Mooring Question - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > Skills and Seamanship > Seamanship & Navigation
 Not a Member? 

Seamanship & Navigation Forum devoted to seamanship and navigation topics, including paper and electronic charting tools.


Reply
 
LinkBack Thread Tools
  #1  
Old 07-31-2007
S/V Perwinkle
 
Join Date: Sep 2006
Location: Sarasota
Posts: 22
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
lmitchell is on a distinguished road
Mooring Question

There is a mooring at my club that is available for rent. My question ... is a 1/2 inch chain strong enough for an 18,000 lb boat. I'm being told, "no problem" but my instincts tell me that seems on the light side for a boat of that displacement.

Thanks,
Lawson
Reply With Quote Quick reply to this message Share with Facebook
  #2  
Old 07-31-2007
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,290
Thanks: 0
Thanked 11 Times in 11 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
Lmitchell-

It really depends. If it is G70 or G40/43 chain, it probably is just fine for your boat. 1/2" chain is pretty massive.

I doubt that your windlass uses more than 3/8" chain.

BTW, 1/2" G43 High-test chain has a SWL of 9200 lbs. I seriously doubt that the mooring itself can handle that much strain, unless it is a large diameter square-shaft helix mooring. The mooring system is only as good as the weakest link, which would probably be your mooring pennant.
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.

Last edited by sailingdog; 07-31-2007 at 06:23 PM.
Reply With Quote Quick reply to this message Share with Facebook
  #3  
Old 07-31-2007
LittleMissMagic's Avatar
San Juan 26
 
Join Date: Oct 2006
Location: Robertsdale, AL
Posts: 395
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 9
LittleMissMagic is on a distinguished road
If you can get your hands on a Mar/Apr issue of Good Old Boat there is a good article concerning moorings. If I remember correctly, there is a formula for figuring out what size chain, weight, etc. you need for your boats displacement.
__________________
Jon Caisson Bozeman
S/V Little Miss Magic, Pirates Cove, AL
Reply With Quote Quick reply to this message Share with Facebook
  #4  
Old 07-31-2007
Missionary
 
Join Date: Jan 2007
Location: Smithfield, Virginia
Posts: 23
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
Missionary is on a distinguished road
Has the chain been inspected by a diver. Chain wears it may have started at 1/2 but has worn to only 1/8 in one place and may break any time. Inspection will ease your mind.
Reply With Quote Quick reply to this message Share with Facebook
  #5  
Old 11-10-2007
merttan's Avatar
Senior Member
 
Join Date: Oct 2007
Location: CT
Posts: 317
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 8
merttan is on a distinguished road
I need to know...

There are some unknown factors if you want to share;
Mooring weight.
Mooring line lenght.
Your boats hull height from the waterline.
Type (grade) of chain.

Then I may be able to make a calculation for safety of the chain for known/perfect condition. The known/perfect condition is being that we assume you don't have a weak link such as a weak connection on mooring weight or line, and your cleats are permanent to the boat...

Your boat is moored by the weight of the mooring post, suction of the mud at the bottom,chain strength, and the angle of mooring line (That's why they recommend using a 7:1 ratio for over night anchorages)...
__________________
" I refuse to engage in an intellectual battle with an unarmed man!"

Materialism: Buying the things we don't need, with money we don't have, to impress people who don't matter.

Last edited by merttan; 11-11-2007 at 01:01 AM.
Reply With Quote Quick reply to this message Share with Facebook
  #6  
Old 11-10-2007
deniseO30's Avatar
1934 Chickering
 
Join Date: Nov 2006
Location: Bristol pa
Posts: 6,348
Thanks: 52
Thanked 101 Times in 91 Posts
Rep Power: 10
deniseO30 will become famous soon enough deniseO30 will become famous soon enough
I had the guys put 20ft of 5/8" for bottom chain and I have 5/16 for my 11,000 lb oday 30. the river here has a tidal rush up to up to about 8 knots.
I would rather the mooring move then the chain break because it just resets not too far away. when the chain breaks... bye bye boatie!
__________________
Denise, Bristol PA, Oday 30. On Tidal Delaware River, Anchor Yacht Club. New Website!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

My boat is for sale.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Quick reply to this message Share with Facebook
  #7  
Old 11-11-2007
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,290
Thanks: 0
Thanked 11 Times in 11 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
Merttan-

Not all moorings are weight depended, and the mooring anchor's material makes a huge difference in its holding ability. A 500 lb. block of iron is going to be far better than 500 lbs. of concrete, since iron is far denser and has a much higher effective weight underwater. Many new moorings are helical screw, and basically limited by the type of bottom and what size screw they used. In some tests these helical mooring anchors rated well over 20,000 lbs of resistance before yielding.
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
Reply With Quote Quick reply to this message Share with Facebook
  #8  
Old 11-11-2007
CapnHand's Avatar
humble pie rat
 
Join Date: Nov 2006
Location: Location, Location
Posts: 867
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 9
CapnHand is on a distinguished road
Quote:
Originally Posted by LittleMissMagic View Post
If you can get your hands on a Mar/Apr issue of Good Old Boat there is a good article concerning moorings. If I remember correctly, there is a formula for figuring out what size chain, weight, etc. you need for your boats displacement.
It was graciously posted here by the good people at Good Old Boat: Mooring systems
__________________
There are 10 kinds of people. Those who understand binary and those who don't.
Reply With Quote Quick reply to this message Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Dumb Question about Mooring flyingdiva Boat Review and Purchase Forum 7 06-24-2007 11:23 PM
Special Mooring Challenge like2sail General Discussion (sailing related) 17 04-12-2007 10:51 AM
Mooring Equipment question Dcneuro Bristol 0 11-08-2006 09:39 AM
Mediterranean Mooring John Kretschmer Seamanship Articles 0 12-22-2003 08:00 PM
The Mechanics of Mooring Mark Matthews Seamanship Articles 0 05-19-2002 09:00 PM


All times are GMT -4. The time now is 03:17 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.