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D.I.Y. Moorings - Unitized System.

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Created by cisco > 9 months ago, 27 Sep 2014
cisco
QLD, 12323 posts
27 Sep 2014 2:05AM
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Moorings are an item that concern many of us here.

I have a fore and aft mooring licence in the "Distillery Reach" of the Burnett River, to which I have to add blocks and tackle for it to be of any use to me.

Being a frugal person as most small boat sailors are and a D.I.Y-er as many are too, I have attacked the problem of getting the blocks in place for the lowest cost.

Different mooring locations require different tackle and tackle is fairly much a fixed cost. The blocks however are where you can reduce the usual costs.

Managing the weight was my main concern at the outset and where the cost savings mostly are. We all know we can get a one tonne concrete block with a loop of rio steel in it for $100 or $200 from the local concrete batching plant.

Getting it from there to where you want it is the costly part and then you only get half the value of it because concrete only wieghs half of what it does on land when it is submerged in water.

Steel on the other hand is denser and gives 90% weight when submerged and tonnes of it gets thrown out everyday.

I found a bunch of these which are cast steel cogs weighing 30 kg. A round steel plate would do.




Semi trailer brake drums are mostly standard size. This one weighs 50 kg with the fabricated bar welded in. Cast steel needs to be used because old cast iron will crack when welded. I have used low hydrogen welding rods.




The clutch plate, brake discs bolt and bar have added another 38 kg.


It is then bolted and welded together with a resultant weight of 118 kg. The eye is for lifting and lowering purposes. The mooring line is looped around the captured bar on the rounded area. It can be filled with concrete or be left open to fill with mud.


This block can be rafted to the sinking location using two 220 litre drums strapped to three timber beams. The raft should also handle a double of these barred together, having approx 400 kg buoyancy.

I think the material cost of this block has come in well under $100.

I am having this as my downstream tidal block and two of them bar welded together as my upstream river current block.

For a swing mooring, three of these could be laid in a triangle and tackled together.

I feel confident that my set up will be quite adequate for my 4 tonne yacht.


Ramona
NSW, 7555 posts
27 Sep 2014 8:30AM
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So this is going onto a mud bottom? Are you using rope direct to the rounded bar or chain?

cisco
QLD, 12323 posts
27 Sep 2014 2:41PM
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The mooring location is a bit difficult. There is a narrow ledge from the shore line which deepens to about 4 or 5 metres and then drops off to the gouged out river bed depth of around 12 to 15 metres.

I heard a story of one guy who was laying a one metre square by 300 mm thick concrete slab that slid off the shelf. The large surface area of it looks to have been the cause.

The bottom of the shelf is mud sand and silt but is still fresh from the floods so maybe not a great deal of mud there yet.

I am building two moorings for a mate and myself adjoining. We will lay the two single block downstream moorings first in 2.5 metres of water at lowest astronomical tide, let them settle for a bit and then moor one of our yachts between them to test holding.

We are using 20 mm Super Dan line which will have a spliced loop with irrigation hose anti chafe on it. This will be passed under the bar and the other end of the line drawn through it and cinched up hard.

The river flow and the various chemicals in it causes electrolysis in chain giving it only about a three year life span. The former commercial mooring operator changed from chain to all rope tackle way back.

A side benefit of this system is that to replace the tackle, all a diver needs is a knife and the new tackle.

We both have 10 metre fin keel yachts (Lotus 9.2 and Adams 31) with around 4 tonnes displacement. The strategy of course is at the first sign of flooding, we get our boats out of there and down towards the river mouth.

Your critical assessment of what I am doing is welcome. Objectivity is a great thing.

brizzydave
406 posts
27 Sep 2014 1:06PM
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I thought they had to be eg. 400 kilos say, for a 30 foot boat. We had one put down a month ago, the concrete block variety. It was a vacant one moved and set up by the local mooring bloke. Or can they be less if there's both fore/aft?

You fitting a swivel?

SandS
VIC, 5904 posts
27 Sep 2014 10:46PM
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would it be worth welding or bolting some rods down off the bottom ,to grab the river bed ??? may help stop it sliding ??

brizzydave
406 posts
27 Sep 2014 9:45PM
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It's a good idea what you are doing. Being an ex - boilermaker myself (shipyards) I love anything steel.

cisco
QLD, 12323 posts
28 Sep 2014 1:19AM
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brizzydave said..
I thought they had to be eg. 400 kilos say, for a 30 foot boat. We had one put down a month ago, the concrete block variety. It was a vacant one moved and set up by the local mooring bloke. Or can they be less if there's both fore/aft?

