How To Join Fiberglass Roving Sections

Discussion in 'Fiberglass and Composite Boat Building' started by wamosjk, Oct 24, 2017.

  1. wamosjk
    Joined: Oct 2017
    Posts: 2
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    Location: Omaha, Ne

    wamosjk New Member

    I am currently building a small portable fishing boat and I was wondering what the best practices are for joining 2 pieces of roving for the strongest bond. This is my first boat that I am building from scratch and I have some 24 oz roving but it is only 36in wide. I was wondering how I should go about doing the seams. Should I:

    A. Butt the two pieces up against each other and just resin over it with them butted together evenly.
    B. Butt the two pieces together and then cut some 4oz cloth and go over that seam with strips of cloth.
    C. Overlap them and resin over that.

    Or is there a better way to go about this. I am using polyester resin for the process.
     
  2. ondarvr
    Joined: Dec 2005
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    Location: Monroe WA

    ondarvr Senior Member

    What is your entire plan, or build process? Depending what you're planning you may need to rethink a lot of it.
     
  3. wamosjk
    Joined: Oct 2017
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    Location: Omaha, Ne

    wamosjk New Member

    I am basically building something similar to this but a little bigger. It will be 2 1/2 ft wide by 4 1/2 ft long and 18 inches deep in the main section. My plan is to cover the entire bottom with a single sheet of roving but it will only go about three inches up the sides so I am wondering what the best way to join the pieces of roving to continue up the sides.

     
  4. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Welcome to the forum.

    Cover the bottom first, then allow the fabric pieces on the side to overlap the bottom piece, by at least a few inches. This will leave a bump, which is normal and you'll "fair" this smooth come prep for paint time. Done this way, the bottom piece is captured under the topside piece, so water can't work it's way around a butt joint or seam, simply by gravity pulling on it.
     
  5. ondarvr
    Joined: Dec 2005
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    Location: Monroe WA

    ondarvr Senior Member

    Are you making this shape in a mold, or is there are wood or foam shape you're covering?

    Frequently the glass is overlapped on the chine, so overlapping 3" on each side of the chine with the roving would be normal.
     
    Last edited: Oct 25, 2017
  6. fallguy
    Joined: Dec 2016
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    Location: usa

    fallguy Senior Member

    overlap the bonds at the chine, run bottom piece of roving over the side about 3" and run the side piece of roving over the bottom 3"; you'll need a radius to allow it, work wet on wet, if you get the bottom laid, and start on the sides, the bottom can be tacking up while you do the sides I think

    I'm not a polyester expert, but pretty sure the only way to get a chemical bond would be wet on wet and if you let the roving dry on the bottom, the bond will never be as good from what I've read.

    Who did the lamination schedule? I'm surprised it is roving. You could probably use something much lighter on the sides. I think my canoe uses 6 ounce fabric on the sides and doubled on the bottom. It does have an ash gunnel to support the hull, though. Much nicer to work with and the sides of your boat are less exposed than my canoe sides. The roving on the bottom is okay, but also sort of a weird callout of fabric. If you want something tough, you can get tough with a small piece of aramid that only costs 20 bucks a yard.

    Looks like a fun project. Be careful about making it too heavy or unless the boat is in the same pond/lake/river, you won't like lugging it around. Light is really nice, and a boat like this is meant to puddle jump. If you are guessing on the lamination; you are guessing wrong. You can put 5 ounce Kevlar on the bottom of those tiny hulls for just a bit more cost compared to 18 ounce roving. The resin would be all wore out of the fabric and it'd still be protecting the hull. Although it can be tough to cut, etc.
     

  7. SamSam
    Joined: Feb 2005
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    Location: Coastal Georgia

    SamSam Senior Member

    Laps or more laminations on the chines and other areas of high wear or "abuse" are good.
     
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