Raising the gunnel

Discussion in 'Fiberglass and Composite Boat Building' started by fealeranger, Dec 14, 2013.

  1. fealeranger
    Joined: Dec 2013
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    fealeranger Junior Member

    Repair and raising the gunnel

    Hi everybody,
    I'm new to the forum but am very interested in boats and their construction. I hope to attempt to make my own Dory style boat over the next few years but for now I have a few things I would like other opinion on. I got this Dory/Gandelow style boat that has a few dents and scrapes for fixing. I am going to attempt to do them myself but I am new to glass and gel coat so I want to see if you guys think it is a good idea to try myself or get a more experienced guy aboard to do this. Some pictures here to give you an idea what I'm facing. This is the boat
    http://i943.photobucket.com/albums/ad275/rmck79/Fishing/IMG_2032.jpg
    This is the damage I need to repair.
    http://i943.photobucket.com/albums/ad275/rmck79/IMG_3724.jpg
    http://i943.photobucket.com/albums/ad275/rmck79/IMG_3722.jpg
    http://i943.photobucket.com/albums/ad275/rmck79/IMG_3721.jpg
    I am trying to figure out if I will need to glass these or will I just need to repair the gel coat. I am also hoping somebody can attempt to guess what colour this boat is:confused:? Eventually i will need to raise the gunnels by 6-8cm as the oars are too low and want to know is this a big job? Any coments are welcome and helpful. Cheers.
     
    Last edited: Dec 14, 2013
  2. fealeranger
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    fealeranger Junior Member

    Anybody?
     
  3. SamSam
    Joined: Feb 2005
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    SamSam Senior Member

    Welcome

    That looks to be just gelcoat repair that's needed. Do it yourself so then when other dings happen, you know how to fix them.

    It's hard to tell the color... some shade of grey? Take some white gel and mix in a little dark grey or a tiny bit of black. Mix it to match what you have, it won't change color as it hardens.

    If you raise the gunnels, you increase the windage, which might be a problem. Do you need them higher to keep out the water? How come the two oarlocks are off set from one another?

    Merry Christmas
     
  4. PAR
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    PAR Yacht Designer/Builder

    Welcome to the forum.

    Raising the gunnel is a pretty complex job for a novice and not at all necessary to fix the lock oar lock position. The usual route for this issue is to just raise the lock pads, which appears to have been done to some degree already. Though adding another few inches to this height might look a little weird, it'll be the easy and quick way to get a comfortable locks where you want them.

    To add another strake to the gunnel will mean another sheer clamp, extending the frames and other supports, making the transom taller, moving or installing another breasthook, etc. This is a much more involved job than it seems on the surface, compared to just making taller lock pads, which should be longer, along the rail then they show in the picture.
     
  5. fealeranger
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    fealeranger Junior Member

    Thanks for the info guys. The oar locks are staggered as the oars are worked by two seperate persons when in use. The oars are long oars about 13ft, I think they are called sweeps. We had to raise the oar lock temporairly 2 years ago in a hurry as you can see from the picture:eek:. I am hoping to get some time between now and June to do a better more permenant job on these oar locks but I need to try and find some examples so I can decide what I need to do. From what is in the above post Raising the gunnel is out the window. What I will need to do is put rib style cleats under the boat to help keep it straight and help protect the floor. I will probably try to glass some oar locks onto the gunnel. I am new to all this but I am very interested in attempting to glass and gel coat myself. I might torment all you guy's in the next few months with silly questions so my apologies in advance. First I need to go hunting for materials and figure out how to prepare the floor and what to use as cleats to glass on to the bottom.
     
  6. Tungsten
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    Tungsten Senior Member

    That's a neat looking boat,just a thought but 13' oars must be hard to Handel.Could you not switch too 2 oars man with 2 sets of normal oar locks?You could then use much shorter oars that don't need to be so high.
     
  7. fealeranger
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    fealeranger Junior Member

    2 oars man with 2 sets of normal oar locks would not be adequate for our purpose. The long oars are perfect to row the boat against the tide during fishing. It is a fabulous boat on the water, I just need to put some sort of keel under it to help keep maintain a straight line. I wonder would it be possible to glass on something like 3 or 4 semi circle lengths of wood along the base like cleats?
     
  8. PAR
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    PAR Yacht Designer/Builder

    A skeg (what you're trying to describe as semi circle thingies) will work, but you only need one, for good tracking. Two would protect the bottom better and these would be about 2" (50 mm) tall, running the full length of the bottom, mounted about 1/6th of the max beam, (measured in from each side), parallel to the centerline. Taper down the forward end a bit so you can bounce over stuff easily. Ideally, these are hardwood and sacrificial in nature. They're intended to get beat up, then replaced as required. If you use a single one on the centerline instead of two, make it 3" (75 mm) tall.
     
