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s/v Tiger Lily
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Discussion Starter · #1 ·
The bad news: Last night, I looked out into our cove to find that our 500 lbs. mooring system was not in its usual location ... in fact, nowhere to be seen.

The good news: Our boat is on the hard for the winter.

So, this mooring ball was installed with a 500 lbs mushroom in 2009. I found the ball still attached to the lighter top chain on nearby shoreline. I dragged it up on land but I haven't examined it closely yet because the sun was setting and it was raining. It looks like it failed at the first swivel at the bottom of the upper chain.

Is less than four years a short life for a mooring system in a protected cove in brackish water? I thought that I would pull, inspect, and or replace after 5 years being on the cautious side.

I have to forensically go back and examine what we put down there. But was there anything that we could have done incorrectly here?

This is similar to what we had in our setup:
http://www.easternmarine.com/media/downloads/5546/mooring_diagram.7717.jpg
 

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Not all chain is created of the same quallity so I would start by checking what you used and who made it! ...Dale
 

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The swivels are usually the weakest points...Im interested to see it thats where it failed. Why not just use two shackless to connect heavy and light chain?

This may seem dumb, but what not use heavy chain for the whole system?

Where actually is your mooring...on the Magothy? Which cove or creek?
 
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s/v Tiger Lily
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Discussion Starter · #4 · (Edited)
We're on upper Round Bay, Severn River.

My understanding is that if you don't have swivels the whole system binds and fouls. Also if you have heavy chain on the upper part of the system it is too much downward pull on the ball.
 

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s/v Tiger Lily
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Discussion Starter · #6 ·
Are those municipal/organized or commercial moorings or private ones too that are pulled each year?
 

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The bad news: Last night, I looked out into our cove to find that our 500 lbs. mooring system was not in its usual location ... in fact, nowhere to be seen.

The good news: Our boat is on the hard for the winter.

So, this mooring ball was installed with a 500 lbs mushroom in 2009. I found the ball still attached to the lighter top chain on nearby shoreline. I dragged it up on land but I haven't examined it closely yet because the sun was setting and it was raining. It looks like it failed at the first swivel at the bottom of the upper chain.

Is less than four years a short life for a mooring system in a protected cove in brackish water? I thought that I would pull, inspect, and or replace after 5 years being on the cautious side.

I have to forensically go back and examine what we put down there. But was there anything that we could have done incorrectly here?

This is similar to what we had in our setup:
http://www.easternmarine.com/media/downloads/5546/mooring_diagram.7717.jpg
Some thoughts...

* I would not place a swivel anywhere but at the ball so it can be expected regularly.. SWIVELS MUST BE LARGE!!!

* I would not install any swivel smaller than 3/4". I use an 1 1/4" swivel on a 36 footer. My top chain is 3/4" long link mooring chain and my bottom chain is 1 1/2" US Navy chain at nearly 22 pounds per foot.

* The chain and swivel should be "winterized" by installing a winter spar which allows the chain to be dropped to the bottom, stop wear and sit in the low oxygen mud bottom....

* Moorings should be inspected yearly or bi-yearly at a minimum. Top chain should really not be any smaller than 5/8 and really that is tiny chain for a permanent mooring.....

* Swivels are the highest wear item therefore they need to be directly below the ball. They should also be VERY LARGE so as they wear they don't wear faster than the top chain.

On a permanent mooring a top swivel is usually very necessary especially in areas of high tidal ranges as the boat swings around, and around, and around sometimes for weeks depending upon usage. Do this enough and the chain twists and shortens to 1:1 scope and sucks the ball under. If a storm comes up you simply un-set the mooring and drag it or shock load the gear until you have a failure.

The problem with the vast majority of moorings is they are grossly under designed. Swivels are too small, placed in the wrong locations or are of an unsuitable design.

Chain is also almost always far to light/small for storm purposes and "shock loads" the gear.

At a minimum for our boat (36') my design criteria is:

*8000 Pounds of granite (actual storm mooring is 9600 pounds), 500 pound mushroom (min) or screw mooring
*USCG/USN bottom chain (1 1/2" X 22 pounds per foot) to 1.5 X Depth
*3/4" Top chain to 1X depth
*1" Swivel MINIMUM directly below ball (actual is 1 1/4")
*Dual unequal length polyester pendants with Vectran storm snugs added to go over the chocks in storms.

