bearings for freestanding rotating mast

Discussion in 'Sailboats' started by Timothy, Aug 10, 2009.

  1. Timothy
    Joined: Oct 2004
    Posts: 307
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    Location: canada

    Timothy Senior Member

    Would it be possible or practical for the home builder to make two simple bushings from uhmwpe ,one inset in the top and slightly proud of a carbon tubular stub mast ,the other at at deck level around the stub mast and made with a flange ,so that a tubular mast of the right diameter and made with a sort of bell housing and flange at the bottom to accommodate the deck level bearing, could be dropped down around the whole assembly? If not has anybody any sugestions as to how a homebuilder might tackle this problem?

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  2. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    I just did this (twice) on a cat ketch recently. I didn't use an internal bearing, all were external and the spars were aluminum. The partner bearing was just a doughnut with and the heel bearing was as you've described a flange. I also drilled a few slots for moisture drainage. It worked well (still does) with little friction. Don't over think it, the self lubricating properties will bail you out. I used through fasteners on the partners and #14 screws on the step bearing to the keel batten.
    sandpiper32 likes this.
  3. ancient kayaker
    Joined: Aug 2006
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    Location: Alliston, Ontario, Canada

    ancient kayaker aka Terry Haines

    I had an even simpler arrangement for a rotating mast on a small sail, consisting of a tubular aluminum mast fitted over a steel tube with a thin sacrificial aluminum liner between. Although intended as a temporary trial for experimenting; it worked fine for a long time without lubrication, the liner was only replaced once. The bearing length was about 8% of the mast hieght.
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