painting a steel hull

Discussion in 'Materials' started by mikewade, Jun 4, 2010.

  1. mikewade
    Joined: Oct 2009
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    mikewade Junior Member

    I will be shotblasting my 34' Van De Stadt steel hull in the next three weeks & then epoxy coating and fairing the whole hull. I dont want to use epoxy tar this time prefering a number of epoxy coats over bare metal first, up to the toe rail & then painting the hull.
    My question is really about painting at the waterline. Should I just paint up to the waterline then antifoul below, or should I paint up to say 6 inches or so below the waterline and then cover that section of the paint with the antifoul up to the waterline.
    My previous paint was up to the waterline, then epoxy tar and it is noticeable that paint at the waterline is flaking off. Any advice is most welcome guys.
     
  2. gonzo
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    gonzo Senior Member

    It depends on what paint and primer you use. There is no advantage on applying topsides paint below the waterline though.
     
  3. Landlubber
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    Landlubber Senior Member

    ....no, you do NOT use topside paint below the water line at all, polyurethane is not for permanent imersion.

    there should be a "wind and weatherline" section above the true waterline and below the topside paint. It is oftn done using antifoul as this allows for variable weights to settle the boat down and still be antifouled.

    On a 34 footer I would allow about 3 to 4 inches of extra antifouling above the true waterline. It can be finished with a boot top line, which looks attractive. Paper the boot topping also. Boot tops are usually only 1 to 2 inches.

    I would suggest that the antifoul to be 4 inches at the bow tapering down to 3 inches at the stern, it looks nice and works well.
     
  4. apex1

    apex1 Guest

    Concur,

    never go with the top paint to the bottom, but vice versa.

    Regards
    Richard
     
  5. mikewade
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    mikewade Junior Member

    Hello Landlubber - thanks for detailed reply. I do not quite understand what you mean by paper the boot top line. If I understand correctly, the antifoul extends as you describe and the top side paint extends only down to that antifoul & no more. If you can describe the boot top line in more detail that would be a great help. Is this boot top a different colour antifoul between the bottom and the top paint? is it a hard antifoul or eroding?
    Just treat me as a novice and thanks for answering possibly obvious questions
    Mike
     
  6. Landlubber
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    Landlubber Senior Member

    Hi mate, paper is a typo, it should read taper...sorry.

    OK again to describe the process, the underwater painted section must extent to above the true lwl, by approx 4 inches in the 34 footer. This area will be antifouled as well. Above the antifouled line is placed a boot top line, this is often white to contrast with the topsides and the antifoul, or if the topsides are white then the boot top line could be blue for instance. It provides a visual separation of the topside paint and the antifoul, and is always above the waterline by a few inches at least.
    Somtimes the boot top line can actually be two lines, one fatter than the other, but this of course costs more money and maintenance as time goes by.

    By tapering the line from the bow to the stern, the visual effect is enhanced, the bows look to rise highter from the water and the stern appears to squat or be at least level....it is only a cosmetic thing, but it does show that the owner cares about details....the old "Bristol fashion" as a description of a fine yacht would compliment my comments.

    Today many of the finer things in life are forgotten for the sake of practicality...have a look at a Ro Ro ship for instance, fugly to say the least, but ultimately practical for the purpose of the design.

    Yachts on the other hand a re a reflection of their owners, or at least the builders pride and expression......
     
  7. Landlubber
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    Landlubber Senior Member

    ....one little hint when laying tape for masking...use 3M fine line (it is tape from a plastic that when used results in a very sharp cut edge). if you are right handed, tape from the left to the right and sight along the line with your right eye looking left, this will result in the straightest line visually possibly by hand. Remove the tape as soon as possible after painting, do not allow the paint to dry on the tape, and pull the tape over itself so the edge is cut nicely as you pull off the tape. The result will be a knife sdge sharp line.

    The antifouling top line can have a slight taper from bow to stern too of course if so desired, but a truely parallel line with the tapered boot top to me looks better, otghers will differ of course as there are dozens of ways to "skin a cat".....
     
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  8. mikewade
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    mikewade Junior Member

    Thanks for that landlubber - after I posted my last questions to you I spent some time googling the questions (maybe should have done that first?) and there are loads of material there for all to find. I understand the taper & will apply it as it all gets painted up. Although she is steel she has very pretty lines and I think the taper will further enhance her so thanks once again.
    ps - just returned from 7 weeks in Australia, only 2 places we didnt visit was Brisbane & Tasmania although we met a couple from Brisbane touring in their camper van and had done so for over a year. So now we have set our hearts on going back and visiting these places.
    Mike
     
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