How to make steel better

Discussion in 'Boat Design' started by Mik the stick, Jan 13, 2014.

  1. Mik the stick
    Joined: Dec 2012
    Posts: 189
    Likes: 0, Points: 0, Legacy Rep: 6
    Location: Devon

    Mik the stick Senior Member

    In spite of the fact that I think the Titanic sank from neglect rather than the Iceberg it hit. My idea should make a steel boat a bit stronger, and its about the everyday things your boat gets hit with. You can't beat steel for strength but scratch the paint and it rusts almost immediatly. so PREVENTION rather than cure.

    1 Prepare the steel normally and undercoat.
    2 Fit an inside skin about 3" inside the outside hull plates this distance depends to some extent on the design of the ship/boat. The skin would be perhaps 6mm marine ply.
    3 Fill this space with foam as you would a cavity wall in your home. Now you have a laminate, which is stronger and insulates from noise heat/cold No air/oxygen can get at the steel so it won't rust from the inside.
    4 finally cold molded boats have FRP/epoxy coats to give them abrasion resistance and extra strength. Give the boat 10/20oz coat and paint any
    colour you please.
    20oz epoxy/glass would protect better and repair easier than any paint I ever heard of. And If you make sure no-one has dropped brass nails onto the external plates electrolosis won't be a problem either.
    I don't know how finacially viable this idea is, but I think it is a good one.
  2. Waterwitch
    Joined: Oct 2012
    Posts: 101
    Likes: 14, Points: 18, Legacy Rep: 20
    Location: North East USA

    Waterwitch Senior Member

    I think you have a solution looking for a problem. With ships the lower sections are composed of tank spaces, many of them are intentionally filled with raw sea water. There are literally thousands of zincs in those bilge spaces for electrolytic protection. The epoxy paints that are used are pretty tough, as is the powder coating used on other parts like hatches. The hull is pretty much insulated inside with much thinner lighter easily removeable insulation so that you can get at the structure for repairs or modifications. With steel hulls sometimes you have to cut a hole in the side to replace big pieces of machinery, and the patch welded back in place. Ship board fire is a great concern, can you imagine what your 3 inch thick foam and wood will do if it starts burning? Never heard if a foam that does not eventually get water logged.
  3. rwatson
    Joined: Aug 2007
    Posts: 5,852
    Likes: 290, Points: 83, Legacy Rep: 1749
    Location: Tasmania,Australia

    rwatson Senior Member

    Then you ought to read a bit more.

    It was caused by use of below spec rivets, because of the difficulty of inserting them near the bow.

    It puzzles me that you could think that a ship on its maiden ( first ) voyage could have been neglected.
  4. Ad Hoc
    Joined: Oct 2008
    Posts: 6,610
    Likes: 617, Points: 113, Legacy Rep: 2488
    Location: Japan

    Ad Hoc Naval Architect

    I wont even bother addressing the differences in mechanical properties of the two. However, when the survey goes to inspect the work 1) after fabrication and 2) after several years in does the surveyor inspect the integrity of the material and joints.....can't! If it cannot be inspected, it is not acceptable.

    However all you're describing is basically this product:

    Which required significant testing before being approved. But type approved and with rules as noted by LR rules here:

    Attached Files:

    • 419.pdf
      File size:
      763 KB
  5. Mik the stick
    Joined: Dec 2012
    Posts: 189
    Likes: 0, Points: 0, Legacy Rep: 6
    Location: Devon

    Mik the stick Senior Member

    Not sure if the sandwich plate is quite the same as I tried to describe, but I,m not surprised someone has had a similar idea.
    As regards the Titanic I don't want to cause an argument. But I have one book on the Titanic and have read little of it yet. However I was aware rivets were blamed, the rudder was claimed to be too small by some, there may have been more problems than that, who knows?

    The neglect I refer to is the owners neglected to put enough lifeboats on for the number of passengers even though it was legal to go to sea with what they had.
    The Captain neglected to slow down when in Iceberg country, I think but am but certain he neglected to post extra lookouts. He neglected to have competent officers on the bridge. As far as I know nobody tried to build up the bulkheads to slow the flooding. This last is harsh criticism from a non sailor but is based on my book says everybody knows (I didn't) that a head on impact with an iceberg is less damaging than a side impact.
    I recon if the rudder was bigger it might have avoided the Iceberg, trying to slow down and turn was a bad move. The turn would (perhaps) have been faster if done at max speed with more rudder bite. A boat sort of skid turns unlike a car. My book says If Titanic had been put in reverse the bow would have crumpled but the bulkheads would have held and not allow compartments to flood in turn to sink the ship. But that's not human nature and if they had reversed and crumpled the bow I bet the officers would have been crucified just the same.
    However anyone else views this disaster I feel the Titanic should not have been lost.I mentioned the Titanic because anything which strengthens a hull reduces potential impact damage.

  6. longcours62
    Joined: Jul 2011
    Posts: 92
    Likes: 4, Points: 0, Legacy Rep: 47
    Location: France

    longcours62 Junior Member

    Near similar things : double skin on an aloy boat , filled by foam betwen skin.

    Périple 50
    Glory of the sea

    Concept Peignon
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.