Finally The 10000th Post from Wheels!!

[wheels 543]

Well actually, 10001, because not thinking, I made a post congratulating Squid on his new Pride and Joy.

 

There are so many Threads I have been wanting to comment on, I figured I better get this done. Seeing as bbay gave the only suggestions and seeing as I have already spouted on about FC virtues (besides, any more talk on FC and everyone will want an FC boat) I figured Anchor Chain could indeed be a good topic. So.....here we go. Now KM will know if I have been paying attention in class or sleeping in the back row.

 

You would be surprised at the number of people that think Chain is Chain. It's Steel, it's Galved, so what's the problem. Well actually, it is quite a complex subject. Oh boy is it complex. I figured there is no point in getting into all the nerdy technical stuff about chain, like the measurements and MPa figures and so on. They really are meaningless to the normal boatie. That is what your resident Chain supplying expert should be able to advise you on and suggest what you need. Any good chain distributor should be able to take care of all the complex issues without you even knowing there were any to begin with. Sadly, this is becoming a rare situation and many sellers of chain simply take your money and load their one type of chain in your Car boot and send you on your merry way. Unfortunately we are seeing more and more turn up on our door step not so merry, with tales of woe at how they bought such and such Chain and it either just doesn't work on their Gypsy, has wrecked their gypsy, or the most common we are seeing at the moment, the Galv has gone in about 18months and by two years it is a pile of Rust.

 

Now, we are talking Anchor chain here. This will mean a Short Link type chain for starters. A Chain is made to a standard. Hopefully. The problem is, none of the Chinese Chains being brought into the country, meet the recognised standards. Even though many retailers say it is, and we have even seen some that have a piece of paper stating such, but it is nothing more than a piece of paper someone has printed some numbers on. The whole point of a “Standard”, is to ensure the chain meets certain specific tolerances and performance. More on that in a mo.

 

So did you know that each and every manufacturer of anchor winches have their own Chain Gypsy design. As in, it will suit one specific chain standard only and there are dozens of chain standards. One size of chain does not fit all. The real biggy, is that some chains will look like they fit, but actually will only result in your Gypsy being chewed out. So just because your winch model says 8mm for instance, does not mean any ole 8mm chain will fit correctly, or at all. There are a multitude of 8mm Shortlink Galvanised Chains (Same goes for all sizes of course). DIN (stands for "Deutsches Institut für Normung", meaning "German institute for standardisation". EN (stands for European committee of Standardisation) GL (Germanischer Lloyd) not to be confused with Grade L, which is yet another and refers to a low tensile low Carbon Chain, such as PWB-L for instance. L is also the same as G30 (sometimes can be simply G3, but same thing. The G stands for Grade). Then you get into the high tensile chains G40(G4) right up to a G70. Anchor chain does not usually go above 70 and we won't be talking about Ships Chains (called Stud Link) here, as they start at 20mm and go up to humongous.

 

To know what the correct type of chain for your gypsy actually should be, there is a number stamped on the inside of the Gypsy. The number itself will not usually allude to anything, its just be a number or even just some letters which is actually a code. A chain Supplier should be able to look up what the stamping means and say, oh so you need an 8mm DIN 766 chain for example.

So what do all these Standards mean. Well...the idea is so that you as a chain purchaser, gets a chain that meets a minimum set of performance standards. Just like a Motor oil for example. There are dozens of bottles with SAE30W/40 printed on the front, but on the back is some info on what minimum standards the oil meets. It also ensures the chain fits the Gypsy as the manufacturer of the Gypsy intended. What we have been finding of late though, is that even though many Chains say they are of a certain Standard, the performance has been far from such. And Yes, it's Chinese Chain and I hate harping on about Chinese Chain. But it is costing many boaters a lot of money and we have been so busy supplying those poor boaties with proper chain, it has actually been embarrassing as we have struggled to keep up with the demand. So why is Chinese chain a problem? Well firstly, it doesn’t actually have to be. We do have some Chinese products. But we ask for those products to be made to a standard and the Chinese manufacturer complies and does indeed maintain that standard. I know because I regularly test the products to ensure they are. So as I have said many times before, it is not always that a product is Chinese, it is because the specific Importer is asking it to be made cheap so that he can sell it cheap. Well…. supposedly sell it cheap. In many cases, it is so that company can just make a bucket load of money.