  9. SukiSolo
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    SukiSolo Senior Member

    Following on from PAR maybe a single centreline skeg and two smaller bilge keels or side skegs. This should both give the straight line ability plus the protection. If you went this route, the side skegs could be a lot shorter and still give enough protection. Try and use the crease of the floor to the sides as a strong point. Avoid just having a skeg on the 'flat floor' only, so ensure it goes right to the ends with a central skeg.

    You should find this type of protection on many existing boats, both wooden and fibreglass. It is also possible to reinforce the timber skegs with brass or aluminium bands (keelbands) screwed onto them. If so use S/S screws around 15mm (5/8th") to 19m (3/4")which should be enough. Bonding them (skegs) onto the glass should be sufficient if a little triangular in section and not too tall.
     
  10. DCockey
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    DCockey Senior Member

    Are the oars too low relative to the thwarts (seats) and rowers' legs? If so consider lowering the thwarts. Lowering the thwarts will also increase stability while being rowed.
     
  11. SukiSolo
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    SukiSolo Senior Member

    That's a good point David. The thwarts do look high, on most dinghies you need around 415mm (16") + height from thwart/side deck to floor to get reasonably comfortable sailing, some lie across types excepted. Pretty much the same in row and sail combined types ie gigs. Probably a little less in more pure rowing craft especially and obviously right down to near level in sculls. Don't forget you probably need a brace or kick bar on the floor to give your heels some grip too, when in the rowing position. The hull looks a decent enough shape but it could be the 'details' are just not optimised. She's not a mile away in shape either from the Thames skiff type boats, with a flatter bottom. Sort of a hybrid with the old French fishing Dorys.

    So Fealeranger if you are under 1m 82 (6') you probably would feel comfortable with 415mm. If you have long legs or are taller increase the height a little. The thwarts could easily be lowered by adding side knees to spread the load down from the inwhale/gunwhale. Lowering the seat gives better stability when seated and rowing as David says, and may well arrange the oars better for you.
     
  12. Nick.K
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    Nick.K Senior Member

    Hello Fealeranger
    I'm in West Cork, where are you? Gandelows are from around Limerick?
    I was in the LEPD centre (http://www.ledp.ie/) in Limerick where they are resurrecting the gandelows as raced on the Shannon; theirs are timber but the shape looks fairly similar to yours. Years ago I did coastal rowing, (we reached fourth in the all Ireland and third in West Cork) the boats we rowed also look fairly similar.
    Nick
     
  13. DCockey
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    DCockey Senior Member

    Most traditional rowing and row/sail boats in North America have thwarts/seats a lot lower than 16" / 415 mm from the floor boards. Rowing is different than sitting at a table or desk.
     
  14. SukiSolo
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    SukiSolo Senior Member

    Agreed David, rowing is different and note I said 'around'. The reason is it is also a fishing craft, and that is a little less comfortable with your knees too high. A compromise as always. Maybe the optimum work around would be having the kickbar area slightly raised as is done in some row craft in the UK. This gives both lower leg heights desired or at least closer to optimum. Some craft have removeable kickbar braces as I'm sure you have in N America too.

    In fact I use a lot higher than 16" for desk seating etc having found most of the guides/ergo texts etc are not overly accurate.... Can't beat the carved base C18/19th wooden 'kitchen' chairs for some shapes - fit from age 8 thro 80+!. A lot of modern copies are useless.
    On the sculls I used to build we got hold of the most comfortable old shape and used that as a basis of a new pattern. Worked, and still sells now 30+ years on, lots of customers of other (boat) builders preferring it. Body does not change too much.

    In the UK you will find most of the hybrid row/sail from 12-16" depending on purpose. Most of the motorised/row fishing types are at the upper end of this.
    There is nothing to stop Fealeranger from finding the optimum height by using a few rough boxes (as sort of prototype) to get a feel for a comfortable compromise.

    In the UK, we call the foot support position stretchers, and some times they can be altered fore/aft by slot position which accomoadtes different leg length positions. However a lot do not have enough fine tune positions in my experience. Some what strangely the builders of that GRP boat seem to have forgotten such niceties.
     

  15. fealeranger
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    fealeranger Junior Member

    Lowering the seats may not be an option due to our height. The boat is gandelow design but it does look more like a dory boat to me. This is as close to the Cashen gandelow design as I could find in fiberglass. I don't want to do too much altering to the boat as I have no experience so I don't want to destroy it. I am in Co Kerry. The boat is not for racing but it is very fast in the water. I am going to see if I can get someone to take a look at what I am proposing and see if it is worth going ahead with this alteration. I would like to add the center line skeg with 2 shorter skeg, one at each side. this would really help protect the base while keeping straight during rowing.
     
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