You fitting a swivel?



A fore and aft mooring needs to have sufficient holding power for the predominant flow of water. If it is located in a tidal river (as mine is) it is logical to assume that the vessel will be moored with it's head upstream and that the upstream mooring needs to be sufficiently capable of holding the vessel in place when the river flow is say up to 10% higher than normal and during a spring tide ebb.

That could be a current flow past the boat of 6 knots or more if the river starts to flood.

The minimum weight of the mooring block is determined by the load (current flow ) and the scope of the mooring line. What the formula is I don't know but one can refer to the anchoring table posted above.

A rule of thumb for anchoring might be "A pound of anchor and a yard of chain per foot of boat length." My boat is currently anchored in 2 metres of water on a 30 pound (13 kg) anchor with 20 metres of chain out and has not yet moved in 35 knot gusts and that is in sloppy mud.

With my river mooring I will have a 250 kg (550 pound) anchor/block with a 30 foot line in 6 foot of water which is a 5:1 scope. I believe it is going to hold. The stern block is only to hold it from swinging during the flood tide.

I have thought of having spike rods on the underside of the block to secure it in the river bottom.

P.S. Being a fore and aft mooring there is no need for a swivel.

brizzydave
406 posts
28 Sep 2014 7:17AM
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Ah..I see. Interesting!
I'm paranoid about swivels because pro crab pots fouled a mooring I was on and a spliced eye undid itself and my boat floated away and beached itself. Grrrr.

Ramona
NSW, 7555 posts
28 Sep 2014 9:36AM
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Fore and aft mooring probably does not need a swivel.

My mooring weight is a single tram wheel with about 10 feet of large chain, swivel then rope riser. It was laid for a 38 foot motorsailer. My old mooring which I still have is also a tram wheel with less chain and was laid to suit my 30 footer of 4 tons. Swing moorings in a very strong tidal river. I actually have a drum raft on my old mooring at the moment which I intend to move to a position 20 feet or so West of my new mooring and link the two tram wheels together. Not because I need the extra weight but simply because I have to remove the old machinery. If someone wants to buy the mooring it will save me some effort!

I intend to link the two weights together with old terylene anchor rope from my fishing vessel. It sinks and will bury in the sand. I think a lot of the holding power is not so much the weight but the shape. Something thats flattish with preferably a bit of a hollow bottom that can suck on the bottom in mud or sand. The bottom under my boat is very hard clear sand, the wheels don't get covered by much sand.

With the fairly shallow depth you can have regular dives to inspect and keep a regular check for wear. With hookah gear I spend a bit of time sitting on the bottom checking mine out. I think a long eye splice in 24 mm nylon rope would make a good riser. I would not bother with anti chafe but change the rope more regularly. Long eye splice would be easy to replace and you would have double the rope over the wear part.

Ramona
NSW, 7555 posts
28 Sep 2014 9:42AM
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Just in case there is some confusion. I don't mean splice the rope underwater but make the long eye splice beforehand and pass the end of the eye through the attachment point. Then pass the tail through the loop and pull down.

cisco
QLD, 12323 posts
28 Sep 2014 11:14AM
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Ramona said..
Just in case there is some confusion. I don't mean splice the rope underwater but make the long eye splice beforehand and pass the end of the eye through the attachment point. Then pass the tail through the loop and pull down.


That is how I will be attaching the tackle.

Your "tram" wheels. What diameter and weight are they and are they solid or spoked??

Ramona
NSW, 7555 posts
28 Sep 2014 6:50PM
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As far as I can tell they are like these.

nla.gov.au/nla.obj-141665891/view

No idea how heavy, the contractor laid them. The bottom chain just passes though a hole then is shackled back on it's self.

Fiesta
QLD, 122 posts
28 Sep 2014 8:07PM
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Does the rust of the mild steel bits cause problems with chafing on the rope that you are going to loop around the bars?

Good detail on the pics BTW

cisco
QLD, 12323 posts
28 Sep 2014 11:03PM
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Fiesta said..
Does the rust of the mild steel bits cause problems with chafing on the rope that you are going to loop around the bars?

Good detail on the pics BTW


Everyone says steel does not rust when oxygen is eliminated ie from being underwater. I think electrolysis ie galvanic action due to dissimilar metals being in a common medium will be of more concern than rust.

The brake drums, cog wheels and brake discs are fairly low grade cast steel ie low carbon content and the welded in bars and threaded rod are mild steel with a bit higher carbon content. I don't think there is that much difference of the metals to be a great concern.

