Please critique my open transom skiff design

Discussion in 'Boat Design' started by markgoespop, May 24, 2018.

  1. markgoespop
    Joined: Jul 2017
    Posts: 12
    Likes: 0, Points: 1
    Location: UK

    markgoespop Junior Member

    I have been daydreaming of building my second boat. It is supposed to accommodate 2 offset fixed-seat rowers in a 14' package, while being fairly efficient, stable and unsinkable even in some chop. To this end, it will have an open transom with a full deck, sloped from the lowest point in the transom to middle-height at the bow. I took the 9 degree deadrise and 80 degree flare from sea kayak design advice.

    I've come up with the following hull:

    The bow is very low intentionally, to fit in my car when nested -- I have a plan for a strong way of joining the 2 halves, and I will have a solid seat-back extend upwards about half a metre back from the bow to discourage water from entering over the top, rather like the raised gunwales on a shell.

    I've checked buoyancy, and it looks good for 250kgs, while loading to keep the bottom of the transom at the waterline and half burying the bow. The prismatic coefficient is 0.65ish, if I am using the software correctly.

    Does this look like a reasonable design? Are there any changes that would improve it?

    Here is a FREE!ship file, if you want to play with it:

  2. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 497, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    With a competent skipper, enough sail area, you should be able to get her up and scooting pretty good. You'll be hiking fairly regularly and she'll likely want to sail at 12 degrees of heel or more the decrease wetted area. Her Cp offers the potential to turn a fair speed too. Looks easy to plank up and I'd move the max belly of the reverse sheer aft a bit, where you'll likely need it when hiked out. As a pulling craft, she'll do well, though with her Cp as high as it is, you'll leave quite a bit on the table in speed potential, except when two young and healthy rowers are pulling hard. This isn't a bad compromise, as too low a Cp is more of a determinant than too high. You could go a lot faster with a sail on her and it doesn't even have to be a lot of area, given her wetted surface.
  3. Dolfiman
    Joined: Aug 2017
    Posts: 1,497
    Likes: 660, Points: 113
    Location: France

    Dolfiman Senior Member

  4. markgoespop
    Joined: Jul 2017
    Posts: 12
    Likes: 0, Points: 1
    Location: UK

    markgoespop Junior Member

    @PAR: Thanks for the opinion. I do intend to move the belly of the reverse sheer aft a bit, but not for sailing: I would like to try an offset fixed-seat sweep rowing setup without big outriggers, like a really narrow 2 person Cornish gig or Aussie surfboat.

    @Dolfiman: Yes, they are similar, especially the Yole. I also saw the Driade 444, the Clovelly scull, the Solo Bois MGM and FISA C1X/C2X boats.
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.