Moorings - Building your own

Any topics on dinghies/tenders. Also the building of moorings, related topics, even free moorings.
mySerenity
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Moorings - Building your own

Post by mySerenity »

For those on the earlier version of the Forum, sorry. But I thought I'd raise this one again as it attracted a lot of interest and feedback last time.



I am yet to lay my mooring and are looking for guidance in the size/shape/make-up of a potential mooring base. Given that our Cat may bottom at very low tide, the possibility of damage from the mooring base structure is a strong possibility. So how do we get around this?



Our thoughts have included the use of a large old tractor tyre, framed with some 20mm steel through the centre and filled with concrete sounded simple enough. The tie down eye could be made flush with the top of the tyre and bent out of stainless steel. If this was done in a sturdy box trailer on a sheet of thick plastic, it could all be towed to fill up with concrete, then when dried, towed to location. I am sure there would be a way to calculate the weight of this, we were planning on 1 tonne.



How we would deliver this into position would be interesting.



Anyone have better ideas?
James
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Jim
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Moorings - Building your own

Post by Jim »

There is a guy with a mooring in the Cairns inlet that consists of an old railway loco wheel. His chain is attatched to the centre so it went down flat, and in a mud bottom like Cairns it would settle well into the bottom grunge no doubt. Saves all the mucking around with concrete.
44c
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Moorings - Building your own

Post by 44c »

I knew a guy who used to lay moorings proffessionally a long time ago, and that's what he used to use - train wheels.
mySerenity
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Moorings - Building your own

Post by mySerenity »

Sounds like the way to go. Anyone works in the railways by any chance? Just thought I'd ask...you never know.



Jim any idea what these things weight?...serious question, I'd have no idea.
James
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Jim
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Moorings - Building your own

Post by Jim »

Hi James, I am not sure how to contact the guy in question about the rolling stock wheel any more. Just looking at a rail wheel I would say that with two guys lifting it would definitely make the veins in your forhead stick out with the effort.

Also while on the subject of moorings, I have been advised by two seasoned boaties not to use chain on the mooring. The theory being the rust factor and the binding up of the links, also in the Cairns inlet the mud is very acidic. They said to use very large diameter nylon rope as it doesn't rust and with a good stainless swivel on the bottom is less likely to bind up by twisting. On the few National Park moorings I have used on some of the local islands this seems to be how they do it, however I have not dived on the moorings, so I am not sure what is down the bottom of the rope. The rope they use on those public moorings is approx. 80mm dia.

Regards,

Jim. Easy 37 #22.
mySerenity
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Moorings - Building your own

Post by mySerenity »

:idea: Have a resolve on the mooring issue (finally). :lol: :lol:

We have welded a stainless steel ‘screw’, which we intend screwing into the ground and with heavy chain, securing the buoy too. The screw is 2m long (30mm thick) with a 5mm plate (300mm diameter) at the base and an eye at the top, and that’s it, that simple. Commonly called the Helix Anchor.



We tested the mooring ‘mud’ prior to cutting the length and found solid ground around 1.75m, so the unit should hold well. At around AUD $85 for all the second hand Stainless Steel, it sounds too simple to be true. For the skeptical ones, we got most of our data from ‘Hurricane’ websites in the US and searches for Helix anchors.


Advantages of the Helix
Comparing the holding power of a helix anchor to a traditional mushroom or dead weight anchor is like comparing a wood screw to a thumbtack or paperweight. A study by the BoatU.S. Foundation, Cruising World magazine, and Massachusetts Institute of Technology (MIT) found that a 500 lb. buried mushroom could be pulled out with 1,200 pounds of pull (supplied by a 900 h.p. tug); an 8,000 pound dead weight (concrete) anchor could be pulled out with 4,000 pounds of pull. The helix, however, could not be pulled out by the tug and the strain gauge recorded 12,000 pounds of pull—its maximum—before a shackle was burst apart by the strain. Scope in each case was slightly less than 3:1. (In an earlier test, a strain gauge had registered 20,800 pounds before the hawser snapped.)
Courtesy: http://www.boatus.com/hurricanes/moorings.asp


We are only trying to achieve a maximum of a 1/4 this 20,000 pound pull strength due to the conditions expected in this mooring position (and that we don’t get hurricanes here either). I will update the Puremajek site at some stage before July 2007 with dimensions and pictures once installed.



Thank you for all the input from everyone
James
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https://www.youtube.com/user/puremajek
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Bruce
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Moorings - Building your own

Post by Bruce »

Old railway wheels are the go, with a good swivel attached. A length of heavy chain is then attached about 1/3rd the total length required. Heavy mooring rope is then attached to the chain via another swivel, making up the other 2/3rds required for total length of the mooring.

This is a "general" setup that is commonly used here in Tassie. The chain does not rust out as it is below the waterline & therefore is deprived of the oxygen needed to form rust. The chain is used as a "damper" in rough weather so that the vessel does not jerk directly at full force on the railway wheel.

To place the mooring, many people place the railway wheel in an inflated tractor tyre tube on the beach at low tide. When the tide comes in, the tube floats and can then be easily towed/rowed out to the mooring site where it is punctured and sunk into position.
jason

Moorings - Building your own

Post by jason »

Hi all,



If you go to this link - http://www.cruisersforum.com/forums/f48 ... 689-4.html you'll see a couple jpegs and description of what we use to make a mooring with extra anchors.



If we're in one area long enough we do make a mooring like this...just using 30' of chain from each anchor (2-3 anchors) through the big shackle underwater to a swivel which then has a good sized line going up to the floats/bridle. We then just sail on and off it at will and don't have to hassle with anchoring....especially when the anchorage is tight for what-ever reason. Also great for confidence if in storm areas...no last minute panic to get set-up.



No good if you'll dry out as you'll surely bump the anchors unless you're there to push the boat around.



Simply keep an eye out for over-sized cheap anchors.....you can dive on them to make sure they're set good, but just taking care using the anchoring technique works th emajority of the time. I think we had 300aud into our set-up - one 45 lb plough, one 35lb plough used 10mm chain (all like new and bought cheap) and one 70 lb SS hvy danforth type anchor I found lost in the mud. Portable...take it with you!



best - Jay
mySerenity
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Moorings - Building your own

Post by mySerenity »

Jason



Thank you for your input, great reading too. I have found some more information here:

http://www.anchor-marine.com.au/anchor&.htm
James
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https://www.diycatamaran.com

https://www.youtube.com/user/puremajek
_____________________________________________
Crasara Cruzin

Moorings - Building your own

Post by Crasara Cruzin »

Hi Guys,

We made our mooring for Victoria Point.

Local Bloke wanted $1500 for materials plus $100p/h for him and barge.



Used 3xtruck tyres filled with concrete, 150mm PVC Ppe in the centre virtically with 1" Hot Gal reo layed horizontally through centre covered it with plastic pipe laid them about 1m apart linked wheels with double 1/2" chain (because I had some), then laid 6m of 6" Chain ($125) then 6m of 1" mooring rope. total cost less than $300 we also attached 2 large annodes to the chains. It is now (2 years after) imbeded level with the sea floor and should hold the Titanic. Floated out individully on 4 44Gal Drums

Railway wheels wern't available ($200 each from Scrapmetal place Hemmant) all being exported to China.

:wink:
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