Oar Locks & Seats

Discussion in 'Boat Design' started by Maine Rookie, Aug 23, 2005.

  1. Maine Rookie
    Joined: Aug 2005
    Posts: 2
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Gray, ME

    Maine Rookie New Member

    I am strictly a rank amateur builing a plywood boat in my garage with my son over the summer. I have come close to converting the entire thing into firewood twice now, but I am hanging in there! I am building a 13' fairly flat bottomed boat with a flat bow that narrows down to 20". The plans do not call for any oar locks, and I don't like the seat postions they call for. The boat will mostly be rowed in local ponds or tidal back waters. My question for anyone is how do you figure out the best placement of oar locks in relation to the seat? Are there any guidelines? And, do the oarlocks get installed at the widest point of the boat? And, are there any guidelines about where to place seats in relation to the length of the boat.

    Anything anyone can offer will be appreciated

  2. marshmat
    Joined: Apr 2005
    Posts: 4,127
    Likes: 148, Points: 63, Legacy Rep: 2043
    Location: Ontario

    marshmat Senior Member

    Oarlocks are usually near the point of maximum beam. For a rowboat, the seat should be more or less right above the centre of buoyancy. If the boat's designed to carry a motor it could be a bit of a pig to row though. Sometimes in little boats like this the seats are structural and you have to be careful if you move them to make sure you keep the strength that they would give. Work out the seat location on paper first, and if it's not where it was originally meant to be then beef up the structure there so that the boat will still be rigid. Once the seat's in and everything's nearly finished, put your new yacht on blocks and boards, sit in it, and have friends hold the oars against the gunwales. Try a rowing motion, and have your friends move the unattached oars until one is in a comfortable spot. Put the oarlocks there. If more than one person will row the boat, try putting 3 or 4 pairs of oarlocks in a row on each side so shorter and taller people can both be comfortable.
  3. thlamers
    Joined: Jan 2003
    Posts: 1
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Yellow Springs, Oh

    thlamers New Member

    Oarlocks and Seats

    This is a good question and the best answer I have seen is to allow for variation in the placement of the oarsperson and oarlocks. This way you can adjust for number of persons in the boat. For single occupant the advice already given is ideal. If for a rower and a passenger then the boat can be imbalanced and the oarlocks and rower's seat should be adjusted to make the boat float in trim.

    On our tiny inflatable the center rower's seat can be locked either fore or aft and the oarlocks easily adjust fore and aft (could have two sets of oarlocks). The best solution for a larger skiff type boat is a central fore and aft seat and two or more sets of oarlocks. Done correclty this still allows ideal geometry and also gives the option of rowing facing forward.

    Tom LaMers
  4. Maine Rookie
    Joined: Aug 2005
    Posts: 2
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Gray, ME

    Maine Rookie New Member


    Thanks for the info. That question came up last summer. I sat in different boats and looked at a few more and ended up putting the oar locks about the same distance towards the stern as my knees.

    Believe it or not, I have not gotten the boat into the water yet, but am finishing the exterior. Hope to put the first coat of sealer on next week.

  5. Gilbert
    Joined: Aug 2004
    Posts: 525
    Likes: 5, Points: 28, Legacy Rep: 28
    Location: Cathlamet, WA

    Gilbert Senior Member

    I have found that about 9 inches aft of the aft edge of the rowing thwart (seat) is about right. You should be alright if it is within an inch or so of this.
  6. sal's Dad
    Joined: Apr 2005
    Posts: 109
    Likes: 7, Points: 0, Legacy Rep: 85
    Location: New England

    sal's Dad Atkin/Bolger fan

    > about 9 inches aft of the aft edge of the rowing thwart

    I figure on 10" - this will vary a bit with the precise geometry - beam, height of lock, etc. If you put in temporary sockets at 8, 10, 12, you will find out pretty quickly.

    Of course this all assumes you have proper length oars! Experts differ on what is the right length (1/2 beam X 3 + 6" , or 2 x beam.... ) but in any event I have rarely found anything less than 7' satisfactory in any boat.

    Sal's Dad

  7. hoytedow
    Joined: Sep 2009
    Posts: 5,718
    Likes: 316, Points: 93, Legacy Rep: 2489
    Location: North of Cuba

    hoytedow I'm not a cat.

    Is it better to pin the oar in the oarlock or is there a better way to keep the oar from slipping out of position?
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.