Seeking Assistance, Again

Discussion in 'Multihulls' started by BobBill, Nov 21, 2022.

  1. BobBill
    Joined: Oct 2009
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    Location: Minnesotan wakes up daily, in SE MN, a good start,

    BobBill Senior Member

    As some know am improving on current project
    Am looking for foam hull sides to make light. boat hull…figure to make hot-wire cutter and use deck and stem as cutter guides to cut pink or blue foam, to shape, to avoid sanding mess….assymetrical ama (hull), like Hobie 16, so starb'd side is more or less flat, know to alleviate center board need and has web or stiff material. Have old 16 hull to use.

    Waterproof for loa to which foam is glued…heard epoxy is too hard and was advised Ato use softer adhesive like Gorillla Glue

    Y’all are very knowledgeable…and helped me lots in past…avatar is rig and last (pre-C-19) I sailed rig was perfect…but need to lighten Ama outrigger and still carry crew +, which full foam hull can do...Y'all saved me from weak Hobbie hull and I added stays, following your admonitions as weak hull.


    Plan to use 4 6061s fastened to loa web to hook ama hull to outrigger beams/or amas. Note, boat is NOT a shunter, by choice, (Has rudder to tack.)
  2. bajansailor
    Joined: Oct 2007
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    Location: Barbados

    bajansailor Marine Surveyor

    Hi Bob,
    You have simply repeated your previous thread posted on Saturday, as per the link below.
    Need some Advice

    One reason as to why you have not received any replies so far is that your post is not very clear - I am a bit baffled as to what you are after.
    Are you going to use an old Hobie 16 hull as a male mould to wrap the foam around?
    I presume that you will then glass it?
    What does 'loa' stand for in this context - I presume not 'length overall'?
    Can you post any sketches or drawings of what you want to build?

    Are these 6061 aluminium beams going to be tubular, square section, I beams or channel sections?
  3. fallguy
    Joined: Dec 2016
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    Location: usa

    fallguy Senior Member

    Pink or blue foams are insufficient as the off the shelf versions lack sufficient shear or compressibibility.

    They will delaminate from bumping a dock or the bottom or under a foot planted unevenly. After an original delam event, like a rock, hydraulics does the rest.

    I have used pink for amas for canoe outriggers, but would never consider for hulls.

    There are MANY! great plans for these types of boats and plywood is a fine option for hard chines. For round hulls; things get a bit more complex.

    If you intend on building a solid ama, then pink foam is okay, but abrading it deeply and ordering a higher compressibility/shear version is wise.

    consider this a starting point

    Also, please use good editing. Posts that are hard to decipher do not get lots of replies.
    bajansailor likes this.

  4. fallguy
    Joined: Dec 2016
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    Location: usa

    fallguy Senior Member

    PS...I am in minnesota
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