Small Cathedral Hull Boat. Ideas for designs.

Discussion in 'Boat Design' started by BadGoblin, May 3, 2010.

  1. BadGoblin
    Joined: May 2010
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    BadGoblin Junior Member

    Hi

    I have recently bought a small 2.6m x 1.2m cathedral hull boat made of fiberglass. I got it for next to nothing, the equavalent of +-$21.00. I want to fix it up and convert it into a small bass boat for dams. Its rated for 2hp - 10hp outboard.

    I was wondering if anyone has ideas on how to layout the boat. I was thinking of putting a full flat deck with 2 swivel seats. As this is my first boat I would appriciate any ideas, or tips.

    I've attached some pics to help with the ideas.
     

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  2. tom28571
    Joined: Dec 2001
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    tom28571 Senior Member

    This is a very small boat. Before you do anything expensive or time consuming, you should make a test of stability. Stick a sheet of plywood on it, set up a couple of folding lawn chairs, put it in the water somewhere and get a friend to sit with you. Imagine yourself hooking a nice fish and jumping up to land it while your friend also moves around to see. You may find that it just won't work the way you intend and avoid a lot of disappointment. It may work fine but it may be a death trap. I'm skeptical and lean toward the latter conclusion.
     
  3. messabout
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    messabout Senior Member

    The boat is too small for any mechanical power. Whoever rates it for two to ten horsepower is criminally insane. Tom has given you a valuable clue. I will give you another, even more valuable, suggestion. If you have a portable power saw, then use it to destroy that boat, if you do not have such a saw then borrow one and destroy the boat. It is a death trap as Tom suggests.

    Please forgive my straight forward commentary, I only wish to discourage unneccesary risk.
     
  4. BadGoblin
    Joined: May 2010
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    BadGoblin Junior Member

    Thanks for the info guys.

    I'm planning on doing just what Tom said. As soon as I get a chance to use my old man's van to move it. I was thinking about putting on an electric type sneaker motor. I'll report back after the stability test...
     
  5. Paul A
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    Paul A Junior Member

    Cover the existing boxes with 12 mm plywood lids, this is probably what they used to have. It's a planning hull and a 10 HP outboard will make it run well, don't be put off by the negative posts, you're the one that has to live with your decisions. It will be fun with a 10 HP on it and you should try it, but I'd try to find a 2 stroke to save weight on the stern.

    Don't over load this little boat with stuff. It doesn't need a casting deck that's 125 mm taller then the bottom of the boat, it doesn't need built in ice boxes or other devices, it's just a little boat that will blast along just fine if you keep it light weight, but will wallow like a tub if over loaded.
     
  6. tunnels

    tunnels Previous Member

    Wow what a little beasty thing !!
    Beef up the transom and make it strong , scuff out the inside with a grinder and reglass all the stuff thats inside the hull , 4 mm Ply over the tops ,glass both sides so it will last longer .
    Find a mean little 9.9 johnson or evinrude ,set up the motor to a good height ,do some measuring when you do the transom to make sure you can mount the motor at the right height , extend the tiller handle about a couple of feet with a piece of plastic pipe , then buy a really good life jacket and a pair of diving gloves , mount on the gunwhales each side a pair of good strong grab handles and you will be flying for sure !!.and i mean flying !!
    Great fun thats for sure if and when you have the guts to open the throttle full out !
    The 9.9 is the same outboard as the 15 hp but that would be my next choice !!
    Live life to the max !!
    id like to read about you in the flying pages !!:p :D
     
  7. tom28571
    Joined: Dec 2001
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    tom28571 Senior Member

    Nothing negative about my post Paul, just common boating sense. Read the original post and see what he wanted to do with adding two fishermen in chairs up high like a bass boat. No way this little tub will be safe with that rig no matter what the power. Of course lots of 8 foot boats can be fun and very fast with way more power than he planned but that was not the intent. Pay attention to what's said.
     
  8. Paul A
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    Paul A Junior Member

    A little harsh to a first time poster, was my point. And undeserved.
     
  9. BadGoblin
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    BadGoblin Junior Member

    Thanks for the support guys...

    I hope I didn't cause any issues. But I did ask for ideas and tips... As I said, Its my first boat and I have limited knowledge on boat building. I do however already own a kayak and a float tube and have been on many boats, deep sea and on the dam. I was obvioulsy not going to put a high deck, just one at water level with short swivel chairs.

    Attached is a pic of what I was kind of going for. But obviously with a lower deck.

    Anyway, any feedback is good feed back...

    Tunnels, I'll definately post pics up once its done.... Hope to fly too... lol. Apparently the cathedral hull gets on the plane quiet easily.
     

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  10. Wynand N
    Joined: Oct 2004
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    Wynand N Retired Steelboatbuilder

    BadGoblin.

