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Discussion Starter #1 (Edited)
My boat is at a friends dock but I can only secure the boat on one side to the dock. I did make a 200 lbs concrete mushroom anchor that I dropped about 30' away from the dock, had 15' of heavy chain and 5' of light chain. The high tide water depth is 4.5'. Well we just had a really strong wind blow in and it dragged the anchor enough for the boat to rub against the dock.

I am wondering if anyone has used a 20' length of galvanized pipe and water jetted it into the bottom about 10' and used it as a mooring pylon?

I was thinking of using 2" diameter pipe, have 10' in the bottom, 4.5' in the water and the rest standing above water line. I was going to make a loop with the heavy chain and drop the loop over the pylon so it reacts with the pylon at the bottom of the pole. Then use the remaining heavy chain to extend over toward the dock, then have my light chain secured to my buoy, then run dock line to the cleats on the boat.

What do you think?

Oh forgot to mention this is a Chrysler 22 at 3000 lbs
 

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What do you think?
I don't think this pipe will last very long in salt/brackish water. And I don't think 2" pipe is strong enough for this job to begin with.
How big is your boat?
 

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I would consider driving a sharpened pressure treated wood post into the bottom as deep as you can at the mooring spot, and then securing your 200 lb mushroom anchor to it to stop it from dragging.
 

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Would fender boards be easier? You'd have protection wherever you went, not at just your friend's dock.
 

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I'm not exactly sure how one goes about making a mushroom anchor out of concrete, but I do know that concrete loses something like 1/3 of it's weight under water. You would be much better served using a proper anchor, especially if the holding is good, to hold your boat off the dock, than concrete or a mushroom anchor.
But all the messing around won't come near the security that a real piling or two, set by a professional, will give you. It will also increase the value of the dock.
 

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islander bahama 24
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I'm not clear on your issue only tied to dock on one side that's how most vessels are tied to the docks in marinas do you use fenders or just let your vessel rub on the dock.
 

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Discussion Starter #10
Thanks for the replies everyone. The problem with the dock is that it is elevated too high, and the deck boards overhang the joists by 6". This means when the wind shifts and pushes the boat into the dock the stanchions will bounce up and down and smash into the deck boards. During the last storm the waves were up to 3' high and the stanchion/lifeline broke about 8 deck boards (thank god they were old and broke away) and the toe rail was beat up and the deck of the boat was all scratched up from the dock joists and boards.

I do like the idea of the mooring whips but i don't know if they would be strong enough. n All of the pictures show them being used in canals. My boat is docked at one of the widest points of the St Johns which is 3+ miles wide so the waves and wind can get pretty bad.

I will research that idea and see if it will be strong enough. Maybe I could modify the design and DIY at the dock?

As for the concrete anchor…
I bent rebar and formed grappling hook shape, then suspended that in an old skimming pool sand filter that i had cut in half a long time ago. That gave me the curved bottom. I then poured in the concrete and formed it to create the mushroom shape so it would dig into the bottom.
 

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200 lb of crete wouldn't hold a dingy .. in water crete is near weightless. We have 1000 lb blocks in the river and they can still move pretty easy.
 

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I agree that 200 pounds is not going to work. How about a helix mooring anchor. That will hold.

Sent from my ADR6425LVW using Tapatalk
 

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The problem with the dock is that it is elevated too high, and the deck boards overhang the joists by 6". This means when the wind shifts and pushes the boat into the dock the stanchions will bounce up and down and smash into the deck boards.
Can you add horizontal wood planks screwed to the posts below the deck level to keep your boat from getting caught by the deck? You can first attach pressure treated 4x4 sections to the posts to make the boards flush with the deck. That would be easier and cheaper than making a proper mooring.
 

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Zac, concrete as mentioned isn't dense enough. In fact it consists to a large extent of water. Dry it out all the way and it crumbles in your hand. And mushroom anchors don't hold until they've been down long enough to set and bury. Given something lightweight light concrete...that could take a while.

A lot of places use old railroad wheels (big steel wheel) as mushrooms, they're dense enough to go down, and sold as scrap metal once the wheel has taken too much damage.

Your best bet might be a couple of helix anchors (ground screws) in the bottom.

This past summer a friend of mine, docked in a lake, asked me "What kind of bozo puts twenty feet of galvanized pipe next to a dock?!" after his boat was IMPALED on it due to drought water levels. That pipe will leave a legacy after the top has rusted away, and you never know who it might catch.

Better to use proper ground tackle of some kind. And work on something, maybe made from old tires, plywood sheet, or large heavy duty floats or mooring balls, on the dock side of the boat, too. The big orange balls can be very effective, as can simple BIG fenders.
 

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islander bahama 24
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OK now I have the info to help I hope. It sounds like a couple of small mooring floats would do the job basicly short sections of floating dock about 3 ft wide and 5 to 10 ft long to go between the pier and the vessel to keep the boat away from the pier and they move with the tide or wind wave actions fwiw
 

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{snip}
I do like the idea of the mooring whips but i don't know if they would be strong enough. n All of the pictures show them being used in canals. My boat is docked at one of the widest points of the St Johns which is 3+ miles wide so the waves and wind can get pretty bad.

I will research that idea and see if it will be strong enough. Maybe I could modify the design and DIY at the dock?
Is your boat bigger than 60'/60,000lbs? If you think the recommended size for your boat may not be enough, do what I do when I buy shoes: get the next larger size (or, in your case, get two sets). :)
 

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Discussion Starter #17
Thanks again for the responses…
After doing some research into the mooring whips, I found something so simple it seems too good to be true. People are using a 2' long piece of PVC pipe with a cap at both ends and running their dock line through the center of the pipe and cleat one end to the boat and the other to the dock. The pipe keeps the boat from coming too close to the dock, and since it is attached with rope at both ends the angle changes with the tides. Here is are some sample photos that shows how it works…
 

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Cool! Mini-mooring whips---and small enough to keep on the boat, so you can use them wherever you go.
 

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Discussion Starter #19
Cool! Mini-mooring whips---and small enough to keep on the boat, so you can use them wherever you go.
Yeah I know… How sweet would this be if they actually work? I will make up a pair and bring them down to the boat on a day with some wave action and see what happens.
 

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Yeah I know… How sweet would this be if they actually work? I will make up a pair and bring them down to the boat on a day with some wave action and see what happens.
Good idea but I would have 2 concerns: 1. chafe of the rope by the edges of the pipe 2. not enough give when you get bigger waves, possibly breaking the pipe or pulling the cleats out. Did you see the substantial fenders mounted on the dock? I would have more faith in something like that.
 
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