I use a 1 1/4" swivel for our CS-36. Our town requires a top swivel on moorings as part of the local ordinance.

This is my eye to eye swivel for a 36 footer.
Swivel Eye To Eye 1 1/4"" Galvanized Made In USA

This is the bottom chain on one of our moorings, the lighter of the two. My storm mooring is the type with the cross bars in the links.
 

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In my area they are hauled and inspected annually
Unless these are all deadweight moorings this is actually poor form dictated by a town without not much of a clue about proper mooring protocol. Yes the chain can be inspected but the moorings are all "barely set" which creates even lots of potential for danger in storms.

Mushroom and pyramid style moorings, and even dead weight moorings, can take months to properly set. Every time you un-set one you open up your potential for dragging the mooring because it is not yet set well. Inspections ideally should be done by town certified divers.

I will not let anyone un-set my mushroom mooring. It is 6' into the bottom..... That type of set takes a few years to attain....
 

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Some thoughts...

* I would not place a swivel anywhere but at the ball so it can be expected regularly.. SWIVELS MUST BE LARGE!!!

* I would not install any swivel smaller than 3/4". I use an 1 1/4" swivel on a 36 footer. My top chain is 3/4" long link mooring chain and my bottom chain is 1 1/2" US Navy chain at nearly 22 pounds per foot.

* The chain and swivel should be "winterized" by installing a winter spar which allows the chain to be dropped to the bottom, stop wear and sit in the low oxygen mud bottom....

* Moorings should be inspected yearly or bi-yearly at a minimum. Top chain should really not be any smaller than 5/8 and really that is tiny chain for a permanent mooring.....

* Swivels are the highest wear item therefore they need to be directly below the ball. They should also be VERY LARGE so as they wear they don't wear faster than the top chain.

On a permanent mooring a top swivel is usually very necessary especially in areas of high tidal ranges as the boat swings around, and around, and around sometimes for weeks depending upon usage. Do this enough and the chain twists and shortens to 1:1 scope and sucks the ball under. If a storm comes up you simply un-set the mooring and drag it or shock load the gear until you have a failure.

The problem with the vast majority of moorings is they are grossly under designed. Swivels are too small, placed in the wrong locations or are of an unsuitable design.

Chain is also almost always far to light/small for storm purposes and "shock loads" the gear.

At a minimum for our boat (36') my design criteria is:

*8000 Pounds of granite (actual storm mooring is 9600 pounds), 500 pound mushroom (min) or screw mooring
*USCG/USN bottom chain (1 1/2" X 22 pounds per foot) to 1.5 X Depth
*3/4" Top chain to 1X depth
*1" Swivel MINIMUM directly below ball (actual is 1 1/4")
*Dual unequal length polyester pendants with Vectran storm snugs added to go over the chocks in storms.

I use a 1 1/4" swivel for our CS-36. Our town requires a top swivel on moorings as part of the local ordinance.

This is my eye to eye swivel for a 36 footer.
Swivel Eye To Eye 1 1/4"" Galvanized Made In USA

This is the bottom chain on one of our moorings, the lighter of the two. My storm mooring is the type with the cross bars in the links.
Gotcha on the need for swivel somewhere as it makes sense in "winding up the chain". So you only need the top one so you can inspect it.

Size of chain is impressive to say the least.
 

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Unless these are all deadweight moorings this is actually poor form dictated by a town without not much of a clue about proper mooring protocol. Yes the chain can be inspected but the moorings are all "barely set" which creates even lots of potential for danger in storms.
Hey,

Here in the north shore of Long Island (south side of the LI Sound), the towns regulate moorings. I own my mooring gear but need to purchase a mooring permit each year. The mooring can be placed in the spring and must be hauled by December. The upside is that the place that drops and hauls my mooring also inspects it and replaces components as required.

Barry
 

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Hey,

Here in the north shore of Long Island (south side of the LI Sound), the towns regulate moorings. I own my mooring gear but need to purchase a mooring permit each year. The mooring can be placed in the spring and must be hauled by December. The upside is that the place that drops and hauls my mooring also inspects it and replaces components as required.

