Mushroom Mooring Setup

[davidpm]

I have about 12' of water and just bought a used 500 lb mushroom mooring anchor.
The mooring came with 28' of 3/4" chain
20' of 1/2" chain
24" Sur-Moor T3C Mooring Buoy

The location is in the long island sound, sandy bottom.
41° 16' N
72° 37' W
I do not have a boat but I have about 15 friends that have boats from 15' to 51' and I thought it might be fun to put the mooring out so they would have a place to go.
So it is quite exposed and of course the wind and waves often are on-shore. There are several people that moor there every year.

That is the situation now the questions:

• Do the sizes of the above parts make sense for up to a 30' boat?
• The eye of the mushroom looks good but the shank has a lot of 1/4" scale on it. I started to clean it but decided the it might be some protection, what do you think?
• Any comments suggestions etc based on pictures?

[CLucas]

How heavy is the mushroom?

[davidpm]

Oops, edited orginal post to put in the weight, 500 lbs.

[CalebD]

David,
We keep our 7000+ # 27' boat on a similar arrangement only we use a 250# mushroom in the Hudson which has a more muddy, clay-like bottom. I'm pretty sure we use 20' of 5/8" chain and 20' of 1/2" chain in about 18' of water as dictated by the club mooring rules. I know that this largely violates the rule of 'scope' but our mooring field is fairly small so boat swing area is minimized in order to get more boats into the area available.
A 500# mushroom should hold a pretty heavy boat in moderate conditions and most 30' boats in our club would be happy to have that as their mooring anchor since many use just a 350# or so.
As an aside I'll note that the weather that just blew through here brought some 40 knot gusts to our mooring field. One or two boats got away from their moorings - chafed pendants, weakest link etc. Our boat is still on her mooring.
I would not worry about the rust on the shaft of your mushroom. While storing the chain over the winter we have found that coating it with vegetable oil (or any food oil for that matter) can help keep it from oxidizing (eg., rusting). I'm not sure if that would help your rusty mushroom though. Perhaps some Naval Jelly (phosphoric acid) would stem the rust a bit.

[JimsCAL]

Is this going to be used full-time (i.e. must be good for storms) or as a short term mooring in good weather when cruising? If the first, the mooring should be fine for boats to about 35 foot or so, depemding on how exposed you really are. If the later, larger boats will be fine. Don't bother trying to do anything with rust on the mushroom shaft. It won't do anything.

[davidpm]

Originally Posted by JimsCAL

Is this going to be used full-time (i.e. must be good for storms) or as a short term mooring in good weather when cruising? If the first, the mooring should be fine for boats to about 35 foot or so, depemding on how exposed you really are. If the later, larger boats will be fine. Don't bother trying to do anything with rust on the mushroom shaft. It won't do anything.

Both. May bene with his 51' would come by sometime for a weekend.
The biggest I would get full time would be about 28'.
It is about as exposed as you can get, just along the side of the sound with the whole 14 nm of fetch all the way to Long Island.

I was thinking of 7/8" pennants about 15'.

[davidpm]

I was thinking of getting this part.
http://www.defender.com/product.jsp?path=-1|10391|638271|321915|321917&id=91628

For the Surmoor T3c buoy the top chain goes through a hole in the buoy is is secured by a shackle to the pennants at the top of the buoy. It is not the type where the pennants are secured to the bottom of the buoy.

It looks like the shackle will tear up the top of the buoy without this collar.

[JimsCAL]

I'm not a fan of attaching the pennants to the top of the ball. 7/8 pennants should be fine. I use 1 inch on a 33-footer weighing 11,000 lbs. Not quite as exposed as you, but close. The big problem is the fall storms that blow from the NW for a couple of days. Can chafe through a light pennant in no time.

[sailingdog]

I would certainly look at cleaning off the rust and getting down to good metal and re-galvanizing all the gear, if it is in good enough shape. That would give it some protection against future corrosion. Rust is not a protective corrosion layer, unlike the corrosion that forms on Aluminum or some other metals. Removing it and protecting the good metal underneath is really the way to go.

BTW, you say you have 12' of water..is that at low tide, high tide or mid-tide? If that is at low tide, then the 20' of 1/2" chain is probably a bit short, since you're likely close to 1:1 scope on the upper chain at high tide.

[JimsCAL]

Originally Posted by sailingdog

I would certainly look at cleaning off the rust and getting down to good metal and re-galvanizing all the gear, if it is in good enough shape. That would give it some protection against future corrosion. Rust is not a protective corrosion layer, unlike the corrosion that forms on Aluminum or some other metals. Removing it and protecting the good metal underneath is really the way to go.

BTW, you say you have 12' of water..is that at low tide, high tide or mid-tide? If that is at low tide, then the 20' of 1/2" chain is probably a bit short, since you're likely close to 1:1 scope on the upper chain at high tide.

Never seen a galvanized mushroom. New ones come painted, but it doesn't last. Purely to make them look good before they get wet.

Typical guildelines I've seen call for 1.5 times the depth at high tide for the lower chain and 1 times for the upper. Lengths given meet that. Different areas and harbors may have different requirements of course, but it sounds like this won't be put in a regulated mooring field. Can't argue over more scope of course, but this seem fine to me.