There has been a fair bit of labour involved but the dollar cost is low so I will throw my hat in the ring and see what transpires. The bars are 2 inches thick and because it is not a swing mooring I think chafe will be minimal.

I will keep you all up to date as the project moves forward.

cisco
QLD, 12323 posts
29 Sep 2014 12:11PM
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Ramona said..
I actually have a drum raft on my old mooring at the moment which I intend to move to a position 20 feet or so West of my new mooring and link the two tram wheels together. Not because I need the extra weight but simply because I have to remove the old machinery. If someone wants to buy the mooring it will save me some effort!


Ramona, could you possibly post a photo or two of your drum raft. I am due to build one soon and am looking for ideas.

Ramona
NSW, 7555 posts
29 Sep 2014 6:40PM
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cisco said..

Ramona said..
I actually have a drum raft on my old mooring at the moment which I intend to move to a position 20 feet or so West of my new mooring and link the two tram wheels together. Not because I need the extra weight but simply because I have to remove the old machinery. If someone wants to buy the mooring it will save me some effort!



Ramona, could you possibly post a photo or two of your drum raft. I am due to build one soon and am looking for ideas.


Going fishing in the morning, will try and remember to take the camera.

cisco
QLD, 12323 posts
30 Sep 2014 12:18AM
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Thank you muchly.

Ramona
NSW, 7555 posts
30 Sep 2014 9:37AM
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Caught one undersize flathead this morning but beautiful day out. The raft is part of someones floating oyster farm I rescued. I intend to put a hardwood beam across the centre to centralise the lift when I feel like doing something with this project.
If I was to build one, I would use steel 44's and weld angle iron across the ends and a central beam to support the weight.

[URL=.html] [/URL]

Hinton Bay
TAS, 7 posts
30 Sep 2014 11:11AM
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Fiesta said..
Does the rust of the mild steel bits cause problems with chafing on the rope that you are going to loop around the bars?

Good detail on the pics BTW


Hi Everyone,
I have a swing mooring that is made up from a machine gear I brought from the scrap steel yard and weighs in around 600kg, it is chained through the gear (no welding) to 3 meters of heavy D link chain and another 6 meters of lighter chain then finished with a 3 meter nylon riser. There is one swivel between the chain which is replaced every 24 months during inspection, with this set up the yacht only ever rides on the chain which works as a spring.

Being of a frugal nature I sourced all the gear myself and just paid the local mooring guys to put it together and drop it in for me which saved me heaps.

It has been in 5 years now and there are no rusting issues and as long as I keep the services up all is good with Club Marine.

Cheers Rod


cisco
QLD, 12323 posts
30 Sep 2014 1:19PM
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Ramona said..
Caught one undersize flathead this morning but beautiful day out. The raft is part of someones floating oyster farm I rescued. I intend to put a hardwood beam across the centre to centralise the lift when I feel like doing something with this project.
If I was to build one, I would use steel 44's and weld angle iron across the ends and a central beam to support the weight.

[URL= .html]


Thanks Ramona. That one is a bit heavy duty for what I need but you are lucky to have scored it.

What you described is about what I had in mind.

I am looking at two steel drums with two hard wood beams, steel straps around the drums with threaded rod welded to each end of the straps and bolted through the beams. A piece of form ply each side batten screwed to the beams to create a working deck with cleats etc and a central beam to carry the load.

This can be disassembled to replace drums if they rust out and can be stored behind the shed when not in use.

I will post pics when I build it.

Wander66
QLD, 294 posts
22 Aug 2015 12:29PM
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Thought I would resurrect this thread with some pics of the latest version of a steel mooring block for my 33 ft Carter on the Burnett River. This one has been made from cast steel weights that I found at the local scrap merchant, originally from the railways, possibly used to maintain tension on the overhead powerlines. They come in three different weights 30 kg, 38 kg and 40 kg.



The design and dimensions are shown below but the basis is to use 3 of the 40 kg weights as footings that will sink into and hold into the mud and 380 kg of weights bolted and welded together as a log that will lay perpendicular to the flow with a bar to attach the mooring rope to. Total weight is around 520 kg so it should have the advantage of providing ballast as well as having good grip in soft mud. The aft mooring block will be of similar design but with less weights maybe around 300 kg. The front view photo shows the completed fore mooring block and the side view is before I welded in the top rod and tacked the nut and washer on. Please excuse my creative welding not pretty but it will hold.

