17ft coastworker deck design

Discussion in 'Fiberglass and Composite Boat Building' started by Sinnie, Oct 17, 2021.

  1. Sinnie
    Joined: Oct 2021
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    Location: England

    Sinnie Junior Member

    Hello,

    I'm new to this forum and was hoping someone would be able to put my mind at rest / share their thoughts on the draining setup on my boat.

    I'm currently in the process of restoring a coastworker 17 I bought the boat from someone who had fitted a new deck/stringers/bulkheads but was in need of a compete refit.

    ( not the boat in question but gives you an idea}

    So far I have fabricated and fitted gunwhale folded edges, bow, transom splash well, console and seating and im getting close to concluding the structural phase of the refit and moving onto the tedious filling and fairing.


    Now onto the thing I'm unsure about is the really odd self draining setup on this boat. The deck ends about a foot or so before the transom, there are no above waterline scuppers but 2 20mm drains right at the lowest point of the transom which means this 'well' is effectively balanced with the waterline.

    the service channel that runs from the console pops out under the sealed deck into this well, and by the looks of it will be below the waterline at rest. Sealed deck leak risk?

    So my question, should I trust this setup or should i convert to a non self bailing/ bilge pump arrangement?

    I have attached a few images showing the deck before the motor well went in, the service channel and the transom drains.

    Thankyou in advance.
     

    Attached Files:

  2. Blueknarr
    Joined: Aug 2017
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    Blueknarr Senior Member

    Welcome to the group

    Your instinct does you well.
    I would add bilge pump and use those holes as "on trailer drains".
     
  3. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Looks like a boat it would be easy to fall out of, with the low internal depth created by a self-draining cockpit
     
  4. wet feet
    Joined: Nov 2004
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    wet feet Senior Member

    If you have enough power to plane,the existing holes will probably empty the boat at speed.If not the addition of a bilge pump will be the way to remove the water.That has to be one of the smallest boats to have a pot hauler.
     
  5. Sinnie
    Joined: Oct 2021
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    Sinnie Junior Member

    It should hopefully have enough power to get up, there's a 60hp on the way.

    If I kept the design as is then, is there anything inherently wrong with the service channel partly submerged?

    Also when I take it for a test once complete is there a benchmark for how much freeboard the deck has?

    Agree on the pot hauler, I don't have any immediate plans to get into the lobster business!
     
  6. wet feet
    Joined: Nov 2004
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    wet feet Senior Member

    The obvious question is did the boat work as it was?If so,why change it?I have to admit not totally grasping what the various pictures are showing us.I have seen the arrangement in a Dell Quay dory where the well at the stern flooded and the bung was in the bulkhead that separated the working area from the well.At planing speeds it was quite normal to remove the bung (which was on a retaining chain) and drain the boat.The bung was replaced before slowing down and the boat was dry apart from the well which filled to the waterline again.I suspect something similar may have been intended.Any Americans reading this may be perplexed if they look u a Dell Quay dory as it won't be what they might expect.
     
  7. Sinnie
    Joined: Oct 2021
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    Sinnie Junior Member

    Cheers wet feet,

    Hope this poorly drawn cross section helps.

    Note how the service channel will be atleast partially submerged, asking for trouble when things get waterlogged swell up and move in future in terms of leaking into sealed deck area?

    16345488347607954888497474380428.jpg
     
  8. Sinnie
    Joined: Oct 2021
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    Location: England

    Sinnie Junior Member

    I think I have decided what to do,

    Leave as is as you have rightly suggested but swap the transom holes for something with an NRV and a plug. Logic being I have the best of both worlds, dry feet when there's a few people on board, a plug for piece of mind when the boat is in the mooring all whilst retaining some bailing capabilities underway.

    1) does a thru hull scupper with an internal screw bung exist? For a 2" transom

    2) if it does exist, is there a limit to how large of a hole I would want to be making in the transom right near the keel?
     
  9. fallguy
    Joined: Dec 2016
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    fallguy Senior Member

    All the people I know with the likelihood of a wet boat go to duckbill scuppers.

    The setup is weird to me.

    Why are you concerned about the sealed deck leaking? How was it built? If you used polyester, for example, I'd scrap the entire wet boat concept and go to pumps.
     
  10. Sinnie
    Joined: Oct 2021
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    Sinnie Junior Member

    Based purely on the fact I can see csm and smell styrene when abraiding it, the deck was done either PE or VE resin and not hugely thick either, the core from drilling the inspection cover I put in showed the deck laminate is about 2-2.5mm.

    Everything else including the tabbing in I've done for various bits has been in PE resin (Lloyd's grade, not roof grade)

    So this precludes a wet setup?

    And I'm concerned because if the channel let's water through then I'm reliant on the milk bottles underneath to keep the boat afloat.

    I like the look of duckbill scuppers, is there any product out there that you know of that has a plug incorporated into it to prevent filling when the boat is left on mooring ?
     
  11. wet feet
    Joined: Nov 2004
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    wet feet Senior Member

    The boat is guaranteed to be built with polyester resin-more than 99.8% of production boats are.I would suppose that service channel contains the throttle,gearshift and fuel connections and wouldn't be too surprised if the sealed floor section had no provision for drainage.If so and if the sealed floor doesn't leak,the boat may well have sufficient buoyancy to stay afloat with an inch or two of rain or spray inside.A lot of RIBs have a drain tube attached to a transom ring and the tube can be drawn up when the boat is left or whenit is moving slowly.I'm a bit concerned that you know that there are milk bottles beneath the suposedly sealed floor section.
     
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  12. fallguy
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    fallguy Senior Member

    Just make it a dry bilge unless you are doing commercial work and the boat is full of dirty water all day.

    I'd run a double bilge pump system, but I'd stop running water to mysterious places in a refit. Make a couple of nice pumpwells. Use epoxy and marine foam cores or plywood and lots of glass and epoxy. Mount the pumps wothout holing the plywood!

    But ultimately everything depends on use. If you are backing into or experiencing heavy intake of seawater, standard bilge pumps are insufficient. If you are indeed pot pulling and expect lots of debris in the water, punps are a bad idea. But in a refit, running water into strange places = bad.
     
  13. fallguy
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    fallguy Senior Member

    these plugs can be used; there are different sizes

    https://www.go2marine.com/Turn-Tite...MIwZjqj7m08gIVJQh9Ch0OOA3uEAYYAiABEgKgwPD_BwE
     
  14. fallguy
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    fallguy Senior Member

    Also, if you are doing a refit, why not do some calcs and add enough buoyancy foam to keep it afloat? I like the boat..
     

  15. Sinnie
    Joined: Oct 2021
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    Sinnie Junior Member

    I like the idea but, doesn't thst involve removing the deck or is there another way :eek:?
     
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