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

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

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 11-08-2008, 10:42 AM
Day Tripper Day Tripper is offline
Junior Member
 
Join Date: Nov 2008
Rep: 10 Posts: 11
Location: Maui
36 x 18 ft cat needs mast help

This boat originally had an A-Frame or Bipod rig, loose footed main and two working jibs. I am looking for knowledgable advise on how to rig with a conventional mast or should I try to re rig with the original A-frame design. I bought this boat as a project, which it certainly has been and is now ready for rigging. I have a 40 ft single spreader mast weighing 220# that came off a Trimaran. I have been told it may be too heavy for this 6,000 # boat. Anyone out there that can help?
Attached Thumbnails
36 x 18 ft cat needs mast help-cat1.jpg  36 x 18 ft cat needs mast help-valkthm.jpg  
Reply With Quote
  #2  
Old 11-09-2008, 04:40 AM
SPJ yachts SPJ yachts is offline
Junior Member
 
Join Date: Feb 2007
Rep: 10 Posts: 21
Location: Queensland Australia
Day tripper
forget the tripod stay with an conventional rig you will have less hassle and the boat will be easer to manage.
Check that the load areas ie mast compression bulkhead and support members, fwd beam @ forstay attachment point and chainplates are up to the task.
SPJ Yachts
Reply With Quote
  #3  
Old 11-09-2008, 09:52 AM
Day Tripper Day Tripper is offline
Junior Member
 
Join Date: Nov 2008
Rep: 10 Posts: 11
Location: Maui
Thanks for your reply SPJ

Going with the traditional mast was my idea from the beginning. It's just making the decisions of using dolphin and pelican strikers and if they are necssessary or not. Chainplates need to be installed etc. The mast is really the question. Is it too heavy? 220# @ 40ft. Other decisions I'm facing are the compression bulkhead and how to build it. I have been told it needs to be made of wood rather than aluminum. The mast will be stepped as a deck mount with a gimbled step base for mast tuning once it gets in the water.

Any input anyone?
Reply With Quote
  #4  
Old 11-09-2008, 10:58 AM
terhohalme's Avatar
terhohalme terhohalme is offline
Senior Member
 
Join Date: Jun 2003
Rep: 478 Posts: 485
Location: Kotka, Finland
The weight of the mast is not the problem. In fact, if the weight of the boat is from an empty one, the mast can fit quite well. Any idea of the manufacturer and type of the mast? Or the trimaran where is was?

The real problems are the strength of the main beam and back beam and the structure of these. You sure need a NA to survey and do the necessary calculation.
__________________
Only shared knowledge can grow.
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
GRP passenger cat OR AL passenger cat? hashem_1064 Boat Design 2 10-13-2008 06:11 AM
which cat for me? Grizz Multihulls 42 10-09-2008 09:35 AM
Rig handling: Cat Ketch, Cat Schooner, Sloop, Cutter Seafarer24 Sailboats 8 05-30-2006 10:06 AM
mast design-how do you go upon calculating the effect of the sail on the mast??? airturb Sailboats 34 02-21-2005 09:55 AM
Payson Cat Mast material tedquist Sailboats 4 08-04-2004 08:00 PM


All times are GMT -5. The time now is 02:22 PM.


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