Righty then. The Standard, if adhered to, should ensure that a chain that is going to be stated as an AA123, has to have a certain link length, link pitch., that it shall be a certain shape, That it shall have X amount of twist or rotation per so many meters. That it will have a breaking load of X and that it will have a safe working load at a percentage of that X and one real important point here, that it will not deform more than a specific percentage at a specific load. We have had people that have anchored, gone through a bit of a blow, then tried to wind in the chain, only to have it not want to go around the Gypsy anymore. We have a Test Bed that has two big Hydraulic Rams 3m long. I can apply a total of 12tonne to our test specimin, so we can test some fairly decent chain. I have often found issues with the Chinese chains either deforming very early on and/or breaking links at very random loads. Most certainly not coming anywhere near the Standard that the Chain is being Sold as supposedly meeting. Just why this is the case is many and varied, but in a nutshell, it is cutting corners to keep cost down, plus one real important biggy, making high quality Chain is not simply engineering, it is an Art. The very good chain manufacturers are Companies that have done the job for a long long time. And this is one reason why we use an Italian chain called Maggi. Although Maggi have plants in several countries, they are one of those true Italian Chain making “Families“. They have people that have handed down the secrets from Generation to Generation. It is a true art to know how to set the machines up and have them run tickityboo. It is an Art to know how to make high quality steels. It's an art to know how to soften, work and harden Steels just right. And it's an Art to know how to Galvanize well.

 

A big component left out of the Chinese Chain making is the hardening part. This is a very power hungry and thus expensive component of chain making. In fact, it is about 30% of the overall cost and that is why Chinese Chain is about 30% cheaper than the real good ones. Sorry?..what's that I hear you say?? It isn't 30% cheaper????? Funny that eh. In fact, some of the Chinese Chains are being retailed in NZ more expensive than our Italian Chain. Yet we know that the importers are getting it at the much lower price. How do we know? Because China sells to anyone, so the prices are there for anyone that asks. Another important ingredient in the mix of making a good chain, is the Calibration and Normalisation. Normal who? I hear you ask. The Chain making machine is a complex and powerful and incredibly noisy machine. It starts off with a Rod in the diameter the chain is to be. The machine stamps into shape, cuts and welds the link all in one blindingly fast thump. Then a set of knuckles smacks the weld and cuts off any excess to the weld, to ensure it maintains it’s diameter. Then at every 11 links, a set of hydraulic fingers grabs those eleven links and stretches it to a specific length to conform to the specification. Then the chain runs up through a box that has some huge power cables running into it. This Box is an induction coil that instantly heats the Chain to a certain temperature and then the Chain is cooled in either water or Oil (depends on the type of steel being used) to harden it. This part is so power hungry, the Factories are often set up close to the Power station to ensure hey have enough Current.

 

The Galvanising is pretty much as important as the correct size of Chain. Most of us don't like the idea of rusty chain dirtying up our decks and anchor lockers. So we buy a Chain that has been Galvanized, (or some with big pockets may go for the Shiny Bling called Stainless Steel. I won‘t go into SST chain.