The design has had substantial input and support from the Cisco Kid and we have caught up several times over the past month, yes he is just as helpful and considerate in person as he is online and may even bear a slight resemblance to his namesake depending on which actor you referring to. He has offered the use of his raft to deliver the blocks to my mooring lease, obviously we will have to beef it up for the extra weight. Should be interesting!












cisco
QLD, 12323 posts
24 Aug 2015 12:05AM
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Much thanks to Wanderer66 (so he was born in 1966, we will hack his bank account soon ) for finding and reviving this thread. It goes back aways.

W66 made a really good score when he found these weights at one of the local scrap yards because they are weights as opposed to just being heavy steel, ie they are as dense scrap steel as you can get.

The benefit of using steel (cast) as opposed to concrete is that you achieve 90% of the weight benefit once immersed whereas with concrete you only achieve 50%. The point being if you have to handle 1 tonne of concrete on shore for a half a tonne of benefit in the water, the moving cost ( be it financial or infrastructural ) will be virtually twice that of using cast steel.

So here we have another example of Seabreezers meeting up and doing stuff. Seabreezers that I have met up with personally so far are HaveFun, MorningBird, Lazzerea, Lexmark, Jode5, Manitulak (before the forum), Wanderer66, nswsailor and possibly one or two more that my alcohol addled brain does not remember.

What a great forum this is!!!

Back on topic.

My mooring barge (there is another thread on that) was capable with a 250 kg block but will definitely need beefing up for W66's twice the weight.

We will keep you updated with pics etc. Stay tuned.

P.S. I am just Cisco, not the Cisco Kid. Strewth, I turned 65 on the 15 th of August so I am no longer a "kid". (now you can try hacking my bank account.)

Edit:- That is Gilbert Rowland in my avatar. He like I nearly always have a fag hanging out of our mouth unfortunately.

Ramona
NSW, 7555 posts
24 Aug 2015 7:06PM
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Damn we share the same birthday but I'm 2 years older!

Seems a lot of weight for a 33 footer. I would prefer a weight that is flat and sucks to the bottom. My mooring is a single tram wheel and was initially for a 38 footer. {Strong tidal conditions].

cisco
QLD, 12323 posts
25 Aug 2015 11:44AM
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Well waddya know. Princess Anne has the same birthday and year as me too but I reckon I carry my age a bit better than her.

Many of the mooring blocks put in the Burnett River are 1 metre square by 400 mm thick concrete slabs. Because of their surface area they tend to slide on the mud and some have actualyl slid into the deep of the river.

What we are trying to achieve are blocks that will sink into the mud.

I was thinking that W66's 520 kg was a bit of overkill for a Carter 33 too but his mooring location is around the corner from me in the town reach where the current is probably a bit stronger than my location which may get a bit of back wash.

Better to have too much weight than too little.

So Happy Birthday to you too.

samsturdy
NSW, 1659 posts
25 Aug 2015 3:06PM
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You blokes boasting about your August Birthdays, well I'm a Leo too. August 4th, Queen Mum's Birthday. So glad to see
a few of us so close to Royalty!!!!!!. My mooring is a block but there's little current in McCarrs Creek, just a bit of tidal
influence. Boat always lies side on to the current if there's no wind.


Ramona
NSW, 7555 posts
25 Aug 2015 5:42PM
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Had to rescue a friends gin palace this afternoon after she came off her mooring. Have not found the remnants of the mooring yet but I would say the bottom shackle gave way. We are enjoying a Gale force Southerly here at the moment and about to have a bit of a flood!

nswsailor
NSW, 1431 posts
25 Aug 2015 9:01PM
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G-- Damit, I thought you guys were all older than me, well Sam may have a day on me!

All the above is making me feel old!

The secret with concrete blocks is that they should be sunk into the sand.
My block is similar to those mentioned and it only took me 15 minutes to sink it in by just fanning the sand etc away.

Sent from Cape Gloucester at the Shaggers [SICYC] meeting [400 boats expected!]

Wander66
QLD, 294 posts
25 Aug 2015 9:21PM
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Apologies Señor Cisco for disregarding your maturity, yes I am nearly 50, hopefully that day in July 2016 will be spent with the family somewhere pleasantly warm and the water lapping the hull of Itchy Feet. Wouldn't bother with the bank account thing, any spare cash has gone into a boat sized hole in the water with more to come I'm sure. Agree that this is an excellent forum with a uniquely Australian flavour, I have learnt a lot over the last year. However there is more to the forum than just the information exchange, there is a whole range of entertainment for example: the sailing adventures of Samsturdy, love found and lost with McNaughtical, drama with the troll wars (not fun by the way) and straight out lust from Cisco for Shaggybaxter's new boat! I look forward to meeting with many of you as I find the time and confidence to venture further afield on the water.

