Best material for seacocks, vents, and fasteners

Discussion in 'Metal Boat Building' started by Tygafan, Dec 4, 2007.

  1. Tygafan
    Joined: Nov 2007
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    Tygafan Junior Member

    I have recently purchased a used steel boat and will be doing a complete refit. What would be the best material choice when selecting seacocks, vent, and fasteners? What method or material should I use to insulate dissimilar metals such as stainless to carbon steel? Any advise would be appreciated.
     
  2. Bergalia
    Joined: Aug 2005
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    Bergalia Senior Member

    Best material for seacocks etc

    For personal preference I'd go for phosphor-bronze fittings. BUT - big but it will be necessary to fit a sacrificial zinc annode (and check it regularly - every careen) somewhere on your hull. Also isolate the fittings via rubber gaskets and/or an insulating hull paint. Whatever you use ensure that all fittings are of a single material. Mixing metals in sea-water rapidly leads to electrolysis/corrosion
     
  3. BruceS
    Joined: Feb 2007
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    BruceS Junior Member

    I'm far from an expert, but wouldn't use rubber gaskets, nor phosphor bronze on a steel boat. Rubber often (always?) contains carbon which would cause galvanic corrosion with the phosphor bronze. I used stainless steel on a previous steel boat, which worked without problems in the five short years I owned the boat.
     
  4. Tygafan
    Joined: Nov 2007
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    Tygafan Junior Member

    Thanks for the advice about the use of rubber gaskets. I was actually thinking of using rubber gaskets to insulate dissimilar metals such as stainless to carbon steel attachments.
    To be more specific, there are some stainless accessories such as railings and flybridge top that are on the boat that I will need to re-attach. What would be the best type of bolts to use?
    When I replace the seacocks and vents I assume that phosphor-bronze would be better than stainless. Or could I use phosphor bronze seacocks and SS vents? I guess that I should use a material other than rubber gasket to insulate?????? I will have numerous anodes installed on the hull.
     
  5. Brent Swain
    Joined: Mar 2002
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    Brent Swain Member

    Welded on stainless is best by far for thru hulls . Stainless ball valves are best for sea cocks.I've been doing that a for over 30 years with no problems.
    Brent
     
  6. Roly
    Joined: Jul 2005
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    Roly Senior Member

    Brent, do you mean stainless through hulls Tig welded to the steel hull with a female ball valve threaded to it? Thx.
     
  7. Guest625101138

    Guest625101138 Previous Member

    A work colleage from my past purchased a steel boat that was owned by a plumber who did all his fittings and piping in stainless steel. Even fuel lines and potable water lines. It was a significant feature in his decision to purchase the boat. He was a fan of plastic boats but the attention to detail with fittings and painting were convincing factors. So don't under estimate the value that these details afford if the boat is eventually sold.

    As a matter of interest the boat had a swing keel and the inside of the case was lined with stainless sheet as it was impossible to paint properly and was subject to wear.

    Rick W.
     

  8. Brent Swain
    Joined: Mar 2002
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    Location: British Columbia

    Brent Swain Member

    Yes . I use stainless sch 40 type 316 pipe nipples stick welded in with stainless rods for thru hulls and stainless type 316 female ball valves threaded on. No problem of any kind for 32 years , except a few pinhead sized bubbles in the paint around them , not enough to be worth worrying about.
    Brent
     
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