So what exactly is Galv. Well actually, the term Galv came from an Italian guy called Galvani, who came up with the process of Galvanizing. Galv is nothing more than Zinc. The exact same Zinc as is that weighty block of shiny stuff you bolt on to your underwater Hull each year only to find it has disappeared again the following year. And that in a nutshell is exactly how your chain is protected. The Galv on your expensive chain is actually sacrificial. It is slowly eroding away. The Zinc coating works in a multiple way. Firstly it prevents corrosion of the Sub metal by forming a physical barrier. Secondly, acting as a sacrificial anode even if this barrier is damaged. When exposed to the atmosphere, zinc reacts with oxygen to form zinc oxide. Moisture in the air causes it to form zinc hydroxide. You may notice a brand new Galv chain after it has been wet for the first time, then produces a white powder on it's surface. That's Zinc oxide and hydroxide. Zinc hydroxide reacts with carbon dioxide to form a thin, impermeable, tenacious and quite insoluble dull gray layer of zinc carbonate. Zinc Carbonate pretty much becomes a barrier which stops further oxidation. So the darker that grey becomes, the more corrosion proof the chain is. Zinc also does two other things to protect the Steel it coats. If by some chance the coating gets badly scratched on say a Rock, the Zinc will continue to protect the bare steel via Galvanic protection. Plus a real neat thing with Zinc is that it is "self healing" to a point. It will migrate back over the Bare steel and continue to protect it. Now don’t go getting fooled by how pretty the Galv looks on the chain. In fact, a good heavy coating of hot dipped Galv can sometimes look pretty ruff. Be very wary of any Chain that has a lovely smooth appearance. There are two or three ways they achieve this. One is by electroplating the Zinc on. It is a cheap easy method, but you can not get a good heavy layer of Zinc this way. Another is to add stuff to the Zinc. The most common is Aluminium, but Calcium can also be added. These are ways to make the Zinc cheaper and go further. But they also result in the Galv not adhering very well. The result is a very rusty piece of Chain in about 18months or less.

 

There are about as many opinions to anchoring as there are makes of Anchors and there are certainly a lot of Anchor designs on the market. Anchor manufacturers are an “interesting” bunch. Of course, each believe their Anchor design is the best and no other comes near. Depending on how you want to read the figures or how the "anchor manufacturer" wants to present them, the fact is, most anchors are very similar in performance. Please note I said most, not all. But how often have we heard people make comments that their old CQR has performed flawlessly for them for years. Yes, some of the new generation anchors set faster or in a smaller distance of pull in other words and some are good at lifting and resetting quickly again if the wind should turn. But we tend to sell an anchor based on what is best for fitting the bow of your boat, what type of boating you do and where you tend to do it most.

But what many (including anchor manufacturers) seem not to understand, is that the Chain is probably the most important component of your anchor system. In fact the chain, in many ways, could be considered more important than the anchor. The top Anchor manufacturers put their Anchor designs through some very rigorous load testing. The Anchors can withstand some massive loads before they fail. Yet so often we see people give little thought and even a lot less money, trying to buy that important link between their precious Boat and expensive anchor tying them to the Seafloor. In my view, Chain is the most important piece in the Anchoring system Jigsaw. Even more important than the anchor. In fact, if you had enough chain, you wouldn’t actually need an anchor at all. The Chain is doing several things, which all combine to make your Boat secure and so that you wake up in the same Bay as you went to sleep in. So firstly it needs to be able to withstand the loads your boat can place on the anchor system and still remain intact and still remain in the correct shape so as you can retrieve it again. So the strength is important. It can sometimes be helpful to go up a couple of grades in strength so as the size can be smaller and thus the length carried in the locker could be more, or you could save weight in the bow if you need. But in my opinion, you go for the heaviest chain in the longest length you can afford to get away with.

 

So how much chain do you need? Well the more the better, but of course, weight and locker size are always the limiting factors. How much chain you need to deploy varies. A rule of thumb is 3 times the depth of the water for all chain and 5 times the depth if you use a Rope Rode. In which case, you need at least a boat length, preferably 1.5 x the length of the boat in Chain. If you have plenty of anchoring room, then just let out as much as you can. There is certainly no harm in more.

Now here is an important Fact. When you double the length of the Chain, you increase the holding ability by 4x.

Contrary to other information you may come across on some websites, the Catenary effect is also very important. Catenary is where the weight of the chain causes it to bend down in an arc. When a Gust of wind hit’s the boat, the boat pulls back on the Chain and will try to lift the Chain off the seabed. This action dissipates a huge amount of energy. The ability to pull the chain straight is quite an effort. If a huge Gust of wind or if you are in a strong blow, you may think your Chain has become straight and tight as an iron rod, but in reality, the ability to actually lift the chain off the bottom all the way to the Anchor is most unlikely. If it did, then the anchor would most likely pull out and you would be off across the bay.

