Am I crazy? Extending boat's length

Discussion in 'Metal Boat Building' started by rendon_6, Jan 16, 2012.

  1. rendon_6
    Joined: Jan 2012
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    rendon_6 New Member

    Has anyone ever cut the back end off their boat and added a couple feet in than welded it back together? Or would that be to crazy. I have a 12 ft flat bottom and I wanna 16 ft. So I would have to add 4 foot in and than i would want to add pods to the back.

    What do you all think or am I just crazy?

    Here it is now

    Here is what i am thinking

    Plan A
    I would remove the back seat and cut off the last 1 1/2" to 2" than weld than weld the 4 foot section in, add a few supports and re install the seat in.

    Plan B
    would be to cut the the boat about 4 foot from the back just in front of the rear seat than weld the section in and add supports.

    Would I have to put the square chimes in the bottom of the piece that i added in on both plans i thought i might be able to get away from the chimes if i did plan a and just had the last 4 foot smooth.

    than i would add a deck to the front with a door to store things in and pods to the back.

    What you all think
  2. tunnels

    tunnels Previous Member

    Been there done that with a glass boat a few times

    We are all a little crazy !! hardest part id finding the right place to chop it !! Added a metre into the last boat i cut and made it into a really nice boat . was a short fat thing and a terrible sea boat!! Uncomfortable to ride in !bounced around and flopped in a harbour chop .The guy bust wanted a couple of feet but talked him into a metre and changed the motor from a really old omc 85hp to a brand new 90 merc lighter motor , more power and the extra length change the whole thing . more room inside , no more buncing from one chop to the next , and flop went completely !
    An Aluminium boat shouldnt be a issue !just make sure you cut it nicely and straight lap the joins rear inside each join . Riviting or welding the 2 joins ?? string line the keel and make sure you get the line 100% straight when you join it again . The hardest thing is doing the first cut !,Is all done in minutes and you wonder what all the fuss was about . :)
    Plan B would be my option and make the cut half way between the frames so have room to work and be sure . Have you talked with the boat manufacturer and see if you could get a section of the hull pressing with all the shapes in it already or even find a damaged boat the same sort and hull shape
    Me being a glass person i would make a mould off the existing hull and make a glass section witha flange each end then rivit and use West flexable Epoxy the joins with 30 mm over lap each way !
  3. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    They extend ships, so no, you are not crazy.
  4. Ike
    Joined: Apr 2006
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    Ike Senior Member

    Frankly I would just buy a bigger boat.
  5. Easy Rider
    Joined: Oct 2009
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    Easy Rider Senior Member

    I'd like to extend most of the boats I own. Two of the Alaska State ferries got extended many years ago and 100% successful as far as I know.

    Easy Rider
  6. michael pierzga
    Joined: Dec 2008
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    michael pierzga Senior Member

    Before you chop and stretch your jon boat, MAKE SURE THAT YOUR RIG WILL FIT YOUR CAR

    Very very important.

    Attached Files:

    1 person likes this.
  7. tunnels

    tunnels Previous Member

    That picture made my day !! Fantastic !!well done !:D
  8. cor
    Joined: May 2008
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    cor Senior Member

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  9. johneck
    Joined: Nov 2011
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    johneck Senior Member

    Sounds crazy to me. While completely possible, the benefit is probably not worth the effort. They make these alum boats in many sizes and shapes; buy one the right size.

  10. The Loftsman
    Joined: Jun 2010
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    The Loftsman The Loftsman

    Yes you can but be careful and extend it amidships for'd and aft perhaps a frame space or so each side of midships, there have been disasters at sea put down to this not being done correctly and has cost life.

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