Mooring weight / Typhoon

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Jonathan Dodge

Mooring weight / Typhoon

Post by Jonathan Dodge »

I plan on dropping a new mooring soon. I have a 4' metal I beam 150LBS. Inland lake bay, the boat will get most of any storm.
15' water, sand bottom. 15' of chain with mooring line and ball.
???? is 150lbs enough??

Thanks

Jonathan Dodge
"Lion's Whelp"
CD Typhoon
Lindstrom, MN



Jonathan.D.Dodge@HealthPartners.com
Bob Loewenstein

Re: Mooring weight / Typhoon

Post by Bob Loewenstein »

Jonathan Dodge wrote: I plan on dropping a new mooring soon. I have a 4' metal I beam 150LBS. Inland lake bay, the boat will get most of any storm.
15' water, sand bottom. 15' of chain with mooring line and ball.
???? is 150lbs enough??
In my opinion 150lbs is not enough. I live on Lake Geneva in Wisconsin and there are alot of boats on moorings here. My direct experience is with a number of moorings the local camp down the hill provides. All of these anchors vary in weight between 750 and 1750 lbs of concrete. Boats on these moorings vary between day sailers up to a 30' (heavier boats get heavier concrete anchors). We are exposed to the south and west, and get some high winds.

I keep my 27' CD here (7500lb displacement) and use 1750lbs of concrete with a scope of about 2:1 of 3/8" chain to a mooring buoy and mooring lines to the chain. Make sure your mooring lines are long enough and don't exit the bow with too great an angle. Also use chafe guards of some sort on them. My concrete is also on a slight slope and any winds would help dig the anchor in.

A typhoon is about 2000lbs displacement, right? You better add more chain, too. If you're in 15' of water with 15' of chain, a big wave will lift your boat and your boat will lift that 150lb piece of iron right up off the bottom. If you can get away with it, use at least 2:1 scope. The mooring field here is about 1.6:1 only because of the boat density in the field. I'm a bit away from the field and have more room for my 2:1.

Bob



rfl@yerkes.uchicago.edu
Bob Chamberland

Re: Mooring weight / Typhoon

Post by Bob Chamberland »

Hi Jonathon,
Check out Chapman. You need more chain and somewhere in there you need a swivel.Wave action will add to the water depth some. The swivel is needed to prevent your chain from winding itself around your mooring connection or around itself. Chapman recommends two lengths of chain. A heavy chain 1-12 times the water depth connected to the mooring anchor then a swivel then a lighter chain equal to the water depth then your mooring buoy. He recommends that this all be connected to a mushroom anchor (In the WEST catalog they recommend 100#). I would be concerned that your I beam could be dragged along the bottom during a blow since it wont bury itself like a mushroom anchor would.

Bob Chamberland

Jonathan Dodge wrote: I plan on dropping a new mooring soon. I have a 4' metal I beam 150LBS. Inland lake bay, the boat will get most of any storm.
15' water, sand bottom. 15' of chain with mooring line and ball.
???? is 150lbs enough??

Thanks

Jonathan Dodge
"Lion's Whelp"
CD Typhoon
Lindstrom, MN


cha62759@traverse.com
John Vigor

Re: Mooring weight / Typhoon

Post by John Vigor »

Jonathan, the rule of thumb is at least 10 pounds of mushroom anchor for every foot of boat length. For concrete blocks, which lose much of their weight under water, at least three times more weight than mushroom anchors.

John Vigor
CD25D "Jabula"



jvigor@qwest.net
Jonathan

Thanks

Post by Jonathan »

Thanks for all the info. I will get the mooring dropped in this weekend (if I get my sons swing set up).
Fair winds

Jonathan
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