By the way, Catenary comes from the Latin word Catena, which actually means Chain.

Thus Chain is an important element to the setting of the Anchor, due to the Chains weight, which holds the Anchor shank down at the correct attitude and thus allows the Anchor to dig in and set correctly. When you are anchored correctly, the Chain should never be able to lift off the Seabed, ever. If it does, then simply you do not have enough Chain out and you run the risk of the Anchor lifting out.

 

Finally, the last point I want to make is in regards to the Chain at the winch. I see so many people that allow the winch to be the Sampson post. That is very hard on the winch and you could even damage it if in a big blow. It is best to use a “snubber”. Simply a snubber is a line with a chain hook on one end. You hook the chain and the other end you wrap around your Sampson Post or anchoring cleat. You then let the load off the winch and the snubber line takes all the load. As the gust of wind hits, the line stretches and helps to dissipate the energy and the energy it can dissipate can be quite substantial.

Oh and it is extremely important to use the right type of line if you are intending on using one of those fandangled Rope/chain winches. But rope is another long story. And I haven’t even touched on shackles, swivels and Anchor straightners.

 

Well that’s it.

[Guest]

Nice post wheels thanks. You may a saved me a few sleepless nights

 

Now off to buy more chain

[Fusion 0]

10000 well done

[grant 40]

[Guest]

Nice post wheels and great info.

 

But... KM would say that is way to long and did not answer his questions

[Guest]

Nice post wheels and great info.

 

But... KM would say that is way to long and did not answer his questions

 

Troll....

[Guest]

Nice post wheels and great info.

 

But... KM would say that is way to long and did not answer his questions

 

Troll....

 

 

Not! I genuine believe its a Great post. And KM might even have a laugh

[Guest]

Onya Wheels. Just what I needed!

[Guest]

Well done Wheels, Nice one. I always enjoy your posts.

 

Interesting to note you have taken half the time to generate 10,000 posts as it has taken me to clock up 999.

 

[col j 0]

ah no. mr energy is next into hiding

 

by the way. thats way too much information for me to take in.

[OYSTR 1]

Hmmm, I'll be checkin' my chain before the summer season

[Guest Saturday Night Special]

Km Read It Before it was posted

 

Nice post wheels and great info.

 

But... KM would say that is way to long and did not answer his questions

 

Troll....

 

 

Not! I genuine believe its a Great post. And KM might even have a laugh

[John B 106]

I like the way you've linked the whole anchoring security subject together Wheels.

[wheels 543]

For us with out scientific labs, it's is near on impossible to test what is in Zinc. The various metals ion their own is easy, but not once they are alloyed. Zinc will Alloy with dozens of other metals and two are of real concern when Zinc is used for an Anode. Sodium and Magnesium. Magnesium is commonly used in diecast metals. We call it "muckmetal". Sodium is highly reactive, but it is not pure Sodium that is the concern, it is Sodium Chloride, or Salt. So using old anodes picked up off the Boat yards and remelted will lead to a fast erroding Zinc. Now that does not mean it is not doing it's job as an anode, in fact it is operating as an even better anode, it is just that it erodes faster. Pure Magnesium Anodes are used when you are boating mostly in Fresh water.

MB, I would have the shaft electrically tested to ensure you are all OK in the electrical area. You can get a Carbon brush for shafts that simply bond the shaft to the rest of the system and the main Zinc will the take care of the shaft. You can still use a shaft anode and the shaft anode will slow down eroding and once it has gone, the main zinc will then take over protecting.

[Guest]

You are meant to hammer the two halves together. I put a hammer behind and belt it with another hammer and then really heave on the bolts and use threadlock. Its possibly the reason for the early departure, no way to be sure though.

[rigger 47]

Pure Magnesium Anodes are used when you are boating mostly in Fresh water.

 

I thought Magnesium anodes (or an alloy of) were also used on Aluminium hulls

[smithy09 50]

Nice 10,000th Wheels!!

[wheels 543]

Strange. Sorry rigger, I thought I replied yesterday. I know I wrote the post. I can't have pushed submit. Anyway, yes you are correct that Magnesium is also used on Ally boats.