Stringers and floor

Discussion in 'Boat Design' started by Juicy, Mar 11, 2011.

  1. Juicy
    Joined: Mar 2011
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    Location: Australia

    Juicy New Member

    Hello everyone, a complete novice here. We were recently given a Savage Pacific power boat. The floor and transom are completely rotten and we have removed them. The hull of the boat is hard and has no soft spots, which I gather is a good thing. I Have read that one is not supposed to directly attach stringers to the floor of the boat as this could cause the hull to split. This next comment proves my ignorance and I apologise in advance, but how do you attach them to the floor if not directly? Many thanks for any advice and again I apologise for my ignorance. I have three teenage boys and figured this would be a great winter project for them!
     
  2. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    First off welcome to the forum, second my sympathy for the illness that now has over come you and likely that will also affect your boys.

    Stringers on the hull shell will not cause it to split in half, though can cause some deformations we commonly call "oil canning". Depending on the thickness and build method of your boat, this may or may not be an issue.

    The year built, make and model boat will help identify the build type and possably other known issues.

    Next, try to post some photos of the transom and sole (floor) removal. Lets hope you left a flange of some sort, so you have something to attach to. This is a common novice mistake and greatly increases repair difficulty.

    So, post some pictures and the year, make and model information.
     
  3. Juicy
    Joined: Mar 2011
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    Juicy New Member

    Thank you for your reply PAR. Also thanks for your sympathies, yes, sadly have succumbed, but secretly between you, me... (and all members), am enjoying this newly caught illness which keeps me up late at night, gleaning information from forums, finding me up ridiculously early in the morning tinkering with the boat, wishing I knew what the heck I was doing so I could just get on and do it! Having only just found this forum I have been reading posts and replies and have soon realised how lacking in information my question was! So I am off to measure my boat and get exact details for you all. Also taking photos and will upload them as soon as one of the boys come home to show me how to do that!!!!! The boat came as is, and the only reason for my knowing what the boat actually was, was because I found the original plate at the back of the boat, but it doesn't have a date on it. From the net I have discovered that these boats were made from the mid 1970's to the mid 1980's. It came with a Chrysler engine, 75 hp. It is fibreglass. Oops can feel a fever coming on, am off to the boat house to relieve symptoms........ie take measurement etc
     
  4. atonomy
    Joined: Mar 2011
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    Location: melbourne florida

    atonomy Junior Member

    I restore boats for a living, it is a bug that just won't get out of your blood. So welcome to the loonie bin with the rest of us. There are some products out there that can really help you on your quest. Check out my blog, JandSboatrestoration.blogspot.com , we have stated this blog because this is the largest boat we have taken on, its a 1981 23' fish Nautique. usually we do smaller boats. But we have a lot of info about the stringer, transom and decking systems that we used, I think this will be very helpful for you. By the way we use only composite materials in our projects, nothing to rot later, just a thought. Good Luck
     
  5. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    "Composite materials" (read a a lot more money) are generally out of the usual realm of the backyard repair person. Not because they can't do it, but simply from cost.
     
  6. Juicy
    Joined: Mar 2011
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    Location: Australia

    Juicy New Member

    Thank you Atonomy for your imput. I have checked out a product called PRISMA looks very impressive. I have contacted them to get pricings, but as we are in Australia and I havent found anyone who supplies the product here I am wondering if this will be out of our price bracket as PAR said. However I away their reply with baited breath. Quick question...when a boat is designed I guess the weight of everything that will go into the shell of the boat ie stringers, decking, chairs, etc is taken into account. As I have removed wooden stringers and a rather thick deck (have no idea what type of wood it is), if I replace these things with lighter products, will it affect the way the boat moves in the water. Does one require a certain weight in order for the boat to give a smooth ride? I have visions of the boat with wooden stringers sitting lower in the water and with the composites, the boat sitting higher in the water.....ok you can all stop laughing now, was just a vision lol
     
  7. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Don't be so worried about making things lighter, though making things a good bit heavier is to be avoided as this can dramatically affect the preformance envelop.

    The sole (floor) was made of plywood and this sat on top of stringers and other support elements. The sole would have been "tabbed" into the hull shell and covered with fabric to water proof. It's usually quite wise to take photos before you tear things out, so you know what to put back and where.

    The economic choices are plywood and solid wood structural elements. You can get damn fancy with a whole bunch of other materials, but it's hard to beat the pricing and availability of wood. Some of the fancy materials will be 5 - 10 times the cost of a sheet of plywood.
     

  8. atonomy
    Joined: Mar 2011
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    Location: melbourne florida

    atonomy Junior Member

    Juicy,
    Scott and mike from prisma are great people and if they can help you they will do everything in their power to do so. As for the cost you are right it is a bit more than using traditional materials, a properly laminated sheet of plywood is around $90-$110 U.S. and a sheet of properly laminated nidacore is around $200 U.S. but you will never have to do it again. I am very lucky that I live in a town where I have access to these companies, Prisma and compsis are only a few miles from my shop and nidacore and nidabond are just a couple hours ride.

    As for the weight I agree with PAR, I wouldn't worry too much about it. Making the boat lighter will change how it rides in the water but as long as you keep the rest of the structural weight distrubted over the hull evenly you should be fine, you should auctually save a little in fuel.
     
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