do belive both are sufficient for my purposes.

    This is not intended to be a pure sailboat. There are plenty of them around (and probably designed by better designers than myself).

    Much of the time, this boat will be propelled by muscle power.

    If there's not enough wind for proper sailing, I want to go boating, damn it.

    Maybe I can drown a few worms then and bring back my supper.

    I don't see a problem with the centroid issue (of course I can be wrong). What I may end up with, when the boat heels, is an asymmetrical catamaran hull, with rhe flat side of the "V" bottom to leeward, where the drive of the sail will be (at least on the port tack). The flat side may also provide enough effective lateral area to allow forgoing the 'board. But the rig may be too far forward for this.
    But I will try this when I do sea trials.

    Yeah, the rig may be a bit much for a tiny boat. It does seem to be damnedly complex. I sure felt this when making the extra spar, the four separate panels, and the lazy jacks.

    But only one extra step is added for set up time, and once the various leeches and luffs are aligned (which will probably have to be done only once when the sail is first used), the sail may prove easier to use.

    Reefing will be possible while still out on the water, and maybe even while under way.

    With a more conventional rig, the boat would probably have to be beached first.

    Besides, this can be seen as scaled down test of concept for a larger sail in the future.

    Even at its present size, I can imagine two of these on Sven's ExLex, instead of the two rectangular balanced-lugs he has now. These would almost double his sail area while making reefing a whole lot quicker and easier.
     
  6. sharpii2
    Joined: May 2004
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    sharpii2 Senior Member

    So now for an update.

    I've lofted the hull, cut the timber peices that will make up the frames, drawn the plywood parts on three sheets of plywood, and now have cut out the parts.

    I am far from being the best craftsman. If I were to rate my work, I'd give it anywhere from a D- to a D+. I suppose that's part of the point of the whole project. To see if I can build it. If I can, just about anyone else can. At least that's my reasoning. I am building it inside my house trailer in a 11.5 x 10 ft space. And I'm doing it with a very limited collection of tools, which include:

    1.) a 3/8 inch reversable drill,
    2.) a saber saw (sometrimes called a "jig saw"),
    3.) three chizels,
    4.) six 3" "C" clamps,
    5.) three home made sanding blocks,
    6.) a square, and
    7.) a steel 36 inch ruler.

    I used an 8ft long piece of 1\4 molding to draw the bottom curve.

    below, I have attached a profile veiw, and a plan veiw, to remind people of what I'm trying to build. Also attached is a picture of the cut out plywood parts.

    I have found the building process both very frustrating and very gratifying. It's frustrating in that I make a lot of stupid mistakes. It's gratifying in that I get to see real results from my efforts (though they may be far from perfect), something which is not often true with the other parts of my life. And I get to bring into this world something I have created with my imagination. I'll get to see how well or how horribly it works. If it at least floats, I will have a boat, something I don't have now. And I'll have one that I can keep in my house trailer.

    There are a number of highly experimental ideas in this design. One of them is the sail. It my work out reasonably well. It may work out better than expected. It may prove to be a disastrous miscalculation. If it proves to be the third possibility, I plan on making a balanced lug, which uses three of the four spars.

    The other experimental idea is the hull design.

    Unlike some scow designs, it is intended to sail somewhat heeled. This way, the leeward side and the bottom form a "V" section and an asymetric waterline with the long, straight portion to leeward. I imagine this will help the boat track better while on a tack. When changing tacks, the waterline shortens, and the rudder, far aft, has a lot of leverage to turn the boat quickly.

    If it works as I hope it will, it will be a bit of a revelation in performance. If not, it will end up being a 7 something foot tub crammed into to a 10 ft hull. If that turns out to be the case, I may be a bit sadder and wiser, but I'm well aware of the possible consequences and am willing to live with them.


    Alana 3.png Alanna2.png plyCuts.PNG
     
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  7. messabout
    Joined: Jan 2006
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    Location: Lakeland Fl USA

    messabout Senior Member

    I am anxious to see how this works out Sharpii2. Surely it is too damned cold in Michigan to be building boats except in a nice warm cellar or heated workshop.

