Boat Design Forums  |  Boat Design Directory  |  Boat Design Gallery  |  Boat Design Book Store  |  Thanks to Our Site Sponsors

Go Back   Boat Design Forums > Design > Sailboats
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 08-10-2009, 04:57 PM
Timothy Timothy is offline
Senior Member
 
Join Date: Oct 2004
Rep: 175 Posts: 187
Location: canada
bearings for freestanding rotating mast

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?
Attached Thumbnails
bearings for freestanding rotating mast-mast-bearings.jpg  
Reply With Quote
  #2  
Old 08-10-2009, 09:43 PM
PAR's Avatar
PAR PAR is offline
Yacht Designer & Builder
 
Join Date: Nov 2003
Rep: 3125 Posts: 9,403
Location: Eustis, FL
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.
Reply With Quote
  #3  
Old 08-11-2009, 02:52 PM
ancient kayaker ancient kayaker is offline
aka Terry Haines
 
Join Date: Aug 2006
Rep: 1814 Posts: 3,009
Location: Alliston, Ontario, Canada
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.
__________________
"Boats are like rabbits; you can have one boat or many, but you can't stop at two" - A. Onassis
Boat designs: "a convoluted collection of discontinuous compromise" - Par
". . . ere the end, some work of noble note, may yet be done . . ." -Tennyson
Dances with Turkeys
Reply With Quote
Reply



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
rotating mast, spanner length simonfraser.97 Boat Design 2 05-17-2009 03:40 PM
Build a Freestanding or buy a Traditional mast? Kaptin-Jer Fiberglass and Composite Boat Building 30 05-07-2008 02:06 AM
Rotating wing mast john olsson Multihulls 4 06-11-2007 07:06 AM
Headstay attachment on rotating mast? henrikb Multihulls 3 03-11-2007 05:04 AM
is it possible to have a freestanding mast on a open 60"? yoshi Boat Design 8 03-18-2005 10:49 AM


All times are GMT -5. The time now is 08:59 PM.


Powered by: vBulletin Copyright ©2000 - 2012, Jelsoft Enterprises Ltd.
Web Site Design and Content Copyright ©1999 - 2012 Boat Design Net