Spash well drain holes

Discussion in 'Fiberglass and Composite Boat Building' started by valvebounce, Nov 4, 2016.

  1. valvebounce
    Joined: Dec 2010
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    valvebounce Senior Member

    Hello,I purchased a 14' fibreglass boat a few months ago.
    The drain holes are 1/4" higher than the splash well floor.
    It has an ally transom protector sheet with two drain holes in it,which has two piped through
    tubes,that are peened in at both ends.
    The last 1/4" of water stays in the well,which is not a problem when the boat is in use.
    I sometimes leave the boat uncovered,and the rainwater stays in the well,and picks up dust etc.
    My idea is to raise the splash well floor with fibreglass resin,I am thinking of adding some chopped strand mat to raise the height and strengthen the resin.
    The water at present is level with the bottom of the holes,the boat is level port to starboard.
    Would I get away with just pouring in the resin to the same level as the water,or would I need to use the chopped strand mat?
    I would of course prepare the surface before adding the resin.
     
  2. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    Rather than making a laminate, consider just thickening the resin, with milled fibers and silica. The CSM isn't going to add much strength, it's just a bulking agent. You can also consider some form of filler to help make up the difference in height between the splash well bottom and the bottom of the drains. 1/4" plywood, intombed in resin will make short work of it, as would several other materials. Lower (jack) the front of the boat down a bit when you do this, so the splash well bottom maintains a healthy slope aft, after you do this.
     
  3. Tiny Turnip
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    Tiny Turnip Senior Member

    Erm, don't you need to jack up the rear of the boat when pouring the resin, so it is thicker towards the front of the well, and forms a slope aft when set level again?
     
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  4. PAR
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    PAR Yacht Designer/Builder

    Yep, good catch Tiny Turnip, I've corrected the post to lowering the bow, again to keep the aft slope, when resin is poured in.
     
  5. valvebounce
    Joined: Dec 2010
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    valvebounce Senior Member

    Hi PAR and TT,
    Thanks for your replies,
    the well has a decent fall from fore to aft,with the boat level fore to aft,which eliminates the need for jacking up the stern.
    The resin will form an elongated "D" shape from 1/4" deep to nil over a distance of about 4" wide fore to aft by about 10" wide port to starboard.
    I will add a small amount of bulking agent and it will find it's own level to the bottom of the drain holes.
    My concern was if the resin would set and be strong enough with being 1/4"deep to infinity
    on the edge of the "D" shape.
    Many thanks for your interest.
    "V"
     
  6. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    Use a milled fiber mix (no silica, just lots of milled fibers). We call this stuff liquid 'glass, as it'll still run and self level, but the fibers will add a ton of stiffness and grip, especially to well toothed 'glass.
     
  7. valvebounce
    Joined: Dec 2010
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    valvebounce Senior Member

    Ok PAR,thanks.
    I'll check the availability in the UK.
    I tried out,"slate dust" for one application.It set has hard as a rock.Using a normal rasp was ineffective.
    Sanding it down took a lot of effort,even with a sander.Not that I intend to use it on this project,but I thought you might like the info.
    "V"
     
  8. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    Slate dust is rock and I've used various stone dusts many times. I prefer decomposed granite.
     
  9. valvebounce
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    valvebounce Senior Member

    They say whatever you use it must be inert.I thought about trying cement,but it is still active.
     
  10. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    You only need to go up 1/4" ? Try a bead of silicone or something similar roof plumbers use, done in a jiffy.
     
  11. valvebounce
    Joined: Dec 2010
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    valvebounce Senior Member

    Hello again Mr E,
    Thanks for your idea,but because it needs feathering from 1/4" to nothing it would still hold water.
    If you can imagine an elongated "D" shape with the curved part of the D being the edge of the feathering and the straight line of the D being at the 1/4" thickness against the transom,
    and being about 4" wide at the widest point of the D,there would be a need for feathering.
    Unfortunately,the drain holes were put in too high.There is a decent fall on the splash well
    floor.There is water in it now,so I can see the shape the resin will take.
    With the weather here in the UK and the pollutants in the air leaving any water in it would probably lead to a rotting transom.
    Most of the attachments had been removed before bought the boat and the holes filled with silicon,I intend removing the silicon and glassing them over.
    Not only is there a risk of the silicon popping out,but it makes the boat look tatty.
    I must admit,silicon can be a handy fix in some cases.
     
  12. SukiSolo
    Joined: Dec 2012
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    SukiSolo Senior Member

    Yup a lot of silicone 'fixes' are a joke and incorrect compared to drilling/abrading and reglassing. Main thing is to ensure that ALL traces of the wretched stuff are removed prior to bonding a proper repair/fill in place. Silicone does have it's uses but not for plugging rowlock holes, old engine mount holes and the like!
     
  13. valvebounce
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    valvebounce Senior Member

    Hello SS,
    It does take the edge off the boat,overall there must be 20 pin and screw holes.
    A couple could be detrimental if they pop out.
    I can't claim the boat is a showstopper,but I always look at it like it is a reflection of my efforts.
     
  14. gtflash
    Joined: Jun 2006
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    gtflash Senior Member

    Does this liquid glass look smooth/polished or does it look rough? In other words how could this be done to a gel coated surface?
     

  15. valvebounce
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    valvebounce Senior Member

    Luckily,because it is finding it's own level,it will be flat and smooth.It will still need abrading
    to take a topcoat.
    Any other angled surface would need sanding before the topcoat.
    All fibreglass will need the topcoat removing down to the original fibreglass to gain a bond,
    then sanding before re-applying the topcoat.
     
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