Transom space filling

Discussion in 'Boatbuilding' started by billy241072, Sep 29, 2010.

  1. billy241072
    Joined: May 2010
    Posts: 8
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: South Africa

    billy241072 Junior Member

    Which material can I use to fill gaps between the new transom and the hull?
     
  2. CDK
    Joined: Aug 2007
    Posts: 3,324
    Likes: 145, Points: 63, Legacy Rep: 1819
    Location: Adriatic sea

    CDK retired engineer

    It might help to supply some information first. There are clever people on this forum, quite willing to help, but no psychics.
     
  3. billy241072
    Joined: May 2010
    Posts: 8
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: South Africa

    billy241072 Junior Member

    You are welcome to keep your sarcasm to yourself.Back to the point.My hull has a slight curve at the transom.I managed to curve the wood but not perfectly flush with the hull.I want to know what method I should use to fill the voids where the wood is not touching the hull.
     
  4. daiquiri
    Joined: May 2004
    Posts: 5,372
    Likes: 239, Points: 73, Legacy Rep: 3380
    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    Any pictures, please?

    And:
    You better accept a bit of humor in the replies, or you'll have a hard time reading this forum. ;)
     
    1 person likes this.
  5. CDK
    Joined: Aug 2007
    Posts: 3,324
    Likes: 145, Points: 63, Legacy Rep: 1819
    Location: Adriatic sea

    CDK retired engineer

    Totally uncalled for.
    How are we to know your boat/transom is made from timber or plywood and not from ferro-cement, glassfiber etc?
     
  6. WickedGood

    WickedGood Guest

    Your best bet would be to get a case of this and squeeze it into any voids you may have.

    The Pesce' little fishis will follow you like a Red Bone Hound Dawg follows Coons.




    [​IMG]


    Dont forget to Post Feedback for me and Vote Positive Rep Points just to drive Apex1 Nuts!
     
    1 person likes this.
  7. daiquiri
    Joined: May 2004
    Posts: 5,372
    Likes: 239, Points: 73, Legacy Rep: 3380
    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    :D :D
     
  8. daiquiri
    Joined: May 2004
    Posts: 5,372
    Likes: 239, Points: 73, Legacy Rep: 3380
    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    In absence of further info, my first thought is that you can make a filler by mixing epoxy with colloidal silica (West System 406, for example). Add silica to epoxy (and mix them well) until you get a dense paste, similar to mayonese or butter at room temperature. Then fill the voids with the paste.
     
  9. mydauphin
    Joined: Apr 2007
    Posts: 2,166
    Likes: 52, Points: 48, Legacy Rep: 575
    Location: Florida

    mydauphin Senior Member

    Sarcastically.... :p Your transom should be attached to your hull.. ha ha.

    Apart from that the West system with high density filler as mentioned is your best bet.
     
  10. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 470, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Ideally, the transom core (I'm assuming) should be married to the hull shell skin and to a hull liner if one is used in you application. This marriage should be stronger then the weakest portion of the assembly, which typically is the core.

    For a wood to 'glass bond, use approximately 50% silica and 50% milled fibers to glue the core to the hull shell. This mixture should be fairly thick or it'll just run to the bottom, likely into the bilge. The consistency should be that of peanut butter, so that when removing a putty knife from this mixture any peaks that result, remain and don't sag back into the mix. This stiff mixture is applied first with a notched trowel, who's depth should be deeper then the largest gap. Then any "ooze out" is filleted to the core's edges, making a radius. Complete the fillet around the edge of the core.

    Next the core is "tabbed" to the hull shell. Depending on how thick the hull shell is, what type of boat, if an outboard will be involved, if back stays will be involved. On a small runabout transom with a 40 HP outboard, the tabbing would be 3 layers of 12 ounce biax tape (6" or wider if using fabric). This tabbing ties the core to the hull shell and helps transmit load to the hull shell, without localized strains. The tabbing should extend out onto the hull shell at least 6", preferably more, in over lapping layers. The exact amount again is dependent on what you have and what is going to be attached to it.

    Lastly is bonding the liner to the core, which is similar to the hull shell bond, except you don't have to tab anything. Just mix up a stiff mixture and using a notched trowel wedge, brace, temporary screw the liner into position until the epoxy cures.
     
  11. daiquiri
    Joined: May 2004
    Posts: 5,372
    Likes: 239, Points: 73, Legacy Rep: 3380
    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    PAR, I understand that billy241072 is talking about a wooden, not a GRP/foam, boat... :?:
     
  12. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 470, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Okay, but that's not what I've gathered from his posts on this thread. If he could straighten up this issue it would be helpful, as my advise for a wood boat will be different, though he now may be chased off the board by the "sarcasm".
     
  13. daiquiri
    Joined: May 2004
    Posts: 5,372
    Likes: 239, Points: 73, Legacy Rep: 3380
    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    I hope not. A little bit of humor is an essential part of this forum, imho.
    Besides that, if a small dose of sarcasm is enough to put a person on the run, I wonder what would he/her do when faced to the real difficulties of the life... ;)
    Cheers!
     
  14. alan white
    Joined: Mar 2007
    Posts: 3,731
    Likes: 121, Points: 0, Legacy Rep: 1404
    Location: maine

    alan white Senior Member

    It happens a lot that a question has 10 words and the answers have hundreds of words, most of which are wasted because of lack of information on the part of the asker.
    Why can't some new posters go to a bit more trouble and actually provide real information like the boat's material? Don't they understand that people are sitting down and committing a lot of their valuable time in attempting to answer those questions?
    Billy, CDK was entirely justified in what he said. Sarcasm is a lot better than outright dismissal, which is what the question really deserved.
    Sure, you want sophisticated answers to simple questions. Thanks to the generosity of a couple of posters, you now know more than you did. More than was warranted by the seven seconds you spent typing the question, I think.
     

  15. billy241072
    Joined: May 2010
    Posts: 8
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: South Africa

    billy241072 Junior Member

    Ok I apologise for overreacting a bit.I had a sensitive moment there.The boat is a runabout fibreglass hull and I'm using 2 sheets of marine ply to build the transom.It will carry a 50Hp Mercury from the 80's.The sheets of ply when fitted touches the centre of the hull and then gradually the spacing increases to a max of 1inch,because the hull has a curve in it.I need to fill this 1 inch gap.Txs Ladies.
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.