Deck Stepping

Discussion in 'Stability' started by MikeH007, Jun 20, 2013.

  1. MikeH007
    Joined: Jun 2011
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    Location: Ohio

    MikeH007 Junior Member

    Rhodes 22 mast step fitting is surface screwed to the cored deck. The builder discourages through bolting through the solid glass and ply core cabin top. Mfg argues better to let screws fail in dismasting. Through bolts would rip open the cabin top and cause more damage. Of course, it take a whole lot more force than if the mast step was screwed down. I contend, in a blow the screws would strip out more easily. Then you would haver a flying mast loose and endangering crew and skipper. Is the theory for using screws valid ?
     
  2. philSweet
    Joined: May 2008
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    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member

    The compression on the mast is what really holds the thing in place. The screws are just locators. You could just as easily fit the heel of the mast into a little divot and call it good.

    Typically, the mast will buckle and fold down. The mast step will get pryed up on one side and maybe break free. If you throughbolt the base, you need to make sure you can buckle the mast section right at the base without damaging the cabin. That probably isn't the case in a Rhodes 22. Designing things to fail in a predictable way is good engineering. Praying it won't fail isn't.
     
  3. MikeH007
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    MikeH007 Junior Member

    Phil: do you own a Rhodes ? If not your nonpartisan opinion is really helpful.
     
  4. jehardiman
    Joined: Aug 2004
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    jehardiman Senior Member

    Catalina 22 is similiar. Step plate is screwed through the cabintop into the compression post. Again, they say don't through bolt it or add turning blocks to the deck. Catalina supplies a block plate to go under the step so the mast in loaded in compression vice pulling up on the cabintop.
     
  5. Petros
    Joined: Oct 2007
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    Petros Senior Member

    through bolting will actually weaken the cabin top, and raise the potential for moisture intrusion into the core, and possible leak all the way through to the cabin. I would not do it, there should be no significant load on the step that through bolting will control. You only need to hold it in place for the convenience of setting up the mast.

    If you wanted more strength at this connection, how about bonding it down with polyurethane adhesive, along with the screws, that will also help keep moisture out from under the step.
     
  6. Steve W
    Joined: Jul 2004
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    Location: Duluth, Minnesota

    Steve W Senior Member

    A screw is just as likely to leak water into a core as a bolt is, but fortunately it is not likely that there will be core under the mast. I own a boat with a deck stepped mast that I bought from an insurance company because it was totaled because the mast came down. The only damage was the bottom of the mast was flared out where it went sideways off the base which went up about 1.5" inside and a dent in the wall in the side of the top panel. It did no damage at all to the cabintop. To be honest I don't remember if the base was screwed or bolted but it made no difference.

    Steve.
     

  7. MikeH007
    Joined: Jun 2011
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    MikeH007 Junior Member

    Actually the set up we are using affords little chance for water infiltration. The mast step is not directly over the compression post so there is core material. The epoxy forms a watertight seal around the bolt and strengthens the surrounding cabin top that had been damaged while the boat was stored outside with virtually no protections. The bolt is threaded. Laying a sealant 4200 barrier around the perimeter of the deck step fitting pretty much precludes any water invasion. After, considering the great feedback, we will revert to replacing the bolts with screws. By the way, for many if not most older boats, it does not take much for the repari cost to be more than 50% or 60% of the boat value. That will cause the insurance company to total it as is.
     
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