Rowing catamaran

Discussion in 'Boat Design' started by Lloyd Le Blanc, Nov 2, 2023.

  1. Lloyd Le Blanc
    Joined: Nov 2023
    Posts: 6
    Likes: 2, Points: 3
    Location: Guelph, Ontario, Canada

    Lloyd Le Blanc Junior Member

    Hello,

    I am looking for plans, and measurements to build pontoons for a 15 /16 rowing catamaran with moving riggers.
    Thanks, Lloyd
     
  2. BlueBell
    Joined: May 2017
    Posts: 2,649
    Likes: 941, Points: 113
    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

    What's a 15/16 rowing catamaran?

    How many rowers?

    What purpose will the cat serve?

    Fixed seat, moving riggers?
     
  3. Lloyd Le Blanc
    Joined: Nov 2023
    Posts: 6
    Likes: 2, Points: 3
    Location: Guelph, Ontario, Canada

    Lloyd Le Blanc Junior Member

  4. BlueBell
    Joined: May 2017
    Posts: 2,649
    Likes: 941, Points: 113
    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

    Contact ROCAT, they not only have plans, they make them!
     
  5. Lloyd Le Blanc
    Joined: Nov 2023
    Posts: 6
    Likes: 2, Points: 3
    Location: Guelph, Ontario, Canada

    Lloyd Le Blanc Junior Member

    Hello,

    Well, I have been in contact and they do not have plans and are no longer making the.
    Thanks, Lloyd
     
  6. bajansailor
    Joined: Oct 2007
    Posts: 3,559
    Likes: 1,531, Points: 113, Legacy Rep: 37
    Location: Barbados

    bajansailor Marine Surveyor

    That Rocat really is an amazing design - one would think that it would not be possible to 're-invent the wheel' (or the sliding seat arrangement in this case) when it comes to rowing - but they have, very effectively.
    And it makes a lot of sense - instead of having fixed oarlocks on outriggers with the seat (complete with the weight of the rower) sliding to and fro, creating a lot of momentum, the seat stays fixed, and the outriggers are on hinges, allowing them to swing fore and aft.

    I saved a copy of the video that was posted on the site, showing how it all works, and I wanted to post it here - but it is too large (15 MB).
    However I found the same video on Youtube - here is a link :


    @Lloyd Le Blanc maybe you could use a pair of Hobie cat hulls (either the Wave or the Getaway) for your Rocat?
    Find your Catamaran | Hobie https://www.hobie.com/sail/
    It should not be too difficult to find a pair for not a lot of $$'s.
    OK, the hull form for the Rocat is probably much more optimised for rowing than the Hobie hulls, but I think the Hobie cat hulls would still give a good turn of speed, and would be much cheaper in the long run.

    And it should be possible to copy the sliding outrigger system (with a bit of trial and error along the way) from the videos on line and the basic info available?
     
  7. Lloyd Le Blanc
    Joined: Nov 2023
    Posts: 6
    Likes: 2, Points: 3
    Location: Guelph, Ontario, Canada

    Lloyd Le Blanc Junior Member

    Hello, I have rowed a sliding rigger boat and they are really great. The International Rowing Association has banned them in competition as they were faster than conventional riggers. I have looked at using Hobbie outriggers however they are too heavy. I have refurbished over 25 single rowing sculls and have built two. I will be building two "stitch and glue" outriggers and have been working on the design of the sliding rigger. Thanks, Lloyd
     
    bajansailor likes this.
  8. Skip Johnson
    Joined: Feb 2021
    Posts: 30
    Likes: 19, Points: 8
    Location: Lake Tenkiller, Ok, usa

    Skip Johnson Junior Member

    Interesting, probably a big advantage in having less movement of CG in relation to CB.

    FWIW last year I had a client interested in building a human powered catamaran to challenge the current Guinness distance travelled in 24 hours in a human powered craft. He was well versed in pedal powered paddle race craft. I was hesitant to do the deal citing the fact that a catamaran has a built in 40 % penalty in wetted surface over a similar monohull. But in running the numbers in Michlet/Godzilla it turns out that a catamaran will be competitive with monohull or proa configuration as regards total drag (friction and wave) in the speed range required to be competitive in the 24 hour challenge.
     
  9. Robert Biegler
    Joined: Jun 2017
    Posts: 161
    Likes: 80, Points: 38
    Location: Trondheim

    Robert Biegler Senior Member

    You would also get a decent hull shape from the Expandacraft kit, and they have mounted Rantilla's Frontrower on one:


    The Frontrower should (meaning I am not speaking from personal experience) give you the advantages of the sliding rigger, you can see where you are going, and you can row with feet alone or hands alone, in case of injury: Forward facing rowing for canoes, rowboats https://www.frontrower.com/

    The amas of a Hobie Tandem Island or one of the Windrider trimarans also look quite suitable as hulls for a single rowing catamaran. However, spare parts tend to come with a large markup. Decades ago, someone added up the cost of all the spares from which you could assemble a Hobie 14, and it turned out to be about twice the price of the boat as a whole.
     
  10. BlueBell
    Joined: May 2017
    Posts: 2,649
    Likes: 941, Points: 113
    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

    Lloyd,

    If they made them, then they had plans.
    Did you offer them money for a set of plans?
    Have you looked for a used one?
    Even damaged you could get the measurements you seek.
    Failing all those options, this is not a difficult design to recreate, no?
     
  11. Lloyd Le Blanc
    Joined: Nov 2023
    Posts: 6
    Likes: 2, Points: 3
    Location: Guelph, Ontario, Canada

    Lloyd Le Blanc Junior Member

    Hello,I have been rowing for over 30 years and I retirement have refinished 25 single sculls and built two.I have no problem rowing backwards and in the last couple of years have used a Bluetooth camera with a tablet to see where I am going and it works quite well. I intend on building my own outriggers and working on the sliding rigger.Thanks
     
  12. Rumars
    Joined: Mar 2013
    Posts: 1,777
    Likes: 1,089, Points: 113, Legacy Rep: 39
    Location: Germany

    Rumars Senior Member

    BlueBell likes this.
  13. BlueBell
    Joined: May 2017
    Posts: 2,649
    Likes: 941, Points: 113
    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

  14. kapnD
    Joined: Jan 2003
    Posts: 1,293
    Likes: 408, Points: 83, Legacy Rep: 40
    Location: hawaii, usa

    kapnD Senior Member

    Darn, I really wanted to see the guy catch a wave.
    That should be exciting going backwards!
     

  15. BlueBell
    Joined: May 2017
    Posts: 2,649
    Likes: 941, Points: 113
    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

    Ya, me too!

    I'd be a lot more comfortable in those conditions with a centre boat pod (capsule) wrapped around me,
    but that's added weight which is not helpful.

    Lloyd, I can see why you want those pontoon designs but I feel confident you could recreate them.
     
    bajansailor likes this.
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.