    Follow the first two posters advice and get rid of that boat. Nice picture you have with the two pedestal chairs mounted. That will not happen, why? Try to stand up straight in that boat, or just sit and turn around and I guarantee you bad moments.
    I have a similar boat we build and sell as a one man boat with 30lb Minkota transom mount trolling motors and they do not sell well due to lack of stability.

    Why not contact me and I will sell you one of my bass boats I build to my own design (FishMaster range) called the "Bass Predator" The boat is 4.5m LOA and beam of 1.95m.
    It is a stripped bass boat hull with the upper casting decks, holding tanks etc etc removed that make boats expensive and impractical if you ask me, although it looks cool??
    Instead it has just three transverse bunks, tiller motor and the floor is flat - iow, an honest affordable fishing boat:cool:

    It is light weight - 155kg without motor - since it has no framing, stringers etc but solid poured in closed cell PU foam sandwiched between the hull and floor, making it immensely strong, solid and unsinkable.
    It is a stable boat as can be seen by the attached photos. Two big fellows can stand on the same side of boat with no stability problems. She goes like clappers with only a 15hp outboard and with that motor you do not need a skipper license or COF all any of the money making crap the new boating laws requires.

    BTW, cathedral hulls in my opinion are overrated on stabilty and cause a lot of drag/friction underway.

    Indien jy beland stel of verdere inligting benodig op enige bote, bel my op my Sel: 082-5377903
     

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  11. BadGoblin
    Joined: May 2010
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    BadGoblin Junior Member

    Nice boat Wynand... But i'm on a tight budget. How much you looking for for the boat? I doubt i'll be able to afford it right now. Send me an email with more details. Thanks
     
  12. messabout
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    messabout Senior Member

    Paul: you are quite correct about my harsh reply. BadGoblin I apologize for being such a curmudgeon.

    In the original post you envisioned two elevated fishing seats and no apparent reservation about engines up to 10 HP. That touched a very sensitive spot in my memory.

    Years ago I was sailing a small single handed boat in a very large lake. I had noticed a small, about ten foot, jon boat with a tall seat, a big motor and a fat man. He was fishing. Later, I was half a mile away when I saw him standing apparently to reel in a fish. The boat capsized and the unfortunate man went into the water. I sailed as fast as I could toward him. By the time I got to him it was too late. His very small boat was unsafe by any standards. Big man, big motor, ill concieved seating height, low freeboard, cost the man his life. That unpleasant memory is why my outburst was somewhat severe.

    Now let us explore the possibilites for your boat. Do as one of the others suggested. Clean out the interior, put thin decks on the boat that will enclose all but a small place for the driver. Put the 9.9 Johnson or Evinrude two stroke on the boat . You will drive the boat from a crouched or kneeling position. You will need some knee pads. The boat will go like a bat out of hell. Probably no more than 30 MPH but it will feel like 90 MPH. It will be indescribable fun. It will be dangerous in a turn, it may want to become airborne when running against the wind, or into a small chop or wake, it will pound your knees unmercifully but it might be worth enduring a little pain. How could I know all that stuff? Been there, done that with boats (plural) as small as the one you describe.

    Be very careful, have fun !
     
  13. tom28571
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    tom28571 Senior Member

    Heck Messabout, curmudgeons are people too.:D

    The truth is, those posts, yours and mine got the Goblins attention. That was a good thing. His original intent was a path to the same kind of disaster that you had to witness and some crumudgeonly ranting was in order. Any positive advice to go ahead with his project as stated would be criminal when you know the possible outcome can be fatal. I live in an area where deaths on fishing boats are all too common. One just last week that took several lives (I don't remember how many) in a capsized boat nearby.
     
  14. Paul A
    Joined: Apr 2010
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    Paul A Junior Member

    Just because you've had therapy over early boating activity in your lives, doesn't mean you should deprive the same from another, looking at the same path in boating life.

    He should be able to sit side ways on the boxes and tiller steer the boat. Yep, he'll get pounded, but that's the fun of it. In my area Tom (west central FL) we have several boating deaths a year. Some times people are unfairly taken, but I've noticed that more often then not, these are people everyone else admits were aiming directly at challenging mortality in most of their ventures. Bungee jumper dies in PWC incident, local sky diver drives boat into bridge, ex-navy seal breaks neck attempting 60 MPH turn in overpowered Jon boat, etc. OBGYN's drive Volvo wagons, Bubba and JimBob drive 500 HP Pinto's. These are gross exaggerations, but all too often true. Much more often then not excessive beer is in the mix.
     

  15. DocScience
    Joined: Apr 2010
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    Location: Sydney, Nova Scotia, Canada

    DocScience Wishful builder

    What I would do

    If other tests did not work out well, this is what I would do.
    It is probably not the best idea, but I would like to see what happens.

    I would securely attach a pontoon on each side with some type of bar across.
    If the fiberglass boat can be put in usable shape easily, I would try any type of square or round pontoons.
     

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