Alternative ways to build a seat

Discussion in 'Fiberglass and Composite Boat Building' started by Southern Cross, Feb 20, 2014.

  1. Southern Cross
    Joined: Mar 2013
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    Location: So. CA

    Southern Cross Senior Member

    A friend of mine wants to cut out the existing seats in the cockpit of his racing sailboat and raise the floor several inches so that there will be more room for the crew to maneuver. The new piece is a very basic shape with a cored floor and a wall on each side (similar to what is shown in the photograph). The existing wall of the seat is not cored - just glass.

    I thought since the shape is so basic you could make a mold from plywood, lay down glass, core, then glass then glass in the new piece. The whole deck will get a a few coats of gelcoat later.

    Does this sound reasonable? Any other suggestions?
     

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  2. Southern Cross
    Joined: Mar 2013
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    Southern Cross Senior Member

    These are the seats he wants to cut out. The traveler will be lowered to the floor and with the new raised floor, it will be easy to sit on the rail and steer.
     

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  3. Petros
    Joined: Oct 2007
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    Petros Senior Member

    It can be done. you might weaken the hull, the foot well stiffens the seating area. It might be wise to contact the designer, if he is still around, to see if there are any structural considerations with your proposed change. If not available than find a competent NA that is familiar with this boat.

    Would making this change alter it enough to change the rating rules for this hull? or is the type of sailing you plan on doing this would not matter?
     
  4. Southern Cross
    Joined: Mar 2013
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    Southern Cross Senior Member

    Hi Petros,

    The designer is long dead and no, the owner doesn't care about the rating. It's been done before but we have no way of contacting those owners. We would reinforce the new seat as much as necessary. The shop that was doing other modifications is taking too long. So he's looking into ways of getting it done himself.

    Just wondering if a mold is the easiest way to go or is there another way?
     
  5. Baltic Bandit

    Baltic Bandit Previous Member

    Shouldn't be any diff to the rating as the net amount of glass will be the same. BUT there are some serious structural issues to consider. essentially the footwell acts as two beams of FG running the length of the cockpit.
    .
    take that out and in the highest load part of the boat you will now have a lot of flex.
     
  6. Southern Cross
    Joined: Mar 2013
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    Location: So. CA

    Southern Cross Senior Member

    Hey BB,

    Boy, you get around. How is Paris these days? I used to live on Rue St. Louis and I remember the best Crepe shop there.

    The footwell will be raised slightly but widened from .561m to 1.839m. The only parts being removed are the actual seats. We would support the footwell as in the current arrangement but also add other support along the walls to the hull where none exists now. What do you think?

    This is what it looks like currently...
     

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  7. Southern Cross
    Joined: Mar 2013
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    Location: So. CA

    Southern Cross Senior Member

    Did I mention that he wants to keep the transom as is?

    Here is a boat that had the same thing done but without raising the floor.
     

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  8. Baltic Bandit

    Baltic Bandit Previous Member

    We finally got a sunny and somewhat warm day. There's been a fvckall nasty grippe going around that has taken me 6 weeks to kick (still have a bit of a cough).

    the stern is fine. The issue is that the Seats with the vertical of the footwell essentially form a "U-channel"... and as we know Uchannels are added to things to increase rigidity.

    So he can easily do the conversion, but he needs to add some sort of vertical flange below decks to maintain the stiffness of the boat. I assume he's got a motor down below there which makes it hard to do. So perhaps he should consider running end to end CF "Uchannels" (strips of foam then laminated over with CF) down the length of the new floor. These could then act as toeholds in the new wider cockpit. do 4 of them and you might be near the stiffness of what you are replacing.. But otherwise the backstay and mainsheet are going to start bending the stern upwards
     
  9. Southern Cross
    Joined: Mar 2013
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    Location: So. CA

    Southern Cross Senior Member

    H1N1 virus going around here. Nasty stuff.

    Toe rails are a good idea. I've seen those on other sport boats.

    Surprised at you BB not recognizing an Olson 30. I'll give it to you since you've been sick. No motor. Outboard transom hung. Thanks for the advice.
     

  10. Baltic Bandit

    Baltic Bandit Previous Member

    I thought it might be an Olson 30, but from Down Under i'm never sure so I'm hesitant. Or is this So Cal? I agree the narrow box in an O30 cockpit is a PITA. So then since there is no inboard on board, I'd go a combo of toerails and down below I would take two sheets of marine grade 3/8ths and connect the floor of the cockpit to the bottom of the boat with nice flanged and bogged FG tape. Then paint the whole thing with white marine enamel .

    that way you get a really solid back and and a really nice cock pit. but with the wider cockpit at least two torails will be needed. but i'd first put them where I thought they needed to be with Silicone glue (yeah it will sheer off eventually but you ain't gonna kkeep it there that long). and move them around until they are in the right place. then bed them with RTV 5200
     
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