Barry
You may want to get on the towns mooring committee to get them to address the issue of continuously un-setting moorings.....:eek: I know many towns think they are doing a good thing by mandating removal but this only causes problems with an entire mooring field of partially set moorings. The harder the bottom type the longer it takes these moorings to properly set. A mushroom "screws" into the bottom by the boat moving around it. A properly set mushroom will have the shank near vertical and the bell buried 3'-6' below the bottom.. My diver charges me $75.00 to dive my mooring and inspect it and it remains set....
 

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Mainsail i understand what your saying and when in orient harbor we dived it and did repairs


BUT in the big picture around here so many people would leave the dam thing in until it failed it seems to give the best result as i have been through many hurricanes and big storms without dragging issues in a field of 800 some odd boats
 

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Mainsail i understand what your saying and when in orient harbor we dived it and did repairs

BUT in the big picture around here so many people would leave the dam thing in until it failed it seems to give the best result as i have been through many hurricanes and big storms without dragging issues in a field of 800 some odd boats
Here in Falmouth we have mandatory mooring inspections. No inspection, no mooring... Get kicked out of the mooring field for failure to comply and you go to the back of the waiting list. It could be a loooong wait... Moorings are a privileged not a guarantee so you need to comply with the local ordinance...

There are only four or five mooring companies "certified" by the town to do these inspections, which keeps the quality of the work consistent, and you MUST have an inspection report on file with the harbormaster to moor your boat..
 

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Maine Sail provided a very good list of suggestions as always. The only thing that I would add is that there are many types of swivels and they are not created equal. The two main differences are the eyes and how they are attached. I like solid eyes which you need to put a shackle into as they are by far the most secure. I would never rely on one with a pin held in by a cotter pin, these are fine in applications where they are inspected regularly and there is no corrosion but they are inappropriate for moorings.

Regarding how the two halves of the swivel are attached, it is done in many different ways including peening a stud over, a nut, a welded nut, and welding. I like a nut that is thoroughly welded on the best. as there is a lot of meat there. I remember seeing a good writeup comparing the types but I unfortunately don't remember where it was.
 

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s/v Tiger Lily
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Discussion Starter · #15 ·
(OP) Here in the Annapolis area, other than not obstructing channels or access, there is an odd lack of rules regarding mooring buoys. You can drop them wherever you like provided that you have access to them. There are no regulations or ordinances about inspections or standards. You're really on your own.

This is good advice. Thanks. Even though we don't have anything close to Maine conditions ... I'm going to upgrade mine to New England standards particularly with the swivel.
 

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It's not a good idea to leave the ball in place during the winter. If you drop the top chain to the bottom, as MaineSail has suggested, it's better for the chain. If it stays hooked up to the ball the top several feet of the chain will wear away faster for two reasons: more O2 in the water to make rust, and the constant motion of the ball moving in wind and swell causes the chain just below the ball to wear faster. Do as MS recommends and drop the top chain into the mud with a line and small bouy attached to facilitate it's recovery in the spring.
 

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Nothing quite like the bond between a man and his mooring! :)
Does the fact that the mooring is in a mostly fresh slighly brackish water have any bearing on corrosion. Our YC has three mooorings just a little further north than the OP and I am going to have them checked after reading what happened to his.
 

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I, too, leave my mooring in. At the end of the boating season, six adjacent mooring owner remove our pendants, tie the moorings together with 3/8" polypropelene line, and drop them for the winter. In the Spring it takes about 15 minutes to grapple for the polypro line. When you find one mooring chain you've found them all.
 

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You may want to get on the towns mooring committee to get them to address the issue of continuously un-setting moorings.....:eek: I know many towns think they are doing a good thing by mandating removal but this only causes problems with an entire mooring field of partially set moorings. The harder the bottom type the longer it takes these moorings to properly set. A mushroom "screws" into the bottom by the boat moving around it. A properly set mushroom will have the shank near vertical and the bell buried 3'-6' below the bottom.. My diver charges me $75.00 to dive my mooring and inspect it and it remains set....
How hard is the bottom? My mooring must be inspected every 3 yrs, but, I've had a diver jet my mooring into the bottom so that it's completely under the mud.

The diver is also a third generation marina owner and swears that getting the mooring gear under the mud not only is better holding but that the iron rusts slower under the muck.
 
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