    Keep us informed of your progress.
     
  8. skyl4rk
    Joined: Aug 2006
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    Location: Lake Michigan

    skyl4rk Junior Member

    Your sail should work fine. As someone that has built "too narrow" boats, I agree with others that an increased beam would add stability. Build it, have fun with it, tip it over, get wet. Its part of a learning experience. In any case it will be a good paddle platform to play on the water. Good for you to dare to design and build what you drew.
     
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  9. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    All scows are designed to sailed heeled. Unless they are going downwind. However, after you build the boat, race against similar size boats and see how it performs.
     
  10. Dolfiman
    Joined: Aug 2017
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    Dolfiman Senior Member

  11. sharpii2
    Joined: May 2004
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    sharpii2 Senior Member

    Racing it against other 10 footers, that are designed primarily to be sailed, would be like racing a battleship against a destroyer.

    The other boat will always be faster. But it wouldn't meet my other requirements, especially the storage one. But, that being said, it may punch above its weight. It may be able to do 5 to 6 knots in ideal conditions. A dinghy of comparable length might be able to do 7 to 9 knots, or even more.

    Pdracers (also scows) are always sailed upright if possible.
     
  12. sharpii2
    Joined: May 2004
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    sharpii2 Senior Member

    Time for anpther progress report.

    I have finished gluing together the hull sub- assemblies. These include: the two inner frames and two transoms, the butt joined sides, the aft deck and side deck joined together, and the three bottom pieces, with butt sheets glued to them. (see attachments below).

    This is the order I'm following to build the hull:

    1.) Loft the profile, plan and frame sections.
    2.) cut the timber frame pieces to size.
    3.) plane the appropriate bevels into the frame bottom pieces.
    4.) loft and cut out the plywood parts.
    5.) glue the frame pieces together, and add all the gusetts
    6.) Glue the side pieces together with their butt joints, and do the same with the three deck pieces. And glue the butt pieces to two of the three bottom panels.
    (these are the steps I have completed so far).
    7.) glue the sheer clamps and side deck stiffeners to the deck assembly.
    8.) glue the transoms onto the deck assembly.
    9.) glue the sides onto the deck assembly.
    10.) glue in the inner frames.
    11.) install the chines and pray the scarf joints I made in them don't fail.* These will be added without using epoxie. They will be screwed and nailed in temporarilly. Later, pegs made from bamboo scewers, will replace them. I will use "PL 350"(r) as the glue.
    12.) install the keelson, and pray its scarf joint doesn't fail. This will have to be scerewed in at the ends. I will use epoxy here.
    13.) install the bottom panels, starting at the bow. The bow panel has butt pieces glued on, as does the mid bottom panel. I will use epoxy at least at the butt joints. I may be able to use it on the chines and keelson as well. The main limitation is the limited pot-life of the mixed epoxy. Because I am adding shorter pieces, instead of the whole bottom at once, I may have enough pot-life time for each batch of glue. I also decided to use this approach incase I don't get the two sides to perfectly match in shape. I may end up with some ugly seams, but the objective here is to complete a useable boat. I will first tack the corners on with screws. If the edges follow the curve of both sides, I will then temporarily screw the middle of the panel to the keelson, then do the edges. The next panel will not be added until the preceding one is completely installed. I have cut the bottom panels so the outer grain runs from side to side, rather than end to end. Doing this is supposed to make the panels easier to bend and to make them stronger. I put the two butt joints in the open front end of the boat, where they will locally stiffen the plywood in areas I'm likely to stand in.

    In the mean time, I will be assembling the rudder and lee board.
    Also, some of the parts will be painted before installation.

    I have found that it is more difficult for me to cut accurately and glue accurately than I anticipated. Also, I seem to be unable to drill a sufficiently vertical hole without a drill press. There is a lot to be said for decent building skills.

    * If they fail, I will make new ones using butt blocks. The butt blocks will be at least 10 inches long, and tapered down by at least two thicknesses, maybe three. And If I have to use them on either the chines or the keelson, I will use them on both. I will line them all up evenly and put up with a flat area in the bottom.