Ramona I agree that the mooring weight is greater than strictly necessary but I prefer to sleep well at night and although nothing will hold a boat when the water is 7.34 m above HAT (as in the 2013 floods), the Burnett Catchment is about 33,000 square kilometres in area and we do experience at least one minor flood per year so it pays to be prepared. Plus I bought 1.3 tonnes of those weights so I might as well use them, should have rung Ford to see if they need another ad for the Ranger it carried them quite well.

McNaughtical
NSW, 908 posts
25 Aug 2015 9:59PM
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Wander66 said..
Apologies Señor Cisco for disregarding your maturity, yes I am nearly 50, hopefully that day in July 2016 will be spent with the family somewhere pleasantly warm and the water lapping the hull of Itchy Feet. Wouldn't bother with the bank account thing, any spare cash has gone into a boat sized hole in the water with more to come I'm sure. Agree that this is an excellent forum with a uniquely Australian flavour, I have learnt a lot over the last year. However there is more to the forum than just the information exchange, there is a whole range of entertainment for example: the sailing adventures of Samsturdy, love found and lost with McNaughtical, drama with the troll wars (not fun by the way) and straight out lust from Cisco for Shaggybaxter's new boat! I look forward to meeting with many of you as I find the time and confidence to venture further afield on the water.

Ramona I agree that the mooring weight is greater than strictly necessary but I prefer to sleep well at night and although nothing will hold a boat when the water is 7.34 m above HAT (as in the 2013 floods), the Burnett Catchment is about 33,000 square kilometres in area and we do experience at least one minor flood per year so it pays to be prepared. Plus I bought 1.3 tonnes of those weights so I might as well use them, should have rung Ford to see if they need another ad for the Ranger it carried them quite well.


Wander, yes, it is a great forum, a lot of decent people on here, I have met up with a couple so far, and have had some good help over the distance from HG.

I am one of the couple that Cisco can't remember meeting due to alcohol addled brain....lol...

I was very impressed with your mooring which was under construction when my son and I called in on you and your lovely wife Cisco.

I met NSW when he came past my way in his beautifully cared for Top Hat., and I hope to get to the Seabreeze get together in November .... will be very upset to miss it.

Looking forward to meeting many more of you in time.

cisco
QLD, 12323 posts
25 Aug 2015 10:58PM
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nswsailor said..

Sent from Cape Gloucester at the Shaggers [SICYC] meeting [400 boats expected!]



Sounds like you are having a high old time. Wish I could be there.

cisco
QLD, 12323 posts
25 Aug 2015 11:20PM
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Wander66 said..
Apologies Señor Cisco for disregarding your maturity,
Just Cisco will do and apologies are not necessary.

yes I am nearly 50, hopefully that day in July 2016 will be spent with the family somewhere pleasantly warm and the water lapping the hull of Itchy Feet.

That is why we do what we do.

Wouldn't bother with the bank account thing, any spare cash has gone into a boat sized hole in the water with more to come I'm sure. Agree that this is an excellent forum with a uniquely Australian flavour, I have learnt a lot over the last year. However there is more to the forum than just the information exchange, there is a whole range of entertainment for example: the sailing adventures of Samsturdy, love found and lost with McNaughtical, drama with the troll wars (not fun by the way) and straight out lust from Cisco for Shaggybaxter's new boat!

Well she is sleek and trim with broad hips and love handles in the right place. How could one not lust after it??

I look forward to meeting with many of you as I find the time and confidence to venture further afield on the water.

Ramona I agree that the mooring weight is greater than strictly necessary but I prefer to sleep well at night and although nothing will hold a boat when the water is 7.34 m above HAT (as in the 2013 floods), the Burnett Catchment is about 33,000 square kilometres in area and we do experience at least one minor flood per year so it pays to be prepared. Plus I bought 1.3 tonnes of those weights so I might as well use them, should have rung Ford to see if they need another ad for the Ranger it carried them quite well.


My mooring crane/truck man has gone cruising for 4 or 5 weeks so we have plenty of time to fine tune your blocks and make up mooring lines. Don't go buying any mooring line as John and I bought a 125 m coil of 20 mm Super Dan (more than twice the strength of Silva line) and will definitely have enough left to do your mooring.



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"D.I.Y. Moorings - Unitized System." started by cisco