    Fr+tra.PNG Fr+tra.PNG Dek+Sides.PNG BotWBtJts.PNG
     
    Last edited: Mar 26, 2022
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  13. sharpii2
    Joined: May 2004
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    Location: Michigan, USA

    sharpii2 Senior Member

    Here's a brief progress report:

    I have gone ahead and assembled the appendages, meaning the lee board and the rudder.

    The rudder has a home made hinge in place of the more traditionional gudgeons and pintles (see attachment). This hinge is made up of two pieces of 1 x 2 on the rudder and two 1 x 3 blocks on a false transom, which I call the "rudder plate". The rudder plate has two bronze door hinges on it that will attach to the stern of the boat. The rudder plate and the rudder swing down to put the rudder blade in the water. It swings up to pull the rudder blade out of the water, sort of like an outboard engine. This way, the rudder can kick up and still be a one piece unit. I will have two control lines to swing the rudder blade up and down. The down line will attach to a piece of shock cord which will be attached to the bottom of the boat. The idea is to slide the boat into the water stern first, then board it oover the open bow. Because the boat is so narrow and its bottom is so swept up, I need to be able to raise and lower the rudder remotely. This is the best sytem I could come up with.

    Using a sureform plane and a sanding block, I put foil-like edges on both the rudder and the leeboard. The leading edge of the rudder is only rounded. its trailing edge is has a rounded taper to about half its thickness. The edges I put on the leeboard are the same on both ends. They resemble the trailing edge of the rudder, except that the last 1/4 inch is rounded. This is because the lee board swaps ends when it is move to the other side of the boat, when changing tacks.

    The rectangular object in the pickture is the seat that I will sit on. It will sit on two wooden rails, so it can be slid forward and aft. This gives me some flexibility in teriming the boat fore and aft. I can also make another seat for a guest. being able to change the trim so easily might enable me to to sail upwind without the lee board. I will definitely try that, once I get used to sailing the boat.

    Next to the seat is the stack of both transoms and both internal frames. These were not as well made as I had hoped, and will need some "adjustments" before they are ready to go into the boat.

    I have glued most of FinAppen+Fra.jpg this together with epoxy.

    I have found that it takes a lot of coordination and timing to use this stuff efficiently. Both surfaces have to be first coated with the glue alone. Then one of them gets the epoxy mixed with structural filler. Then they must be joined together accurately and held in place. After much trial and terror, I have taken to using sheet rock screws to hold the parts together untill the epoxy is nearly hardened. Then I remove the screws. This way, I can pre-assemble the parts before mixing up the batches of epoxy. I used this method to build the yoke assembly, the rudder assembly, and the leeboard assembly. This is the best method I can come up with so far. I am reasonably pleased with how these came out, though there were quite a few glue bugers that I missed. Those are what the sanding block is for.

    That's it for now. Soon, I will be gluing the deck assembly together, then adding the transoms and the sides.
     
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  14. sharpii2
    Joined: May 2004
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    Location: Michigan, USA

    sharpii2 Senior Member

    Progress Report.

    I now have the deck assembled and have set up the transoms and frames on it. Since the deck is dead flat, it doubles as a construction jig.

    In the mean time, I have drawn a second version of this boat with the deck at the bow instead of the stern. This will require the sailor to sit facing aft. This would be better for using oars or the single short sweep I have planned on. The downside is looking over one's shoulder to see where one is going.

    I also drew a two piece rudder that is offset and controlled by a push-pull shaft rather than the pull-pull steering line I will have on my boat. (see attachment).
    The more I look at it, the more I like it. For some reason it looks comfortable.

    What do you think.


    Pan+Prof.PNG


    The dashed lines in the profile represent a JoeBoat compliance gauge for her length.
     
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  15. sharpii2
    Joined: May 2004
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    Location: Michigan, USA

    sharpii2 Senior Member

    June progress report.

    I decided to set up the frames on the deck (which doubles as a construction jig.
    (see 1st attachment)
    I then installed the sides.
    (not shown)
    Once the sides were up, I started installing the chines.
    (see 2nd attachment)
    Lucky for me, none of my rather crude attemps at scarfing failed, but the keelson was rather iffy.
    All three of these longitudinals passed through the stern transom, but started at the bow transom. Their front ends had to be bevelled in order to fit against it. This was not as difficult as I thought it would be. Once the chines were screwed and glued in, I didn't have to worry about their scarf joints breaking. Not so for the keelson. It is only supported at four points: the bow transom, frame 46-, frame 90+, and the stern transom. Its bend, over these four points, was different than that of the chines. It was fuller at the stern. I considered using a Spanish windless to pull it down at the stern to make it fuller at the bow, but was afraid the extra stress on its scarf would be too much (I think the imperfect scarf, which is in the stern portion of the boat, is the reason the stern part of its curve is fuller). Deciding not to do this was to have consequences.
    Once all the glue had time to cure, it was time to fair the chines. I did this using a surform plane (a tool I added to my kit). I was relived to find that their curves pretty much matched one another.
    Next, it was time to instal the bottom panels, a job I dreaded. First, plywood is not like steel or aluminum. None of these panels was flat. All had verious curves and warps in them. Allso, I was quite aware that I I didn't have a straight run from side to sid, like I had planned (this was the start of the consequences). The bow panel was to go on first. Its front edge is to be GRP taped to the bottom of the bow transom. So I drilled holes in it and the bottom edge of the bow transom and lashed them together with some mason's twine. I would soon have to unlash them. This was because I decided to install all the panels with only screws at first to "train" them (and they needed a lot of "training"). All of the curved the opposite way I needed to bend them. I used a loosely set "C" clamp to hold the aft end of the first panel to the keelson.
    (see 3rd attachment).
    I knew there was to be some problem putting the screws in. Since nothing was flat or straight, I had to worry about the panel bunching up at some location. So the screws had to be put in, in a careful order. The method I chose was to start at the keelson and work my way out to each side and steadily work my way back. It worked. I didn't get anny significant bunching up on either of the chines or the keelson. Once the last screw was in, I carefully marked alignment points at the bottom edge of the transom. I also nmbered each screw location in the exact order in which its screw was put in. Next, I took the whole thing apart, put generous amount of PL Premium (r) glue on the chines and the keelson, Then put it back together. As you can see in the 3rd attachment, I ended up with a very shallow inverted "V" in the bow bottom. This I will have to live with.
    I used the same technique for the other two panels. I ended up with a slight "V" bottom at the stern (another one of those consequenses). The third panel gave me some trouble. there was some minor bunching up near the stern transom bu nothing terrible. The butt joint, hoever, turned out ugly. I ended up with about an 1/8th inch gap on the starboard side.
    After each panel was installed, I faired it to the side of the boat, using my sureform plane, before starting on the next one. This was to be a good decision, as I had to plane as much as 3/8th of an inch in some places.
    (see attachments 4 through 6).
    So this is what the final job looks like. You can see the profile drawing of the boat, along with a cardboard model, in the first one of these. In one of the other ones, you can see the blade of the rudder and the sailing rig in the background.

    Despite numerous mistakes and mis steps, it looks like I have a hull. With some effeort, I am confident that I can make it water tight.

    I relied on my lofting way too much. It was to be accurate only if I made no measurement mistake and if the lumber had the dimensions I expected it to have (it didn't). These two shortfalls made the lofting woefully inaccurate. I'm almost sorry I bothered in the first place. If i ever bjuild another one of these, or sell plans for one, I am going to use/recommend a wholelly different proceedure in building it. The lofting is only going to be used to determine the side frame heights. The frames themselves will be lofted. Then that's it. From then on, everything is going to be based on the side panels, which will first be cut out with no curves at all. The side-frames and the inner and outer bow and stern posts will then be used to dictate the bend of the chines. Once the chines are dry fitted, they will be traced onto the side panels. Then everything will be taken apart, and the finish cutting of the side panels will be based on that tracing. This is just one of several changes I would make in the building proceedure.
     

    Attached Files:

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